Class Book.'Z-i ? Copyright^ . COPYRIGHT DEPOSfT. / J ANSWERS TO Questions Prescribed BY Pental State Boards BY ROBERT B. LUDY, M. D. PHILADELPHIA, PA.: CONOVER PUBLISHING HOUSE, 429 NORTH TENTH STREET, I902. > > THE LIBRARY »F GONGRr Two Copies Received APR. «g 1902 COPYWaHT eNTRV 5iU-. CUSS AyXXa No.. 1- L 2 3, 9 copy e. ■V \°\ 0^ Entered according to Act of Congress, in the year 1902, by Robert B. Ludy, M. D., in the Office of the Librarian of Congress at Washington. . • . . PREFACE. To pass creditable examinations is the laudable ambition of every earnest student. Many persons having an adequate knowledge of the subject in which they are tested, fail, because of their inability to inter- pret properly the intents and purposes of the questions to be answered by them. To aid in this, as well as to afford a convenient manual for the general preparation of Dental Students in their work, is the sole object of this book. Having collected a large number of questions from different States, it was found that duplications occurred ranging from 30% to 75%, vary- ing according to the several subjects. Thus a comprehensive knowledge of these questions and answers will serve excellently in the preparation for future examinations before such Boards. In order to secure a critical interpretation of the questions, and concise, yet complete, answers to the same, the author has been favored by the assistance of well-known specialists in their several lines, whose competence and experience give to the work a range and value impossi- ble of attainment in the product of a single author. It has been deemed advisable to unite all questions from the dif- ferent States under their respective headings,. so that undue repetitions of similar questions might be avoided. Although standard literature has necessarily been consulted, yet, in a work of this character, references would only prove cumbersome ; hence they have been generally omitted. To Drs. Rice, Greenbaum, Thomas, Newton, Boom, Buckley, Fritz and Good, the author makes grateful acknowledgement. The high value of their carefully prepared answers is fully appreciated by him, and will be, he is assured, by those into whose hands the work is com- mitted. The answers to the questions on " Special Dental Anatomy and Physiology," have been written by Dr. Herbst of Philadelphia. The author also desires to thank Dr. Roxby, Instructor in Anatomy at the Medico -Chirurgical College, for valuable assistance in the preparation of this work. Should the earnest students in Dentistry find aid herein in their efforts to succeed, the sincere wishes of the author shall be realised. R. B. LUDY. Philadelphia, April, 1902. SPECIAL AUTHORS- operative DENTISTRY.— By EARLE C RICE, D. D. S., Philadelphia. Professor of Dental Pathology, Therapeutics and Materia Medica in the Medico- Chirurgical College of Philadelphia(Department of Dentistry), and MAX GREENBAUM, D. D. S-, Philadelphia. PROSTHETIC DENTISTRY.— By Max GREENBAUM,D.D.S. ORAL SURGERY.— By W. HERSEY THOMAS, M. D., Phil- adelphia. Instructor in Surgery in the Medico- Chirurgical College of Philadelphia. PATHOLOGY and THERAPEUTICS— By EARLE C. Rice, D. D. S. PATHOLOGY.— By W. HERSEY THOMAS, M. D. flATERIA MEDICA and THERAPEUTICS.— By RODLEY D. NEWTON, Ph. G., M. D. Instructor in Anes- thesia and anesthetics in the Medico Chirurg-i- cal College of Philadelphia, and MAX GREENBAUM, D. D. S., Philadelphia. CHEHISTRY and METALLURGY.— By HENRY H. BOOM, M. D., Philadelphia, P-rotessor of Chemistry, Physics and Metallurgy in the Philadelphia Dental College. HISTOLOGY.— By ALBERT C. BUCKLEY, A. M., M. D., Philadelphia. Associate Professor of Histology in the Medico-Chirurgical College of Philadel- phia. ANATOMY.— By W. WALLACE FRITZ, M. D., D. D. S., Dean and Professor of Anatomy aud Clinical Surgery in the Medical Department of Temple College, Philadelphia ; Demonstrator of Anat- omy, Lecturer on Surgery and Chief Assistant to Medical Clinic in Philadelphia Dental College; Director of Philadelphia School of Anatomy, etc. PHYSIOLOGY.— By Wm. Harmar Good, A. B., M. D., Philadelphia, Demonstrator in Physiology at the Medico-Chirurgical College; Clinical Assist- ant in Medicine at the Samaritan Hospital, Philadelphia. CONTENTS. \ Page I OPERATIVE DENTISTRY i II PROSTHETIC DENTISTRY 45 III ORAL SURGERY 73 IV PATHOLOGY AND THERAPEUTICS 149 V PATHOLOGY 168 VI THERAPEUTICS AND MATERIA MEDICA 186 VII CHEMISTRY AND METALLURGY 224 VIII HISTOLOGY 260 IX ANATOMY :. 290 X PHYSIOLOGY AND HYGIENE 341 XI SPECIAL DENTAL ANATOMY AND PHYSIOLOGY, 382 OPERATIVE DENTISTRY. Describe method of cleansing the teeth. The oral cavities should first be washed with a 5% solution of hydrogen dioxide. Then with suit- able instruments all foreign substances should be removed from beneath the gum margin and upon roots. Then with a piece of orange wood, charged with pumice and an antiseptic, all the surfaces should be well rubbed, frequently rinsing the mouth with a suitable antiseptic. State the preferable material for fillings in cavi= ties beneath the gums. Give reasons for your choice. Gutta percha and amalgam. Gutta percha has made a notable record in these cases. It is non- irritating to the gum, does not necessarily require exclusion of moisture for its introduction and can be readily inserted. Amalgam, likewise, preserves teeth with such cavities, being easily introduced and not requiring absolute exclusion of moisture for its introduction. Give treatment of superior central incisors having small approximal cavities, when the teeth are in firm contact. The teeth are separated and gutta percha is used. Some operators claim that if the margins of these cavities be extended in accordance with the principle of " Extension for Prevention," they may be permanently filled with gold. 2 OPERA TIVE DENTIS TR Y. Give the technic of preparing an approximal cavity and filling it with a combination of gold and tin. The cavity is given proper retentive form and may be filled one-third or one-half with tin, after which gold is added to completion. Describe the method of examining the teeth of patients and mention the instruments used. All the surfaces including sulci and grooves are carefully examined by means of fine explorers and mirrors Floss silk is passed between the teeth to detect a roughened surface. State under what condition a matrix is essential in filling cavities. In distal compound cavities of bicuspids and molars, especially when plastics are employed. Define abrasion of teeth and give the method of restoration. A mechanical wearing down of teeth brought about either through faulty occlusion, excessive wear or some habit like gritting of teeth. The exposed dentine is properly prepared for foundation and the margins so trimmed as to allow of the covering of the entire surface with a gold filling. Describe the treatment of anterior teeth that are sensitive at the gingival border. If there is no erosion of tooth structure, various antacid mouth washes are recommended. Milk of magnesia is very good. In cases of erosion the places are properly prepared and filled. OPERA T1VE . DENTISTR Y. j State the proper treatment of teeth rendered sore from wedging. If they are too sore to permit of any work being done, gutta purcha may be introduced in the space and the teeth allowed to rest for 24 or 48 hours. Describe the method of filling a cavity in a first permanent molar having a partly exposed pulp. The cavity is rendered antiseptic .b}/ the use of a non-irritating agent, after which oxysulphate of zinc under a metallic cap may be gently laid over the exposure. Zinc phosphate is next introduced and allowed to harden after which the cavity is rilled with gold or amalgam. Or the cavity ma}^ be tem- porarily filled with zinc phosphate to determine the success of the capping operation. In what respect is non=cohesive gold preferable to cohesive gold for filling teeth? It is more readily adapted to the walls of the cavity. What advantage has amalgam over gold for f ill= ing teeth? It is decidedly easier of introduction. How should an amalgam filling in a compound cavity involving the approximal and masticating surfaces of a molar be inserted ? The use of a matrix will aid in keeping the ap- proximal portion of the filling in place while it is being introduced from the masticating surface. If allowed to remain for several hours it will guard against the filling being displaced during mas- tication. 4 OPERATIVE DENTISTRY. Give method of treating and filling a buccal cavity that extends beneath the alveolar border with adjacent soft tissues congested and bleeding. It may be necessary to introduce a temporary filling to press out and relieve the hyperemic con- dition of the gum, or rubber dam; then a clamp may be employed and the cavity filled at once. Give method of treating and filling a deep cavity when the tooth is sensitive, either to hot or cold. It is best to make an application of some seda- tive antiseptic and seal it in the cavity with tem- porary stopping for several days. When the normal condition of the pulp is restored, several layers of an impervious varnish should be interposed between the dentinal substance and the metallic filling. Give method of treating and filling a very sensi- tive superficial cavity with gold. The sensitivity should be reduced by some chemical agent like sulphuric acid in glycerine, 50%, after which the cavity is properly prepared and filled. Cataphoresis may also be resorted to. What are the comparative merits of hand and mal= let pressure? The hand pressure admits of more delicate deal- ing with the tooth structure and usually is not so severe in effect upon patients. The mallet enables us to work more quickly and usually results in bet- ter condensation of gold. OPERATIVE DENTISTRY. 5 Give method of removing pulps that have not been devitalized. By desensitizing with hydrochlorate of cocaine, pressure anesthesia, or else under general anesthesia. Give the treatment in case of pulp exposure at= tended with pain in deciduous teeth. The employment of a pledget of cotton dipped in oil of Eucalyptus, oil of Cloves or Carbolic acid, until we effect its devitalization. How should deciduous teeth be treated and filled ? In such manner as will insure their retention for a proper time. Filled preferably with the plastic filling materials. Give method of treating and filling approximate cavities in permanent teeth of children when these teeth are deficient in lime salts. Perferably, with gutta percha until such time when, after proper systemic treatment, we can fill with gold. Describe the method of preparing and inserting an amalgam filling. The alloy and mercury are carefully weighed and may be used in equal parts. The mixing of the two in this proportion generally yields a thoroughly plastic mass. A portion of this is introduced into the cavity and well adapted against the parietes, after which the mercury may be expressed from the re- maining portion, and, by introducing it against that first introduced, it will draw up the mercury. This may be repeated until the mass is thoroughly har- 6 OPERATIVE DENTISTRY. dened. The filling is polished at a subsequent sitting. State the advantages of amalgam over the other plastic fillings. Give reasons. It has a wider range of application and propor- tionately greater degree of durability. This is mainly due to its ability to withstand stress of mastication and insolubility in the oral fluids. State conditions under which amalgam should be used for filling. Give reasons. Wherever it is not exposed to view and where gold, for any reason, is not indicated. As amalgam fillings discolor, owing to formation or oxides and sulphides, the darkened appearance should not be exposed to view. What changes result after an amalgam filling is properly placed in a cavity ? Discoloration and the formation of a crevice along the margins which is more pronounced with some amalgams than with others. Describe method of treating and sterilizing a cavity for a filling, stating medicaments employed After the final preparation of the cavity, mois- ture must be excluded, after which pyrozone, satur- ated solution of thymol in glycerine, carbolic acid, or oil of cloves, may be employed. It must be borne in mind that antiseptics must be allowed to remain for some time in cavities to be decidedly beneficial. In what class of teeth should gutta percha, rather than metallic fillings, be used ? Give reasons. OPERATIVE DENTISTRY. . 7 In teeth where the pulp is still in a vigorous degree of formative activity. Metallic fillings by inducing thermal shock might result in destruction of the pulp and leave the tooth improperly formed. Describe the insertion and finishing of a gutta percha filling. The material should be warmed over a suitable warmer and introduced piece by piece. In finishing the material warmed, instruments should be passed over the surface, always directing them towards the margins, not from them. Solvents should not be employed in finishing. State the benefit derived from the use of nitrate of silver in operative dentistry. In hypersensitive cavities in deciduous teeth where no filling material can be inserted, this agent has proven of value. As an obtundent of hypersen- sitive dentine upon exposed surfaces. As a disin- fectant. Describe the operation in which sulphuric acid may be used. To wash out carious bone. In certain forms of pyorrhea alveolaris as a solvent for concretions upon roots, and to open minute root canals to permit of easier entrance. Give the causes and general treatment of dental caries. Lactic fermentation. Complete removal of decay, thorough sterilization of cavity, proper preparation and filling. 8 OPERATIVE DENTISTRY. What advantages has gold over other materials used for fillings ? Has excellent edge strength, does not alter its form after proper introduction, and is not affected by oral fluids. Preserves its color. What advantages has gutta percha as a filling material ? It admits of easy introduction. Conserves teeth permanently when properly used. Is non-irritant and non-conductive. What causes the deposit over an exposed pulp ? Any irritation which simply increases the func- tional activity of the pulp. Generally slight thermal shock. Is the deposit of secondary dentine physiologic or patholologic ? Physiologic, inasmuch as it is simply a revival of a normal function. Give treatment in case of alveolar abscess with fistula, acute and chronic. In the acute form, the opening is enlarged so that the seat of infection can be reached. It is washed out with hydrogen dioxide and packed with borated or sterilized gauze. The tooth is opened and pulp canals thoroughly antisepticized. In the chronic, after exhausting thorough anti- septic measures both through fistula and root canals, amputation of affected root has been recommended. Give treatment in case of pulpitis. If our various mild and powerful sedatives are OPERATIVE DENTISTRY* 9 unavailing, we may, under cataphoresis, force cocaine into the dentinal structure and expose the pulp; and, by inducing hemorrhage, produce relief ; after which it is devitalized. What is erosion ? Give its cause and treatment. A chemical disintegration of hard dentinal structure generally occuring upon the labial surfaces of the superior teeth. It is caused by the elimina- tion in all probability of acid sodium phosphate by the labial glands in consequence of a gouty or rheu- matic diathesis. If the destructive effect is suffi- ciently marked, these places must be filled. Antacids should be recommended in the mouth, and the patient be referred to the general practitioner for a thorough anti-gout or rheumatic regime. Give the etiology and the general preventive treatment of dental caries. Lactic fermentation. Proper cleansing of the oral cavity by removing all particles from the sur- faces of teeth by means of tooth brushes and pow- der, floss silk, and the use of proper antiseptics. How is dental caries classified ? Superficial, simple, deep-seated and complicated, involving exposure of the pulp. What is superficial dental caries ? Give treat- ment. That stage of decay which has not penetrated the enamel. Remove it by discs and stones and thoroughly polish the surface. io OPERATIVE DENTISTRY* What is deep=seated dental caries ? Give treat= ment. That stage of decay which would render likely irritation of the pulp through conductivity of thermal deviations. Remove all decay, properly sterilize, ap- ply several layers of varnish after cavity is formed, and properly fill. What is the best treatment to render a cavity antiseptic ? After removal of all decay and irrigating with hydrogen dioxide, it is best to seal in the cavity, for several days, a penetrating antiseptic like thymol in alcohol, glycerine or oil of cloves. Why does the application of nitrate of silver arrest decay of teeth ? It forms with the detinal substance an im- penetrable albuminate of silver which has high anti- septic property. Mow should a first permanent molar with inflamed pulp be treated in a child seven years of age ? If, after careful study of the articulation of the two jaws, it does not appear likely that its removal will interfere with normal occlusion, the tooth, if seriously affected, may be extracted. The second molar very likely will erupt in its place. It does not, however, appear probable that in a child seven years of age the first molar will have an inflamed pulp. Give the method of removing pulp and filling root canals in inferior molars with approximal cavities in distal surface. OPERATIVE DENTISTRY. n Sufficient tooth structure must be removed in order to have easy access to the canals. If various instruments at our command for extirpating the pulp are not adequate for the requirements, we may de- stroy remaining pulp filaments by pumping 50% sulphuric acid into canals and neutralizing with sodium bicarbonate. The canals are permanently filled with gutta percha, oxychloride of zinc or mum- mifying paste. At what age is it best to extract the first perma= nent molar ? Give reasons. If we find at any time before eruption of second permanent molar that the first is so seriously im- paired that there is no likelihood of its useful re- tention for any considerable time; and, if its removal will not bring about interference with the remaining normal occlusion, then it may be extracted to allow the second molar to erupt in its place. What is dental caries ? A chemical disintegration of tooth structure com- bined with a liquefaction of the remaining organic dentinal matrix through lactic fermentation and bac- teria that, by their excretions, have the property of dissolving organic substances. Describe the treatment of a tooth that is ex= tremely sensitive to thermal changes after filling. A gutta percha cap may be adjusted over the tooth and counter-irritants applied directly over the root of the tooth. If this is not sufficient to relieve the pulp hyperemia, the filling should be removed 12 OPERATIVE DENTISTRY* and sedatives applied in the cavity and filled tem- porarily until the pulp returns to normal condition. Give method of extracting a tooth with root so enlarged by exostosis that its removal through the socket must result in fracture. The gum tissue is raised and sufficient bony structure is drilled away to free the root. Give method of treating fissures in children's teeth before they are attacked by caries. They may be treated by applications of silver nitrate. When the walls of cavities have softened beneath approximal gold fillings extending beneath the gums, how should these cavities be treated and filled ? Remove affected tooth structure, apply antisep- tics and fill either with amalgam or gutta percha. Under what conditions is immediate root filling advisable ? When the pulp is devitalized and completely extirpated and there is no evidence of hemorrhage from the apical vessels. What anatomic changes are produced by the loss of the teeth ? Resorption of alveolar walls and consequent falling in of lip and cheek. The fullness of the region of the superior cuspids is lost and becomes very evident by a changed expression. The lower jaw comes forward. State the injuries that may result from wedging teeth. OPERATIVE DENTISTRY. i 3 Pericementitis and possible devitalization of pulp. What are the risks attending the devitalization of pulps by arsenic ? Leakage and consequent destruction of adjoining tissues. Give the most practical method of removing pulps from bicuspids and molars. Some of the canals in these teeth are often attenuated, making it difficult for the entrance of suitable instruments. After removing all possible with the finest broaches, mummifying paste may be applied without likelihood of any future trouble. Under what conditions in deciduous dentition is the lancing of the gums indicated ? Explain. In pathological dentition indicated by marked irritability and fretfulness of the child and hyperemic condition of gum tissue. Lancing relieves the resis- tance which the gum offers to the erupting tooth and allays the pathological features. Give a general rule for the preparation and forma= tion of cavities before filling, and name the points that require special care in excavating. Remove weak overhanging walls, and decay, and properly sterilize ; care must be exercised not to ex- pose the pulp unless decay has penetrated into its substance. The margin must be properly bevelled along the line of enamel cleavage and the cavities given retentive form. 14 OPERA TIVE DENTISTR Y. What are the diagnostic signs of a dead pulp in a tooth ? The development of acute septic pericementitis followed by acute alveolar dental abscess and the decid- ed clouding of the tooth. The latter generally being apparent before the existence of the former. Mention the class of operation in which a combi= nation of gold and amalgam is preferable to either material used separately. Explain. In approximal cavities extending well up under the gum tissue. Amalgam alone is too unsightly. Gold is very difficult to introduce under the gum. The amalgam is first introduced, and, after it has set, the rubber, is adjusted, the cavity being finished in. gold. In what respect is amalgam preferable to other plastic filling materials ? It has the quality of withstanding attrition and is practically insoluble in the fluids of the mouth. Why are the risks especially great in rapid wedg= ing of the superior central incisors ? There may be a separation of the superior maxillae and failure of the incisors to return to their normal position. The pulps may also become devitalized. What characteristic pain results from pathologic conditions of the pericemental membrane ? Pain upon pressure or tapping of tooth. What are the distinguishing symptoms of peri= cemental and pulp pain ? Pericemental pains are increased when pressure OPERATIVE DENTISTRY. i 5 is brought to bear upon the tooth. Pulp pain res- ponds to thermal variations. How should pathologic disturbance of the peri= cemental membrane be treated ? Removing the cause, giving rest to the tooth, applying counter-irritants at some distance. Seda- tives like tincture of Aconite may be applied directly over the affected tooth. How should pain resulting from pathologic condi= tions of the pulp be treated ? If the lesion is not severe, the cause of the pain is removed and guarded against ; sedatives are em- ployed in the cavity. If the condition is beyond con- servative treatment, then the pain is subdued and an arsenical application is made to devitalize. What classes of operation tend to induce patho= logic conditions of the pulp and membranes of the teeth ? Large gold fillings, for which considerable space must be prepared by extensive wedging and long continued malleting, may induce pericemental dis- turbances. Also, correcting irregularities, this may lead to pathological conditions of both pericementum and pulp. Excessive reduction of the enamel for crown and bridge work may further lead to pulp dis- turbances. What special precaution should be observed in in= serting gold fillings in approximal cavities of the teeth ? When the filling is completed it should properly restore the surface or shape of the tooth as well as touch the adjoining tooth ; the margins of the cavity j 6 OPERATIVE DENTISTRY. should be made self-cleansing in accordance with the principle " extension for prevention." They should also be made as inconspicuous as possible. What are the characteristic symptoms of neuralgia arising from a crowded denture ? Reflex pain generally felt in the ear and down the neck. What are pulp stones? Give treatment. Calcific formations generally within the body of the pulp. The treatment is devitalization and re- moval. How should a cavity be treated and filled when the dentine is highly inflamed ? A sedative should be placed in the cavity covered by a temporary filling. Describe in detail the method of restoring, with a combination of amalgam and cement, frail, broken crowns. Zinc phosphate is mixed thin and adapted in position, being careful to remove it from such places as would, after completion of the operation, expose it to the fluids of the mouth. Previously prepared amalgam is then worked into the setting zinc phos- phate in such a manner as will insure its retention. The filling is then properly contoured and finished. State the most efficient and satisfactory treat= ment of teeth that have become sensitive with tendency to decay under plate clasps. OPERATIVE DENTISTRY. i 7 Apply silver nitrate, caustic potash or zinc chlo- ride. It may also be necessary to cut out affected portion and fill with gutta percha. Give pathology and treatment of green stain on children's teeth, mentioning the medicament used. The remains of the enamel cuticle is invaded by bacteria, and in their development produce a green coloring material, staining the surface of the tooth. Teeth should be thoroughly polished, removing the remnants of Nasmyth's membrane, also, the slightly roughened surface beneath. Peroxide of hydrogen or tincture of iodine in combination with pumice, will be found useful as aids to remove discoloration. Why do pulpless teeth loose their natural hue? Give a remedy for preventing this change. It is due to disorganization of the red blood cor- puscles and their absorption into the dental tubuli, following the death of the pulp. Also the formation of various substances that act as discoloring agents. The sulphide of iron may be formed which produces the yellow discoloration. If after devitalization, the tooth is treated with a 25% solution of pyrozone, and a lin- ing of white oxyphosphate of zinc is introduced, much may be done to keep the color of the tooth. Differentiate pyorrhea alveolaris and salivary calculus. Give the cause, prognosis, and treatment of each. Pyorrhea alveolaris means a flow of pus from the socket of the tooth, but the disease itself embraces certain other characteristic features. There is necro- j 8 OPERATIVE DENTISTRY. sis of alveolar walls and pericementum and a pro- gressive loosening of the tooth. Salivary calculus merely signifies an accumulation of calculus coining from the salivary fluids and deposited around the cervical margins of the teeth. It may lead to a form of pyorrhea by irritating the gum tissue and making the site of its location favorable for septic formations, in connection with which we would find pus forma- tion, necrosis of alveolar walls and pericementum and a gradual loosening of the tooth. The prognosis is favorable. The treatment consists in removing all deposits, inducing antisepsis ; if the teeth are con- siderably loosened, they may be held quite firmly by means of bands. In the other forms of pyorrhea, the prognosis is not favorable. Generally there is a sys- temic complication which should receive adequate attention. Locally, the treatment is practically the same as in the first grade. Give directions for the general care of the mouth and teeth of children. Directions should be given for the proper use of the brush, and a suitable tooth powder. The teeth should be bathed, at least in the morning and before going to bed, with a suitable antiseptic wash. And,, furthermore, frequent examinations should be ad- vised. At these examinations, which may be con- ducted monthly, the surfaces of the teeth should be thoroughly polished. How should crooked buccal root canals be treated and filled ? 50% sulphuric acid should be utilized to effect as thorough an opening of the canal and removal of OPERATIVE DENTISTRY. i 9 pulp as is possible. If this means does not allow of reaching apical ends, then a mummifying paste may be introduced. When should a pulp be devitalized and when capped, and why ? The dental pulp should be devitalized when it becomes the seat of such circulatory changes as ultimately would lead to its death, indicated by con- tinued paroxysmal pain markedly aggravated by applications of heat. If left alone, it would die and subsequently become the centre of septic processes, causing acute septic pericementitis and alveolar den- tal abscess. The dental pulp should be capped when we find an exposure without evidence of serious compli- cations, such as would make clear the necessity for devitalization. Furthermore, the pulp should be capped if in the preparation of the cavity it is acci- dentally exposed. This conservative treatment is favored because it insures translucency to the tooth, vitality to the dentine, and a general immunity to septic complications. How would you prepare and fill proximal cavities with frail wall to the cutting edge in the anterior teeth ? Frail walls that will not admit of proper adapta- tion of gold should be removed until strong tooth substance is reached. In this a proper anchorage can then be made and the tooth filled. How would you relieve excessive sensibility of the dentine? 20 OPERATIVE DENTISTRY, Hypersensitive dentine is treated by two general classes of remedies, anodynes and caustics. In the first group we have the essential oils, campho-phe- nique, and various alkaloidal preparations ; in the second, carbolic acid, chloride of zinc, caustic potash,, nitrate of silver and equal parts of sulphuric acid and glycerine. The anodynes are employed when nearness to the pulp precludes the use of caustic ap- plications. In very obstinate cases hydrochlorate of cocaine may be driven into the dentinal structure under the electric current. General anesthetics may also be utilized in very stubborn conditions. It is also well to bear in mind that sharp instruments modify these painful impressions. When are artificial crowns and bridges indicated and when not ? When in the anterior part of the mouth a tooth becomes objectionably discolored and cannot be res- tored in color through the various bleaching pro- cesses. In the posterior portion when a tooth is so far gone as to preclude useful restoration by filling materials. Bridges are indicated when one or more teeth have been lost and we are able to utilize firm roots or crowns at each end of the space for support. Under no circumstance should bridges be adjusted when the abutments do not meet this indication. What effect does salivary calculus have upon the teeth and gums ? Its accumulation causes resorption of alveolar walls and consequent loosening of teeth. It induces hyperemia of pericementum and gum tissues, as well OPERATIVE DENTISTRY. 21 as necrotic changes, by favoring retention of septic material. What diseases may arise from a putrescent pulp? How should such teeth be treated to restore them to use= fulness ? Acute septic pericementitis followed by acute alveolar dental abscess. In acute pericementitis an opening is made leading to the putrescent pulp for the escape of the various products formed in the putrefactive process. This, together with the seda- tive effect of an application of the tincture of aconite to the gum tissue, and the counter irritating effect of tincture of iodine applied some distance from the affected area, and the use of antiseptic astringent mouth washes, usually afford relief. After this, ef- forts are made to thoroughly cleanse and sterilize the root canal or canals. Peroxide of sodium, peroxide of hydrogen, or formalin, in varying strengths, are carefully introduced. When no odor can be detected it is well to introduce a temporary cotton dressing, the non absorbent variety, carrying upon its surface campho-phenique, or a saturated solution of thymol in glycerine. After a few weeks a permanent canal filling of gutta percha, oxychloride of zinc, or some antiseptic paste may be employed. If we are dealing with an acute alveolar abscess, which is usually diag- nosed in the early stages by the existence of a throb- bing pain, then the first indication is to rid the part of the pus. This is accomplished by making an in- cision through the gum tissue and with the engine burring through the alveolar wall until an outlet for 22 OPERATIVE DENTISTRY. pus is secured. Or we may adopt the slower method of overstimulating the gum tissue by the use of the pepper bag, and thus by reducing its resistive force invite a passage for the pus. After the outlet for the pus is secured, then all the preceding antiseptic mea- sures indicated in the treatment of acute septic peri- cementitis are rigidly followed. Describe your method of preparing and filling approximate cavities in bicuspids and molars. The first essential indication is to secure suffi- cient space through separation. In simple cavities the margins had better be extended in accordance with the principle — " extension for prevention." In compound cavities the use of the matrix frequently abridges an otherwise protracted filling operation. Furthermore, the general principles applicable to all cavities must ever be present in the mind of the operator. These are thorough removal of decay, sterilization of cavity, proper formation as to reten- tive as well as marginal requirements. What are the principal causes of irregularities in teeth ? Name two typical cases and describe your treat= ment. The causes of irregularities are hereditary and acquired. Chief among the acquired causes is early loss of deciduous teeth, also such habits as thumb sucking and lip sucking. We may have, as a result of too early loss of deciduous teeth, the permanent cuspids standing outside of the arch. As the result of thumb sucking, the superior incisor teeth may OPERATIVE DENTISTRY. 23 stand outside of their normal line and the lower ones inside. In case of the irregular cuspids the removal of the first bicuspid very frequently is sufficient to cause the cuspid to assume its normal place. Or by adjusting a Magill band upon the first or second molar with a tube soldered to it, and a like appli- ance for the lateral incisor. A bar connecting these teeth with a pin soldered about half way and then securing attachment to the cuspid and adjusting a rubber band, this tooth readily comes into its normal place. In case of the outstanding incisors the Ma- gill band is made for each lateral with an exten- sion over the central. A vulcanite plate is next made for the roof of the mouth with the portion appoximating the lingual surfaces of the incisor teeth cut away to allow for their posterior movement. In the center of the plate a good hook is fastened and then by means of rubber bands these teeth are drawn backwards. Decribe the difference between cohesive and non= cohesive gold, and state when indicated separately or in combination. Cohesive gold is so prepared as to permit of the thorough welding of one piece to another. Non- cohesive gold does not admit of this, because some foreign substance is deposited upon its surface. Non-cohesive gold is used when we have all the walls of the cavity standing and they are strong en- ough to resist the force of the wedge principle adopted in its condensation. It may also be employed as a foundation in a filling to be completed with cohesive gold. 24. OPERATIVE DENTISTRY. How should cervical cavities be prepared with reference to the gum margin ? It is well to extend the margin of cervical cavi- ties beneath the border of the gum. In this way they are better protected from decay. When and how should a pulp be devitalized ? A paste of arsenious oxide, hyrochlorate of co- caine and an essential oil is generally employed to devitalize the pulp. Give method of treating a pulp canal containing putrescent pulp. Putrescent pulp is best treated by applications of peroxide of sodium or formalin (10%) followed by temporary dressings of thymol in glycerine until the canal is completely sterile. State methods of filling pulp canals. The materials most generally used are chlora- percha followed by warm gutta percha cones, or oxychloride of zinc mixed in and introduced upon threads of aseptic cotton or aristol and wax. State the best methods of applying gold to the walls of cavities in poorly calcified teeth. Dr. Black's experiments have quite conclusively shown that there is no such condition as a poorly calci- fied tooth. The difference in the percentage of lime salts of over a thousand teeth was practically the same. But some teeth appear to be poorly organized. In such teeth the dentinal substance is cut most readily and when gold is used, It is better adapted if we first use a lining of oxychloride or oxyphosphate of zinc. Sometimes, non-cohesive foil is first used followed by cohesive gold. OPERATIVE DENTISTRY. 25 How should a freshly exposed pulp be treated ? After carefully sterilizing the cavity with hydro- gen peroxide a paste of zinc oxide and oil of cloves is prepared ; this is gently applied over the exposure, after which several layers of an impervious varnish are used. Zinc phosphate may next be flowed over this, taking great care not to exercise any pressure. The cavity is then filled according to indications. What advantages are claimed for a combination of gold and tin as a filling material ? Tin foil is more readily adapted than cohesive foil and furthermore, it markedly reduces the con- ductivity of the filling. What causes pericementitis ? Give treatment. Pericementitis is most frequently caused by the entrance of septic matter from the pulp canal into the tissues of the apical space. The treatment con- sists of opening the pulp canal, removing the con- tents and destroying all septic matter by the use of such agents as sodium dioxide, hydrogen dioxide, formalin or thymol in glycerine. Powerful counter- irritation to the gum with tincture of iodine, sedation by means of tincture of aconite and surgical rest to the affected tooth. Under what conditions of the dentine is a plastic filling preferable to gold ? Excessively hypersensitive dentine may be bet- ter filled with a plastic filling. How should a pulp be devitalized by arsenic when decay exists below the soft tissues ? 26 OPERATIVE DENTISTRY. By pressing out soft tissues and filling that por- tion of the cavity with temporary stopping, after which arsenic may be applied without danger to the soft tissues. Give diagnosis of irritation from pulp stones. Continued acute paroxysmal pains without re- lief from strongest sedative applications. Give method of extracting the roots of an inferior third molar when the crown is broken off and the gums swollen. An incision may be made buccally and lingually through the gum tissue and dissected from the underlying structure. In this way we may extend the forceps down some distance and get a firm hold ; then by an upward and backward movement, we can dislodge the roots, or use an elevator. What are the best materials for filling decidu- ous teeth ? The plastic filling materials. Describe the method of treating decay in decidu- ous teeth. Remove as much of the decay as would be con- sistent without encroaching upon the pulp, then wash with peroxide of hydrogen or touch with silver nitrate. Finally fill with a plastic filling. Give the treatment of exposed pulp in deciduous teeth of a child six years of age. As it is important to conserve the pulp as a means of maintaining aseptic conditions in the canal and thus favoring resorption of the deciduous roots, / OPERATIVE DENTISTRY. 2? it is best to first take all antiseptic precautions and then cover the exposure with a paste of zinc oxide and oil of cloves, after which zinc phosphate may be flowed in the cavity. Describe method of bleaching a central incisor. 2 5% pyrozone may be used with or without the cataphoric current, or what seems to be in favor with many practitioners is sealing the apical foramen and inserting chlorinated lime and a solution of either acetic or oxalic acid and allowing this to remain in the cavity about twenty-four hours. Close up care- fully with zinc phosphate. Give method of restoring the edges of incisors that are worn away by friction. Preparing a foundation in the dentine and bevel- ing outwardly the enamel margins so that gold pro- tects the entire incisal surface. How should cavities be prepared and filled, involv- ing approximal and occlusal surfaces ? All weakened overhanging walls of enamel should be trimmed away, and the margins of the cavity extended to a point where they can be easily reached in cleansing. No grooves should be made in the approximal part of the cavity, as they would weaken the walls. The occlusal portion should be made retentive in form — dovetailing rather than grooving. At the gum margin, the floor of the cavity should be flattened to make a firm ledge for the fill- ing to rest upon. Such cavities, if deep, should be varnished and lined with oxyphosphate of zinc before inserting a metallic filling. 28 OPERATIVE DENTISTRY- Describe carefully the condition requiring the de= vitalization of the dental pulp. The method you pursue and precautions necessary. A pulp which has been exposed by caries should be devitalized with arsenic, which is applied in a minute quantity in combination with such sedative agents as acetate of morphine, or muriate of cocaine y made into a paste with one of the essential oils. Great care should be taken to hermetically seal this preparation in the cavity, to prevent its coming in contact with the gum tissue, pericementum or alveolar process. When it is possible to do so, rubber darn should always be applied before the application is made. Give the etiology and treatment of an apical alvec- lar=dental abscess. The etiology or cause of an apical alveolar-dental abscess is the invasion of pyogenic organisms into the already inflamed apical space, gaining access either through a carious cavity, or through the circulation. The treatment is first, the removal of the contents of the pulp cavity and canals and the cleansing of the abscess cavity, which should be washed with x% pyrozone. The canals of the tooth should be thor- oughly sterilized with sodium dioxide, followed by 10% sulphuric acid. A temporary dressing of thymol and menthol should then be placed in the canals, and the tooth given surgical rest. If, in the course of a few days, tenderness disappears and there is an ab- sence of pus, and the dressing removed from the tooth emits no purulent odor, the canals may be perma- nently rilled. OPERATIVE DENTISTRY. 2 9 How would you treat deciduous teeth with exposed pulps ? If the exposure of the pulp of a deciduous tooth be small, and the pulp not giving evidence of ex- treme pathological disorder, the pulp may be capped and an attempt made to preserve its vitality in order that root resorption may not be interfered with. If, on the other hand, the exposure of the pulp be large and accompanied by marked pulp disorder, the pulp should be destroyed with iodine, and the canals filled with paraffine and aristol. How would you diagnose a diseased or dead pulp in an apparently sound tooth ? Diseased pulps may be diagnosed by their altered response to the thermal test. Dead pulps do not respond at all to these tests. In doubtful cases, how would you distinguish a temporary one from a permanent tooth ? An examination of the enamel edge at the neck of the tooth will show a thickened ridge, if the tooth be a temporary one. If permanent the enamel will bevel off to a feather edge. How would you prepare and fill approximal cavity with frail walls extending to the cutting edge of an incisor? All frail margins of enamel should be trimmed away. The labial margin of the cavity should be brought to the cutting edge in a direct line. The cervical aspect of the cavity should be prepared as a flat ledge, whose base is at right angles with the jo OPERATIVE DENTISTRY. longitudinal axis of the tooth. The lingual margin should follow the direction of the labial to within about 1-16 of an inch of the cutting edge, where it should turn at right angles, and pass across the tooth at the cutting edge to a point a little beyond the depth of the cavity. The lingual layer of the enamel only is removed. A slight groove is- cut in the inci- sal portion, and a pit sunk at its extremity. The labial plate of enamel should be beveled from within outward, and likewise, all of the other margins ex- cept cervical, which should remain as before stated — flat and at right angles to the longitudinal axis of the tooth. A starting point, if gold is to be used, may be made in this surface of the cavity. If caries has not advanced too for, the cavity may be prepared in the form of a dovetail at the cervical end. The fill- ing may now be started at this part of the cavity with non-cohesive or cohesive gold, and built squarely to a point where the greatest fullness of contour will be made. The progress of the filling should then be towards the groove and pit in the cutting edge, and a sufficient bulk of gold laid on, to give strength to re- sist necessary malleting on the cutting edge. The filling may now be finished without fear of dislodging by malleting. By this method of preparation, the filling material has a broad flat substantial base upon which to rest, and resists lateral stress by virtue of the pit and groove on the occlusal edge. Is lancing the gums indicated in dentition ; if so, under what condition ? Lancing the gum is indicated in dentition when OPERATIVE DENTISTRY. ji there is an extreme inflammatory condition of the gnm over the tooth about to erupt, which is the cause of sufficient discomfort to impair the health of the child. Describe the process of replanting teeth and pre- cautions necessary ? Replanting a tooth, (the return of a tooth to the socket from which it was extracted) must be con- ducted with extreme antiseptic precaution. The tooth should be first carefully extracted, the beaks of the forceps being guarded by small pieces of spunk. The tooth should be placed in a warm antiseptic solu- tion, r to 2000 bichloride of mercury. If this method is employed for the cure of alveolar abscess, the alveolus should be thoroughly cleansed with warm antiseptic spray, and any portion of the sac which may have been retained, removed. The portion of the root which has been denuded of pericementum should be cut away, and the surface polished. Great care should be observed not to injure the remaining normal pericementum. The tooth may now be re- placed in its socket, and firmly held for a few days by ligatures, and a bolus of oxyphosphate of zinc cement. During the entire process of replantation, the mouth should, from time to time be carefully sprayed with such antiseptic preparations as phenol sodique, listerine, etc. Describe the method of treatment in painful pulp exposure. The cavity should be thoroughly washed with warm antiseptic solutions, and such excavating done 32 OPERATIVE DENTISTRY. as will 'give the cavity a retentive form. A paste of muriate of cocaine and Ceylon oil of cinnamon is then placed over the pulp, protected by a pellet of cotton. Over this should be flowed enough thinly mixed oxy phosphate of zinc to cover the cotton. When the cement has set, the balance of the cavity may be filled with temporary stopping. If after twenty. four or forty-eight hours, the pulp exhibits no marked hyperesthesia, an application of arsenic should be made and the pulp destroyed. Describe the diagnostic signs of dead pulp in a tooth, when there is no pulp exposure. Dead pulp may be diagnosed, when there is no pulp exposure, by lack of response to the cold pro- duced by ethyl chloride spray ; also by the electric mouth mirror, demonstrating a marked opacity of the tooth. Describe the operation of implanting, and the pre= cautions necessary. The operation of implantation consists in pre- paring an artificial cavity in the gum tissue and max- illary bone, where a natural tooth, carefully selected as to size and shade, is to be inserted and firmly held until nature has deposited a calcific matrix around it. The precautions necessary are thorough asepsis, not only of the tooth to be implanted and of the artificial socket, but also of the entire oral cavity, and instru- ments used in the operation. Name the probable cause of erosion of the teeth, and give the treatment. The probable cause of erosion of the teeth is an abnormal acid secretion by the glands in the inner OPERATIVE DENTISTRY. jj surface of the lips, destroying the tooth substance. The progress may be arrested by the milk of mag- nesia as a mouth wash before retiring. The cav- ities occasioned by erosion should be rilled with gold or gutta percha. When is protection to the denal pulp from thermal changes indicated, and how is it accomplished ? Protection to the dental pulp from thermal changes is indicated when that organ responds in an exaggerated degree to the application of heat or cold. In the treatment of teeth containing cavities, the cavities should be varnished, and lined with cement before metallic fillings are inserted. In a tooth not containing a cavity, the adjoining teeth should be wedged from it, a cap of gutta-percha placed over it, and allowed to remain until the pulp regains a nor- mal condition. Describe method of securely anchoring a gold fill= ing in a distal cavity with frail palatal walls, in a vital superior cuspid. Anchorage may be secured by removing a nar- row parallel strip of the labial plate of enamel at the occlusal edge, not disturbing the labial wall. Groove the dentine along this excavation and sink a pit at its mesial extremity A groove should also be made at the cervical end of the cavity. This anchorage will resist all stress applied anteriorly. How may an inflamed living pulp be diagnosed and located when no cavity exists ? The rubber dam should be applied and the tooth exposed to applications of both heat and cold. The 34- OPERATIVE DENTISTRY, pulp will respond with a paroxysm of severe pain to the heat, with less severity to the cold. In these cases where no cavities exist, the pericementum is usually affected, and responds to percussion. The history is usually as follows : The tooth has been subjected to traumatic injury, and later became slightly sensitive to touch ; still later vague pains in the pulp appeared, gradually increasing in severity. Describe the treatment of excessive hemorrhage following tooth extraction. Excessive hemorrhage after extraction may be suppressed very successfully by the following method : A roll of cotton dipped in sandarac varnish and thickly powdered with tannic acid is packed firmly into the alveolus, and allowed to remain for a week or ten days. If, upon withdrawing the cotton plug, hemorrhage is resumed^ the alveolus should be thoroughly cauterized with a thermo-cautery, and a second plug inserted. Fluid extract of ergot may be prescribed internally in drachm doses. How would you decide whether to cap or devitalize a partially or completely expos d pulp ? If a pulp is partially exposed by caries after thorough antiseptic precautions have been taken and the pulp rendered normal, it should be capped, tem- porarily filled, and carefully watched for six months or a year. If it remains normal for that time, the cavity may be permanently filled. Pulps com- pletely exposed by accident while excavating, which do not come in contact with the fluids of the mouth y may be successfully capped. Pulps completely ex- OPERA TIVE DENTIS TR Y. j 5 posed by caries should be invariably devitalized. Describe minutely your treatment and manner of capping a pulp. With the rubber dam applied, the cavity should be thoroughly cleansed and rendered aseptic by the use of a thymol solution. The cavity should then be thoroughly dried, and a small concavo-convex piece of copper, gold, lead, or platinum rilled with a mixture of zinc oxide and oil of cinnamon placed over the exposure, and sealed with zinc oxysulphate cement. This should be again covered with oxy- phosphate of zinc, the cavity being first varnished w r ith a solution of amber in chloroform. Fill the cavity temporarily, and if, in six months, the condi- tions are favorable, a permanent filling may be in- serted. Describe your method of treatment and manipula- tion in devitalization and extirpation of the pulp, and fill= ing the canal. Apply rubber dam, and remove as much of the carious contents of the cavity as the patient will per- mit. A small exposure should be made, and a minute particle of arsenic in combination with cocaine muri- ate and oil of cinnamon applied to the exposed sur- face. Protect the application with a soft pellet of cot- ton, and seal with temporary stopping or thinly mixed oxyphosphate of zinc cement. In forty-eight hours, if the pulp shows no signs of vitality, again apply the rubber dam, remove temporary filling, and with thoroughly clean burs, expose the whole of the pulp chamber. The body of the pulp is now re- j6 OPERATIVE DENTISTRY. moved, and with, barbed pulp extractors, extirpation of the root portion is accomplished. The canal or canals should be washed with sodium dioxide solution, fol- lowed by aromatic sulphuric acid, and then dried with alcohol and warm air. A few shreds of cotton wound upon a broach and dipped in chloro-percha solution , should be carried into the canals. Repeat this sev- eral times until the chlora-percha has been pumped to the apex of the canals. Cones of solid gutta-percha are then inserted in the canals, and the tooth tem- porarily filled. If in forty-eight hours no pericemen- tal disorder is manifest, a permanent filling may be inserted. Describe under what conditions you would place crowns upon natural roots, and your method of procedure. Crowns are indicated when the natural crown of the tooth has been so far destroyed as to prevent its restoration by filling. If some portion of the natural crown remains, and the tooth is situated posterior to the cuspid, the crown may be partially restored with amalgam, and a hollow metal crown attached. Or, if the pulp be not vital, and the tooth be anterior to the first molar, the root may be cut off to the gum line and a Richmond crown, supported by a strong platinum pin, inserted. To prepare a root for a hol- low metal crown, all the enamel should be removed, and the tooth so trimmed that its greatest diameter will be at the cervical margin. At this point, the measurement for the band is taken with binding wire. This is accurately measured upon a piece of gold plate 29 or 30 gauge. A strip of gold is then cut the OPERATIVE DENTISTRY. 37 desired width, is curled, and the ends sweated or sol- dered. This is placed upon the tooth root and marked to the festoon of the gum line. The band is then removed and trimmed to this line with curved shears. A cap is now swaged to articulate nicely with the occluding tooth, and is soldered to the band. The whole is then trimmed and polished. In pre- paring a root for the Richmond crown, the same prin- ciples are involved as to the beveling, measuring and cutting of the band, which, when soldered, is placed upon the root, festooned and driven to place by press- ure or tapping. The labial aspect of the root and band is now beveled down to a point beneath the gum margin to conceal the joint which is to be made be- tween gold and porcelain. A piece of No. 30 gauge, 24 carat gold is burnished over the root and band. The band is now removed and soldered to the cap. The platinum pin is now thrust through the cap into the canal of the root. A porcelain facing is selected and ground to an approximate fit backed with 24 carat, 30 gauge plate. Allow the backing to extend all the way to the gum margin. This should now be cemented to place upon the cap with hard wax, cooled and the whole removed. It should now be in- vested, the bulk of the wax picked out and the bal- ance allowed to burn awa}^ while heating up. Apply borax and solder with evenly distributed tempera- ture. The general principles in the construction of all crowns, which are modifications of these two men- tioned, are herein embodied. What (if any) possible evils may arise from pre- j8 OPERATIVE DENTISTRY. mature extraction of temporary teeth ? Malposition or impaction of the permanent teeth may result from premature extraction of temporary teeth. Name the different materials used in filling teeth, and the conditions in which the use of each is indicated, either separately or in combination. Oxysulphate of zinc is used in pulp capping. Oxychloride of zinc is used as a lining medium for very deep cavities covered with oxyphosphate of zinc, which in turn is an admirable cavity lining where caries has not approached too near the pulp. Ox}^- phosphate of copper is well adapted for cavities in children's teeth, where absolute dryness cannot be obtained, and is an excellent temporary stopping in teeth that do not admit of thorough excavation. Tin is a good filling material indicated in the teeth of children. Amalgam is used in posterior teeth and in invisible parts of anterior teeth, for nervous patients who cannot submit to long operations, also in frail teeth. Gold alone is only indicated where cavities exhibit strong hard surfaces. In combina- tion with the oxyphosphate of zinc and amalgam it may be used in nearly all cases. Gold and platinum in combination are indicated in large anterior cavities where the color of gold is objectionable. Gutta per- cha is used as a filling material for children's teeth, and is also well adapted for cavities near the gum margin, on the labial, buccal and lingual surfaces of the permanent teeth, and as a root canal filling. Par- OPERATIVE DENTISTRY. 39 affine in combination with aristol is also employed for this last mentioned purpose. Give a general rule for the preparation of cavities before filling, and name the points that require special care in excavating. All overhanging, weak enamel margins should be trimmed away, and carions dentine removed from the cavity. The margins of the cavity should always be extended to a point where recurrent caries is least apt to occur. Grooves or dovetailed excavations should never be made in the enamel. Special care should be observed in excavating, not to encroach upon the pulp. If a layer of dentine over the pulp be decal- cified and not carious, it should be thoroughly steril- ized and allowed to remain. What are the diagnostic signs of dead pulp in a tooth ? How would you treat such a tooth and restore it to usefulness ? When a tooth fails to respond to applications of extreme heat or cold, the pulp is dead and should be extirpated. Extreme antiseptc precautions should be observed in this operation to avoid peridental in- volvement. The canals should be treated with so- dium dioxide followed by aromatic sulphuric acid, thoroughly dried with alcohol and warm air, or an electric root-drier, and filled. What is the usual cause of discoloration of teeth ? Describe in detail your method of bleaching. Discoloration of teeth is usually caused by death of the pulp and infiltration of coloring matter of the 40 OPERATIVE DENTISTRY. red corpuscles into the dentinal tubuli. Apply rubber dam, remove all decalcified dentine, thoroughly cleans- ing the canals. Seal the apices of the canals with gutta percha. The cavity should now be thoroughly washed with a solution of caustic soda, and then dried with absolute alcohol and hot air. This drying pro- cess should continue until the dentine is thoroughly desiccated to a considerable depth. A pellet of cot- ton saturated with a 25% ethereal solution of py- rozone is now placed in the cavity and allowed to re- main for fifteen or twenty minutes. The cotton should then be removed, and the cavity again dried with hot air. This process should be repeated several times until the tooth is seen to become bleached, when a saturated solution of zinc chloride should be placed in the cavity and allowed to remain for a few mo- ments. The tooth should again be dried with alco- hol and hot air, and filled with dead white oxyphos- phate of zinc. After a few days, part of the zinc phosphate in the tooth crown is removed (not expos- ing the dentine at any point) and the tooth per- manently filled. What is pulpitis ? Give the etiology, symptoms and treatment. Pulpitis is the condition of a pulp which is un- dergoing the last stages of inflammator}^ change. It is caused by deep metallic fillings and traumatism ; first appearing as active hyperemia, then congestion, after which diapedesis and the pouring out of inflam- matory effusions occur. The symptoms are throb- bing pain and exaggerated response to heat. The OPERATIVE DENTISTRY. 4 i treatment consists in the administration of- anodynes, blood letting over the affected tooth, and sedative ap- plications to the pulp. The prognosis, however, is not favorable in these cases. How would you correct a case of excessive protru= sion of the upper teeth ? If there is not sufficient space to draw the teeth directly back into position, the first bicuspids should be extracted and the cuspids drawn backward by means of jack screws, until they occupy the vacant spaces made by the extraction. The four anterior teeth may now be drawn back simultaneously by rubber bands attached to a cap placed upon the occi- put. A retaining plate should be made to hold the teeth in position until they are firmly fixed. Give the treatment for a child ten years old whose central incisors are broken, so that the pulp is exposed. The essential consideration at this age is to con- serve the vitality of the pulp. The exposed parts should be bathed in peroxide of hydrogen, after which a capping of zinc oxide mixed to a paste with oil of cloves or campho-phenique is applied ; next several layers of an impervious varnish are placed over the capping and the operation completed with a zinc phosphate filling. At a subsequent period, that is, when the tooth is fully formed, a more lasting filling may be introduced. How should a congested pulp be treated ? A congested pulp, or one which is the seat of venous hyperemia, evidenced by a continued dull 42 OPERATIVE DENTISTRY* pain, particularly responsive to heat, should be treated by first allaying the pain and then devitalizing. How should the margins of cavity wall be pre- pared for an amalgam filling ? The margins should be so prepared that the amalgam in its adaptation is not worked to a feather edge. What are the dangers attending the devitalization of pulps by arsenic ? Escape of the arsenic and destroying surround- ing tissue. How should arsenic be applied in cases where the cavity extends beneath the gum ? That portion of the cavity extending beneath the gum should be filled, arsenic should not be placed in a cavity beneath the gum, as leakage is very likely to take place in such location. It is better to make the application in such location as can, after devital- ization, afford ready ingress to the pulp canals. Give the best methods of keeping cavities dry. By the adjustment of rubber dam. At times the introduction of napkins is sufficient to keep cavities dry, as, for instance, in short operations in mouths which do not seem to collect the saliva in lar^e quantites. Give the recognized stages in the preparation of a cavity for filling. Securing proper space for the necessary work through separation. OPERATIVE DENTISTRY. 43 Removal of all weak and overhanging walls. Removal of all decay and proper sterilization of cavity. Proper marginal preparation. Regard for possible pulp complications through conductivity and pressure of filling. Describe method of filling an occlusal cavity in molar with shallow sulci radiating from deep central cavity. De= scribe the form and condition of gold used in the operation. The cavity is enlarged to include all sulci so that when finally prepared it is star shaped. It may be filled with cylinders of non-cohesive gold, or with the cohesive variety either in the form of pellets or foil. Designate a class of cavities in frail teeth where a combination filling of gutta percha and zinc phosphate is indicated and give technic of operation. Cavities extending beneath the gum tissue. The gutta percha is placed in that part of the cavity situ- ated beneath gum tissue, and the zinc phosphate oc- cupies the remaining portion. Mention the causes of shock by cold or heat to teeth recently filled. Give treatment. Thermal deviations through metal fillings owing to improper protection of dentinal substance. A gutta percha cap may be adjusted over tooth, and counter irritants applied to gum ; if this does not effect a cure, the filling should be removed, sedatives applied in the cavity, the dentine properly protected by the use of an impervious varnish, after which the cavity is filled. • 44 OPERATIVE DENTISTRY. What are the physical changes in an amalgam filling after its insertion in a tooth ? It hardens, changes its form and changes its color. Give treatment of inflammation of pulp in a su= perior central incisor that has a gold filling in good condi= tion in the approximal surface. An opening may be made from the lingnal sur- face where the basilar pit is located, and an arsen- ical application made ; after devitalization, the pulp is extirpated through this opening which is enlarged for the purpose. When the pulp of a tooth has sloughed leaving a discharge through the cavity of the tooth, how should the tooth be treated and filled ? It should be treated with peroxide of sodium or strong solution of formalin until every vestige of dead and decomposed tissue has disappeared. It may then be temporarily filled with concentrated solution of thymol on cotton and a temporary filling. If after four weeks everything appears satisfactory, the canals and cavity may be permanently filled. PROSTHETIC DENTISTRY. Describe the method of constructing a banded Lo= gan Cuspid Crown. After the root is properly prepared a facing of pla- tinum is accurately fitted to its surface. A band is next prepared and these two are soldered together. The labial aspect of the Logan Crown is ground to fit the root, so that when the crown is introduced into posi- tion, it will be found to fit the labial portion of the root, whilst lingually it will stand away from the root. The lingual portion of the crown next may be ground on a level after which a thin piece of platinum is perforated by the dowel and burnished against the base of the crown. A little hard wax is melted upon this piece of plate to keep it in position. The band and facing are placed in position upon the root and the Logan Crown is forced into place. The parts are then removed, invested, the hard wax is removed and solder poured in its place. What materials are used to produce the gum color in porcelain ? Principally purple of Cassius. Describe the method of repairing a continuous gum denture. The denture is first cleansed of any foreign sub- stance. This is best done by placing the denture in the oven and slowly heating to redness which car- 46 PROSTHETIC DENTISTRY. bonizes all organic substances upon the plate. It is then thoroughly washed in soap and water. The broken tooth is next ground until the original stay is exposed. A new tooth is selected, accurately ground in position, backed and soldered to the original attach- ment. After this, the body is added and the case becomes just as good as when first made. Describe the process of sweating' together two pieces of gold plate of the same degree of fineness. The ends are beveled and brought together and by the careful application of heat may be united through partial fusion of surfaces in contact. What relation should the artificial teeth bear to the alveolar ridge? The tooth should be so arranged that its long axis is in line with the vertical axis of the ridge, to that the direction of force will be in the line of the centre of gravity. In retaining plate by the clasp method, is it better for the clasps to fit the teeth perfectly or merely to touch the teeth at several points ? State reasons. The clasps should be so fitted as to touch the teeth at as many points as it is possible to make them touch. This gives the greatest support. If the}' but touch the teeth at several points, they will soon, through wear, not touch at all and prove inadequate in main- taining the plate in position. Describe a denture for a person having sound canines and second molars. A horse shoe shaped plate may be constructed in such a case with clasps fitted to the second molars. PROSTHETIC DENTISTRY. 47 What causes gold and silver plates to warp while soldering ? How may this warping be prevented ? It is caused by contraction of the solder. The plates should be firmly imbedded in an investing material. Why is platinum used for pins in teeth ? Its expanding and contracting ratio is about that of the porcelain teeth, and its high fusing point en- ables it to stand the heat of tooth baking. What gauge metal is used for an upper denture? What for a lower? About 26 for an upper, and preferably two thick- nesses of 30 or 32, soldered together, for the lower. Describe in detail the preparation of teeth for re= planting, transplanting and implanting, and your method of performing each operation. The tooth should be sterilized by immersing it in a 1- 1 000 solution of bichloride of mercury or 10% formalin. The contents of the pulp canal are re- moved and the canal is filled preferably with gutta percha, so as to seal out all foreign substances. After sterilizing the socket, the tooth is pressed into place and retained with a crib or splint. Sometimes the root is shortened as in cases of implantation. Replanting is replacing and securing in position a tooth which has been extracted for some pathologi- cal condition. This may be done after the socket has been prepared in a manner previously indicated. Transplanting is the process by which a tooth is ex tracted from one mouth and is placed into an existing 48 PROSTHETIC DENTISTRY. socket in another month. Implanting is the process of inserting a tooth which has been extracted from another jaw, into a socket prepared by drilling into the bony strnctnre at a point where a tooth has been previously extracted. The general antisep- tic measures and treatment of the tooth referred to above shonld be carefully observed. Describe a method of repairing the gold plate when the only remaining incisor is to be extracted and replaced by an artificial substitute. After the removal of the tooth, the plate is re- placed and an impression is taken with plate in situ. When the model is made the plate will appear upon it. The soft tissne may be cnt away to allow for sub- sequent resorption and the tooth properly fitted and attached. Describe construction of a gold bridge to replace teeth lost between cuspid and second molar, both named teeth being in place and available. The natural teeth are properly ground, and, for the cuspid, a jacket is made ; while, for the second molar, a gold crown is prepared. 22-carat gold plate is employed. With these in position, an impression is taken ; after securing the proper articulation and shade of teeth, the model is made and the two jaws articulated. The facings are ground to properly fit, their cusps are re- moved, and gold cusps are prepared to take their places. This gives strength to the piece when completed. After backing the facings, the parts are invested, soldered and finished. PROSTHETIC DENTISTRY. 49 Is there any objection to the use of silver in com= bination with vulcanite ? The sulphur in the rubber leaves the latjier and combines with the silver forming silver sulphid. The thin layer of the rubber being thus deprived of its sulphur cannot become vulcanized and remains soft. What would you do to prevent a plate from rock= ing in a mouth with a hard palatine ridge ? If the plate is vulcanite, it may be scraped at such points which rock upon the tissues. If metal, it may be reswaged by placing several folds of paper along the hard ridge on the die. How would you mix plaster of Paris for im= pressions ? Warm water may be used to hasten the setting of the plaster and material is added to the water until there appears to be no excess of water. For lower impressions it may be mixed slightly stiffer. A small quantity of sodium chloride on potassium sulphate may be used instead of warm water. flention the three principal ingredients used in manufacturing porcelain teeth and state which one gives translucency and lifelike appearance to the teeth. Kaolin, Feldspar and Silex. The Feldspar is used to produce the enamel and gives the translu- cency. What metal is used as a coloring agent to produce the grayish blue tint of the enamel of artificial teeth ? Platinum. jo PR OS THE TIC DEN TIS TR Y. State the relative merits of gutta percha and cement in retaining crown or bridge work in the mouth. Gutta percha is rapidly advancing in importance as a means of securing attachment for artificial crowns and bridges. It is insoluble, affords a means of ready removal in case such step is necessary, and acts as a cushion during periods of stress, preventing the fracture of porcelain facings. It has the good features of cement, with additional ones added, with- out the bad features of cement. Cement often proves irritating to the pulp, is brittle if used in small quan- tity and absorbs the fluids of the mouth and becomes offensive. Describe a method of obtaining a correct die from a lower model that has several anterior teeth standing, the jaw very much undercut lingually below the necks of the teeth. The teeth are cut down on the model, and, by making two cores approaching each other at the cen- tre of the model, we are able to accurately reproduce the model in either zinc or Babbitt's metal. What would result if an upper denture extended too far posteriorly and touched the palate ? In the act of talking or swallowing, movement of the muscular tissue of the soft palate would be likely to displace the plate, and at the same time cause retching. What is the difference between platinous gold and platinized gold ? Platinous gold is the alloy of gold and platinum. Platinized gold is a combination of gold on one side PROSTHETIC DENTISTRY. 51 and platinum on the other, rolled together. What is plaster of Paris chemically ? How pre= pared for dental purposes ? Sulphate of calcium. Finely ground and de- hydrated. Give the fusing points of tin, zinc and lead. Tin, about 460 ° F.; lead, about 617 F.; zinc, about 7^° F. What is meant by the interdental spaces ? The triangular space between teeth partly occu- pied by gum tissue. Give method of striking up a partial gold plate. Having the die and counter-die prepared and the plate in the form ready for fitting, it is annealed and the portion projecting over the ridge for the support of the artificial teeth is first bent over, the plate is then worked into position by means of pliers and the mallet, and after it approximately fits the die, it is swaged between the die and counter-die. What is a metallic die? The reproduction of the model in metal. Give the fusing point of gold. 202 1 ° Fahrenheit. (Hodgen.) Describe your method of crowning the root of a superior central incisor. The Richmond crown is here indicated. The root is properly prepared and sides dressed and a platinum piece is fitted to its face. If the crown is to be made with a full band, then this part is next $z PROSTHETIC DENTISTRY- fitted and soldered to the platinum facing. If the half band is made, it is made at the same time the facing is fitted to the root. The platinum is allowed to ex- tend beyond the lingual aspect and bent over, and by cutting a V into this extension it may readily be formed into the half of a band. , The dowel is next adjusted in the enlarged pulp canal and the dowel and facings are soldered. It is then placed in posi- tion (taking a wax bite) and if everything is properly related, an impression is taken with the adjoining tooth on each side represented and a model made. A facing is next selected, ground, backed, invested and soldered. What carat solder is obtaind by fusing together 10 parts pure gold, 3 parts copper and 2 parts silver? Carrying the proportion contained in the above to 24 carat, it represents 16 carat solder. Can you solder an 18 carat plate with 20 carat solder ? Explain. As the 20 carat solder has a fusing point slightly above the 18 carat plate, there is every likelihood of fusing the plate in the attempt to make the solder flow. What is the substance known as vulcanite ? It represents the caoutchouc minus its hydrogen which the admixed suphur removes in the process of vulcanization. Give the method of setting a Bonwill Crown. The dowel is first set with amalgam or zinc phosphate and allowed to project beyond the face of PROSTHETIC DENTISTRY. 53 the root so that it may extend into the perforation fonnd in the Bonwill Crown. The crown may then be set with either of the above materials. When should plain and when should gum teeth be used ? The gnm tooth is employed when the patient, in laughing or talking, markedly displays the teeth. The artificial gum more closely resembles the natural gum than vulcanite. Plain teeth are employed when the reverse is the case ; they may then be embedded in vulcanite, and as the lip effectually covers the rubber, it is hidden from view. Give the fusing point of silver. About 1904 Fahrenheit. (Hodgen). Describe the best method of re=enforcing the por- tion of a gold plate, lower partial, that crosses behind the six anterior teeth. By swaging an extra piece of gold plate to fit the lingual aspect and rest about one-third up on the teeth and solder this to the plate. State some of the first considerations in exami- nation of the mouth preparatory to making an artificial denture. The mouth is examined as to its condition of health. Diseased roots that are beyond being made useful should be removed. The question of permit- ting the cuspid roots to remain in place requires serious consideration. A molar, or a molar on one side and a bicuspid on the other, will be found very useful in keeping the denture in place. These Si PROSTHETIC DENTISTRY. points, as well as the existence and relation of soft and hard tissues, should be duly considered. State how plaster may be prevented from dropping into the throat while an impression of the upper jaw is being taken. By having the patient lean forward, or in adjust- ing a heel of wax to the impression tray. State the percentage of caoutchouc and of sulphur used in making vulcanizable rubber .suitable for dental plates. Caoutchouc 48 parts, sulphur 24 parts. Should gold clasps be used about a tooth contain- ing a large amalgam filling? Explain. The gold in apposition with the amalgam is apt to produce a galvanic current and shock the pulp. State two essential requirements for the produc- tion of a perfectly fitting artificial denture. An accurate impression and an accurate model. How should a plaster model be treated when a portion of the ridge is soft and the centre of the mouth hard ? The soft portion should be slightly scraped to produce compression when the plate is introduced. State some of the causes of fracturing porcelain teeth during the process of soldering. Not sufficiently heating the teeth before attempt- ing to make the solder flow. In cooling too quickly the tooth contracts before the pins have contracted. By allowing borax to come in contact with the por- celain during soldering. PROSTHETIC DENTISTRY. 55 Describe the difference between long bite teeth and short bite teeth. Hention cases where each would be appropiate. Long bite teeth have a much greater distance between the occlusal surface and the pins than be- tween the pins and the cervical border. In short bite teeth the reverse holds good. Long bite teeth are indicated where the natural teeth in one jaw bite up close to the alveolar ridge in the opposite jaw. Short bite teeth would be appropriate in a long alveolar ridge and short lip. Which is finer, 20 carat plate or 20 carat solder ? Which fuses at the lower degree of heat ? Why ? Both have 20 parts of pure gold in 24. The solder fuses at a lower degree of heat than the plate, because zinc is incorporated with it. The gold plate has no zinc. How may rubber be prevented from entering the joints between gum sections ? By filling up the spaces with oxychloride of zinc. Give some of the uses of zinc, lead, Babbitt's metal. Zinc is used as a die in the swaging of metal plates. Lead is used as the counter-die in the swag- ing of metal plates. Babbitt's metal is used as a die particularly in cases where we do not wish any contraction of the die to influence the fit of the plate, as in the case of zinc dies. Give a method of removing a Richmond Crown in order to repair the broken porcelain. jd PROSTHETIC DENTISTRY. The backing maybe grasped in the beak of a forceps and by a gentle rotation loosened and re- moved. If the crown is set with gutta percha, a warm instrument may be held in contact with the backing and the gutta percha sufhcently softened in this way to allow of the removal of the dowel, or drill through the cap and sever the dowel. What is the best investment for crown and bridge work ? Combination of plaster, 3 parts ; marble dust, 2 parts ; and clay, 2 parts. Some advise adding pumice. How soon after extraction of teeth should a plate be inserted ? The temporary plate may be introduced from four to six weeks after extraction. The permanent from between six to twelve months. What is the guide in the selection of artificial teeth ? The temperamental characteristics of the patient will guide us in the selection of color, size and shape. The length of ridge and the difference in length be- tween the high and low lip line will determine whether we use a short or long bite tooth, a plain or gum tooth. What is the guide as to the amount of rubber to be packed in a case ? If the case has been carefully waxed, the wax when removed may be weighed, and, by using an amount of rubber just slightly in excess of this, we PROSTHETIC DENTISTRY. 57 closety approximate the amount of rubber needed. Or, in bringing the two halves of the flask gradually together, the surplus may, by opening the flask from time to time, be trimmed away until finally there remains about the correct quantity of rubber. Should light shades of teeth be selected for the blonde or for the brunette ? Why ? The various pigmentary deposits throughout the system are generally harmonious. In the blonde we are apt to find light shades in teeth to correspond with the color of the skin and hair. Dark shades would be inharmonious in the blonde, and vice versa. How should the loss of a superior lateral incisor be replaced ? A jacket is made for the cuspid and to this the artificial lateral is attached. Give a method of making a gold clasp. Gauge about No. 24 is selected and adapted to that portion of the tooth determined by its shape. If the tooth be a bicuspid or molor a lug is fitted in an occlusal groove to prevent the clasp from working up and irritating the gum tissue. What effect on the shade of teeth has platinum backing and a gold backing ? Platinum tends to darken. the shade of the tooth. Gold tends to brighten it. Why is silver not used in crown and bridge work ? Crowns and bridges generally being fixed, the oxides and sulphides that would form could not be properly removed. SS PROSTHETIC DENTISTRY. What is the amount of alloy in American gold coin ? American gold coin being" about 22 carat fine, the amount of alloy would be about two parts. (21.6 carat.) Give the method of cleaning and sterilizing burs. The adherent detritus may be removed by means of the wire brush, after which they are subjected to the heat of boiling water for thirty minutes, rendered alkaline by the addition of soda, or, are immersed in 10% formalin for 20 minutes. Describe the size, shape and shade of teeth suit- able for a person of bilious temperament. Large square teeth, angular cusps, close con- tact, and of a bronze yellow shade. What are the advantages of the continuous gum ? Cleanliness and the better artistic restoration of the lost parts. What is a counter=die ? The reverse of the die. Describe an air chamber as to size, shape and posi- tion. The air chamber, or more property, the vacuum chamber, is generally located from the point back of the rugae to about one-quarter of an inch from the posterior border of the plate. It describes the out- lines of the plate. Name the objections to the use of celluloid as a base plate. PROSTHETIC DENTISTRY. 59 Instability, porosity, loss of color and warping. Describe Brown's Porcelain Bridge, stating ad- vantages and disadvantages. The Brown Bridge consists of porcelain teeth connected by a bar of iridio-platinnm, and, subse- quently, united to this metal and to one another by the fusing of porcelain. Its advantages are that there does not exist the same liability to fracture as is found in the facings used in the ordinary bridge, and furthermore, it is supposed to be more cleanly. Its decided disadvantage is that, in the majority of cases, anchorage is secured by drilling cavities into natural teeth and fitting extensions into these cavities. Give method of setting a Richmond Crown. This crown may be set either with zinc phos- phate or gutta percha. If this crown is made with a full band, care should be exercised that no surplus material is allowed to irritate the pericementum. What is the best method of taking partial im= pressions ? For partial plates, impressions may be taken in wax and plaster. The impression being first taken in wax, then having the palatal portion trimmed down to allow of a small quantity of plaster being placed in position, after which the tray is reintro- duced and we have easy withdrawal with an accurate impression of the roof of the mouth and teeth. What advantages, if any, have Richmond Crowns over other crowns ? The Richmond Crown admits of accurate adap- So PROSTHETIC DENTISTRY. tation against the face of the root, producing a natural effect, and, by means of the half band, or in some cases the full band, prevents fracture of the r6ot. The gold employed also adds strength. What may be said in favor of pinless teeth ? Against them ? The pinless teeth possess the advantages of admit- ting of easy repair in case of fracture ; not having the gold backing, they present a cleaner surface and have a more natural appearance/ The disad- vantage seems to be, that in the anterior portion of the mouth very frequently the tube is too far front and the tooth does not entirely cover the face of the root. Give the fusing point of copper. About 2,ooo° Fahrenheit. Of what is Babbitt metal composed ? Copper, i part ; antimony, 2 parts ; tin, 8 parts. Where and how is crude rubber obtained ? Caoutchouc is a milky exudate from several spe- cies of trees found in tropical countries. The juice is collected and heated to drive off the water and allowed to stand, becoming elastic when exposed to the air. Give the method of obtaining an impression of a perforated, hard plate. I Plaster mixed quite stiff is carried into the nasal cavity and made even with the borders of the fissure. The tray with additional plaster is then introduced. PROSTHETIC DENTISTRY. . 61 At the first sign of setting, by a quick sudden move- ment, the impression can be made to separate at the line of the fissure. Afterwards, the two portions of the impression can be united. Give formula for silver solder. Silver, 3 parts ; brass, 1 part. What would be the effect of placing a piece of lead on a gold plate during the process of annealing? It would combine with the gold, and, by forming an alloy of a considerably reduced fusing point, it would burn a hole in the plate. Does absorption of the a veolar process advance more rapidly with or without a plate ? Without a plate absorption advances more evenly and quickly than when a plate is worn. In soldering a small piece of gold to a larger piece on which should the solder be placed ? Why ? By placing the solder on the larger piece of gold we may more readily invite its flow towards the smaller piece, because the larger piece is harder to heat up than the smaller piece. When vulcanite upper plates crack, why does the crack usually occur at or near the median line? Because the sides of the alveolar ridge are ab- sorbed and the median ridge of hard palate is not. Give the method of polishing a vulcanite plate on the palatine surface. Use. fine pumice and brush wheel. Can rubber attachments be placed equally well on gold, silver, or platinum base? 62 PROSTHETIC DENTISTRY. Rubber attachments can be made with, these metallic bases. Platinum, on account of the absence of rigidity, does not answer well unless alloyed with some metal. Silver requires the protection of some intervening tin foil, so that the sulphur of the rubber will not affect it. Gold is probably the best. Mow should faults be corrected in the articulation of artificial teeth ? If we carbonize the occlusal surface of the teeth of one jaw, they will show the points at which they touch first when articulating the two jaws. This may be repeated until they come evenly in contact. Give a formula for 2o=carat gold plate. Pure gold, 20 parts ; copper and silver each 2 parts. Describe the method of obtaining a correct bite for a full upper and lower set. Having the proper contour of lips and cheek and correct lengths, the patient's head is inclined back- ward and pressure exerted against the chin to pre- vent biting out. The patient may be asked to swal- low or hold the tongue back towards the pharynx. This, in a measure, prevents the common tendency of biting out with the lower jaw. Describe fully the method of preparing a molar tooth for a gold crown. Sufficient tooth structure must be removed to make the tooth fully as wide, if not wider, at the cer- vical border as at any other point upon the crown. This is generally accomplished by the use of the PROSTHETIC DENTISTRY. 63 diamond disk and corundum, carborundum or gem wheels of varying sizes. In the case of healthy central incisor roots, should Bonwill, Richmond or Logan Crowns be adjusted ? Give reasons for your choice. The Richmond Crown is the best, because it ad- mits of best adaptation to the root, possesses strength, and, by means of the half band or full band, prevents fractnre of root. The Bonwill Crown is too fragile. The Logan Crown is serviceable, but does not allow of the same accurate apposition with the root as the Richmond, and does not, unless prepared with a band, prevent fracture of root. How is gold solder confined to the desired sur- face? By careful application of borax of proper consis- tency. Proper application of heat, or, by coating sur- face not desired to have solder flow to, touched with a little jewellers' rouge. Describe a gold plate with a rubber attachment. The plate is swaged in the ordinary way, and, after the borders of the plate have been accurately marked, gold wire is soldered a^ong the alveolar outline and at the line of the termination of the rub- ber. This insures support to the rubber and makes likely a more acceptable finish. At selected points, gold wire is soldered to the plate ; or, scrap gold may be used. These are so arranged as to form a secure attachment for the rubber. The teeth are arranged as in any other case, after which it is vulcanized. 64 PROSTHETIC DENTISTRY. Give a formula for a 22=carat solder. Gold, 22 parts; copper, i part; silver, ^ of i part ; zinc, J4 of i part. State the reasons for using black, red, and pink rubber. It is claimed that black rubber is not so apt to prove as irritating as other varieties. The pink rub- ber more closely resembles the gum tissue and is used in the anterior part of the mouth. When the black rubber is objectionable, on account of its color, red rubber is used. What base for an artificial denture do you con= sider hygienically the best, and why ? Platinum covered with porcelain, commonly known as " continuous gum." On account of its thermal conductivity, lack of porosity and absence of spaces for accumulation of food particles. Gold plate with vulcanite attachment comes next in order of hygienic value. Describe the method and material you would use to secure a perfect model of the inferior maxilla when frac= tured. Take plaster impression of parts as found, and make plaster model. When the superior cuspids are outside a contracted arch, how would you expand the arch and bring them into position ? Expand laterally with coffin split plate, or, with bands on each side of arch with bent piano wire spring reaching from one side to the other. Or, in- PROSTHETIC DENTISTRY. 63 stead of piano wire spring a jackscrew may be used. With vulcanite plate covering the arch, a spring may be passed outside of the arch on each side to rest upon and press cuspids inward. What general principles should be observed in arranging artificial teeth for an edentulous mouth ? 1. Teeth should be of proper shade and size to suit the special case. 2. They should be so arranged as to occlude properly. 3. They should restore the expression of mouth and face. 4. They should be so placed as not to keep jaws too far apart, or, to allow them to come too close together. 5. To avoid tilting, teeth should be situated as nearly on centre of ridge as possible. Describe method of attaching metal clasps to vul= canite plates. Bend clasp to shape. Solder an ear or extension to it pointing toward the centre of the mouth. Punch holes in ear, fit it tightly to plaster tooth and vul- canize it to the plate. Can rubber be vulcanized in contact with silver? Give explanation. If the rubber is in direct contact with silver, in the process of vulcanization, the sulphur will attack the silver, for which it has great affinity, and will not properly remove the hydrogen from the caoutchouc, leaving the latter in a softened condition. 66 PROSTHETIC DENTISTRY, When an upper impression is to be taken, state the position of (a) the patient, (b) the operator. The patient is placed with head forward so as to prevent any plaster, if this material be used, from entering into the trachea. The operator is back of the patient. What relation in regard to length should (a) thie upper teeth bear to the upper lip, (b) the lower teeth bear to the lower lip ? The superior incisors are placed so as to extend about 1-16 or 1-32 of an inch below the upper lip. The inferior incisors are placed about the same distance below the lower lip. In articulating a full denture, what teeth should bear the greatest pressure of the bite ? The posterior teeth. The impression being ready, tell how to make the cast. The plaster is mixed to the proper consistency and a small amount is placed at the highest point of the impression, and carefully permitted to run into all parts of the impression, particularly into the im- pressions of any teeth. In this way a perfect model of all parts is secured. The air is thoroughly forced out and air spaces are avoided. Enough plaster must be added to give requisite strength to the model ; and,, by inverting the impression and plaster, and placing it upon a smooth surface, preferably glass, an even base surface is produced. About what degree of heat is required to fuse por- celain in continuous gum work ? PROSTHETIC DENTISTRY. 67 About 2600 F. Describe the method of constructing a porcelain faced bicuspid crown. A band or ferrule is prepared as for the hollow metal crown, the buccal portion is cut out, leaving the band intact at its cervix to a depth of about 1-16 of an inch. A cross pin cuspid tooth is selected and accurately ground to fit the portion of the band cut out. Its sides are then beveled and a backing of 30 gauge gold plate adjusted. This is held in position by means of hard wax applied within the band. An investment of plaster and marble dust is made, the hard wax removed, and the tooth soldered to the band. Having secured the articulation, the cusps are next prepared, secured in proper position, the different parts invested and soldered. How are teeth attached to the platinum plate in continuous gum work ? After the teeth are ground into position, they are secured in place by an investment ; the wax is removed and the platinum plate is so arranged that it is in contact with the plate proper as well as with the bent pins of the teeth. Pure gold is used to solder the parts. Why is the lower denture more troublesome than the upper denture ? There is little alveolar ridge, and there are ab- sent the advantages accruing from the presence of a vacuum chamber. What is weighted rubber, and where is it used ? 68' PROSTHETIC DENTISTRY. Rubber prepared with tin filings to give the finished plate additional weight,. Used in lower cases to overcome the ten den cv of the muscles and the sub- lingual tissues to displace the plate ; or, where the bite is unusually short and the stress is liable to fracture, the ordinary vulcanite plate. Mention the most desirable carat and gauge of plate for crowns. 22 K, gold; 30 gauge. In full dentures, are the upper or the lower teeth first arranged on the model ? Why ? The upper teeth are first arranged. Having the proper fullness of lips and cheek and proper lengthy. the upper teeth are ground into position, having the upper properly arranged, the lower set may then read- ily be ground to correctly articulate with the upper. State what causes gum sections to break in the flask. Generally due to excessive force employed in screwing down the flask. What is the fusing point of aluminum ? About 1200 F. What causes dark joints in gum teeth ? Not having filled the spaces between the joints, with some material that prevents the entrance of rub- ber in vulcanizing. What causes the tissues to infiame under a rub= ber or celluloid plate? Some claim that as these materials are very poor conductors of heat they permit an increased heat in PROSTHETIC DENTISTRY. 69 the parts. More likely it is due to the irritation of septic matter which finds lodgment on the surface of the plate next to the roof of the mouth. State what you consider the most unfavorable conditions for wearing artificial teeth ? Mouth with shallow arched and narrow alveolar ridges, where it is difficult to procure the effects of a vacuum chamber, and where the two jaws are re- lated as in marked superior or inferior protrusion. Describe the size, shape and shade of teeth suit= able for an elderly man of lymphatic temperament. Large, broad, ill shaped and flat, yellow color. Describe the teeth suitable for a young woman of nervous temperament. Small, or medium, conical, pearl blue or grey in color. How should an aluminum plate with rubber attachment be made ? The plate is swaged, care being taken not to fracture the metal either by overheating it in the an- nealing process, or by too forcible swaging ; the wire for holding the rubber is next soldered in the position it is to occupy. The soldering is difficult and is only correctly executed after the exercise of much care and time. After this, the teeth are arranged in the ordi- nary manner and the case vulcanized. Mention conditions which render the extraction of teeth advisable. Excessive looseness through loss of pericemen- tum or alveolar walls ; or, the seat of such disease jo PROSTHETIC DENTISTRY. which renders likely their early loss; or, a single in- cisor tooth which, if allowed to remain, would make difficult the arrangement of the artificial set, and fur- thermore enhance the artificiality of the new teeth. Describe the operation of extracting incisors, cus= pids, bicuspids and molars. All teeth with single and rounded roots are re- moved by a rotary movement. Those with flattened single roots by an in and out movement. The su- perior molars are removed by an out and in move- ment. The out being first employed. The lower third requires an up and back movement. Flention some of the accidents which may follow the extraction of the teeth. Fracture of roots, or of maxillary bones ; injury to gum tissue, infection of socket through lack of antiseptic precautions. flention some of the conditions which necessitate special precautions in extracting teeth. Crowded teeth where the forceps cannot be prop- erly adjusted. Impacted teeth. Crowns with frail walls require special precautions to prevent fracture. What kind of a denture should be constructed in the case of a patient whose superior canines and second molars are in position ? By devitalizing the pulps of the cuspids, remov- ing the crowns and preparing Richmond crowns for the roots, and then preparing hollow metal crowns for the second molars ; a bridge may be constructed extending from molar to molar, or a horseshoe plate ma} r be made with clasp fitted to the second molars. PROSTHETIC DENTISTRY. yi How should the loss of a superior lateral incisor be supplied in the case of a young woman ? It may be implanted ; or, by preparing a jacket for the cuspid and accurately fitting it, and so arranging it that only a very narrow width of gold is visible labially ; or, by the later method in connec- tion with which no gold is visible, an incisor may then be attached to the jacket. How are porcelain teeth attached to a metallic base ? By adjusting a backing, and then, by means of solder, attaching this backing to the pins and plate ; or, by having a rubber attachment to the metallic base and securing the tooth by means of this attach- ment. Give reasons for your preference of gum teeth or of plain teeth in full dentures. When the patient in laughing or talking largely displays the natural gum, then gum teeth should be used as this more closely resembles the natural gum than any other material. What is the fusing point of platinum ? About 3500 F. Give method of taking an impression of a root for a gold crown. Thin wire is adjusted around the root and drawn together until it measures the root circumference. If the inferior centrals are absent, how may the loss be supplied without a plate ? 72 PROSTHETIC DENTISTR K A jacket may be constructed for each lateral and the missing incisors fitted into place and soldered to jackets. How may a gold clasp be attached to a rubber plate ? After the metal is fitted to the tooth, at a con- venient point, is soldered an extension of gold or clasp metal. This extension is carried into the sub- stance of the rubber, and, in being perforated at sev- eral points, is securely held in place. How may plaster teeth on models be strengthened to prevent fracture ? By forcing a pointed wire or ordinary pin into the impression. When the model is run each tooth has this support extending into the model as well as through the tooth. ORAL SURGERY. What conditions are necessary to obtain bony consolidation after fracture ? Accurate apposition of the fractured surfaces without the interposition of pieces of muscle, connec- tive tissue or an excessive amount of blood clot, im- mobilization for a sufficient length of time, sufficient blood supply to both fragments, sufficient innerva- tion, absence of surface inflammation and constitu- tional causes of non-union. Asepsis is greatly to be desired, but bony union can occur in suppurating wounds by a process analogous to the healing of wounds by second intention. In what stage of inflammation is cold a valuable remedial agent ? Give reasons. Cold is a valuable remedial agent in the begin- ning of inflammation since it causes a contraction of the blood-vessels and therefore lessens the amount of blood in the part. If applied for too long a time, it lowers the vitality of the tissues, promotes stasis, and interferes with the ameboid action of the leucocytes. At what age are the best results obtained from operations for cleft palate ? Give reasons. The best results are obtained by operating be- tween the second and third years. It is not advisable to operate upon infants since they stand hemorrhage poorly, suck the stitches and disturb them with the 7/ ORAL SUR GBR Y. tongue, and because the tissues are delicate aud fri- able. It should not be deferred later than the period indicated as bad habits of articulation will be con- tracted and subsequent success, as gauged by the quality of the speech, is much less likely to follow. Differentiate lacerated and contused wounds. A lacerated wound is a wound produced by a tearing of the tissues. A contused wound is a wound produced by a bruising of the tissues. In practice the distinction is not well drawn, since the edges of most lacerated wounds are also more or less contused. State the predisposing causes of lingual carci= noma. . Age of the patient (past 40), any irritation, such as a sharp tooth, the stem of a pipe, or a badly .fitting plate ; psoriasis and scars produced by syphilis, in- jury, or any other cause ; smoking. What are wounds and how are they classified ? A wound is a solution of continuity of an exter- nal or internal surface of the body. Wounds are classified as follows: Incised, lacerated, contused, punctured, poisoned and gun- shot. Give varieties of fracture of the inferior maxilla. Through the body of the bone in the neighbor- hood of the mental foramen, at the angle or within the vertical ramus, through the neck of the condyle;, and at the base of the coronoid process. ORAL SURGERY. 75 Describe the operation for ligating the facial artery. After all aseptic precautions have been carried out, a horizontal incision, one inch in length, is made directly over the vessel as it crosses the lower border of the jaw immediately in front of the masseter. The incision divides the integument, the fascia, and the platysma myoides. In making the incision, the skin should be drawn upward over the bone, so that when the skin retracts, the scar will not be visible upon the face. The vessel is ligated just as it emerges from the substance of the submaxillary gland. The aneu- rism needle is passed from behind forward. What is anesthesia ? Anesthesia is a condition of total or partial in- sensibility, particularly to touch. Define synovitis. Give symptoms and treatment. By synovitis is meant the inflammation of a synovial membrane. Symptoms. — The joint becomes the seat of lan- cinating pain and is filled with fluid. If the articu- lation is superficial, the overlying skin may be hot and hyperemic. There is a spasm of the surround- ing muscles, causing the joint to be held in that posi- tion which affords the greatest ease to the patient. In some cases, the muscles controlling the joint undergo a rapid atrophy. If suppuration occurs, the overly- ing integument becomes dusky red and edematous. The pain becomes throbbing in character, and the individual is frequently awakened at night by start- ing pains in the extremity. The temperature is high and there is emaciation. j6 ORAL S UR GER Y. Treatment. — Immobilization. In the early stages and in young people, cold is of value (evaporating" lotions, ice bag r Leiter's tubes). Later on, warm fo- mentations may be used or a few leeches applied. If painful distention is present > some of the fluid may be aspirated under strict aseptic precautions. Should suppuration occur, the joint must be opened, irri- gated, and a rubber drainage tube introduced into- the most dependent portion. Any underlying diathesis should receive appro- priate constitutional treatment. Descrbe the ape rati an far I i gating the temporal artery. Make a vertical incision one incli in length, a half inch in front of the tragus, and just above the zygomatic arch. Divide skin, superficial fascia and deep fascia, and then feel for the pulsation of the vessel. The aneurism needle is to be passed from behind forward so as to avoid the temporal vein and the auriculo-temporal nerve. Give the varieties of gangrene. i. Symptomatic gangrene : embolic, senile, dia- betic, Raynaud's disease, ergotic. 2. Traumatic gangrene : direct and indirect. 3. Infective gangrene : acute rapidly spreading gangrene, hospital gangrene, necrosis of bone, noma and cancrum oris, carbuncle and boil. 4. Thermal gangrene : frost-bite, burns, and scalds. Name the different methods for arresting arterial hemorrhage. ORAL SURGERY. 77 Direct pressure, acupressure, forcipressure, tor- sion, cauterization, and ligation. Is necrosis found more frequently in the inferior or in the superior maxilla ? Why ? Necrosis is found rather more frequently in the inferior maxilla because its blood supply is not so abundant. Differentiate a syphilitic ulcer of the tongue from a traumatic ulcer of the tongue. Syphilitic ulcer. — There is a superficial crack or fissure upon the side or tip of the tongue. Such fis- sures may be multiple, chronic, or relapsing. It is common in the secondary period of the disease, and is often accompanied by mucous patches, by similar ulcers upon the cheeks, or by papular eruptions upon the skin. It improves under specific treatment. Traumatic ulcer. — The ulcer is usually situated upon the side of the tongue, is ragged or irregular in outline, and is usually opposite a collection of tartar, an angle of a tooth, or the edge of a plate. The glands are not enlarged. Recovery follows the re- moval of the local irritant. Define orthodontia. By orthodontia is meant the correction of irregu- larities of the teeth. State the best method of sterilizing instruments. The best method of sterilizing instruments is to boil them for ten minutes in a \% solution of sodium carbonate. What are the causes of secondary hemorrhage ? 78 ORAL SURGERY. Chief cause, — septic arteritis. Contributory causes : i . Early absorption of ligature. 2. Faulty application of ligature. 3. Liga- ture too near a collateral branch. 4. A diseased condition of the arterial wall. 5. A state of blood unfavorable to repair of any wound (albuminuria or diabetes). 6. Increased blood pressure (plethora, Bright's disease, fever, injudicious excitement, or un- wise administration of stimulants). Define staphylorrhaphy. State the most favor= able age for the operation. By staphylorrhaphy is meant the plastic opera- tion for closing a cleft in the soft palate. The most favorable age for the performance of the operation is between the second and third year. It is very important that staphylorraphy should be performed before the child commences to talk. flention two methods of preserving the aseptic character of a wound. The aseptic method and the antiseptic method. Give etiology and treatment of syncope. Syncope is due to anemia of the brain produced by sudden failure of the heart's action. Lay patient flat on his back with the head low. Make friction over the praecordial region or apply galvanism. Put smelling salts to nostrils and give a little brandy as soon as the patient cau swallow. Give the clinical appearance and treatment of osteoma of the inferior maxilla. ORAL SURGERY. 79 Osteoma of the inferior maxilla may consist either of a general thickening or enlargement of the entire bone or of a local outgrowth. The tumor is ex- tremely hard, grows slowly, and causes no pain un- less it presses upon important sensory nerves. The neighboring lymphatic glands are not enlarged. Treatment. — These tumors are best let alone unless the deformity is great or the movements of the mandible are interfered with. They may be par- tially excised, the offending portions being chiselled, drilled, or ground away, or they may be wholly re- moved by excising a portion of the mandible. Describe suppurative cellulitis. The affected part is hot, tender, and infiltrated ; if superficial, it looks red and angry and is brawny to the touch. Fever is usually present and, in severe cases, one or more rigors may occur. If the part is not incised, the process rapidly spreads throughout the entire extremity or region ; the toxic fever rapidl} T exhausts the patient's strength and the entire sub- cutaneous and intermuscular areolar tissue of the part is destroyed. Define surgical shock. Give the treatment. Surgical shock is the immediate constitutional effect of an injury. Treatment. — When slight, rest in the recumbent posture and the exhibition of some aromatic stimulant (ammonia). If severe, recumbent position with the head low ; surround the patient with hot bottles (well protected) and blankets to maintain and bring up 80 ORAL SURGERY. body-temperature. If conscious and able to swallow, give a little warm tea or stimulant ; if unconscious, a small hot coffee or brandy enema, or a hypodermatic injection of ether or strychnine. Care should be taken not to waste vital pow r er by over-stimulation which will result in excessive reaction. The intra- venous injection of normal saline solution frequently gives excellent results. If the shock is maintained by the presence of a mangled limb, it may be well to perform an amputation. What diseases of the tongue may be mistaken for carcinoma ? , Primary, secondary, or tertiary syphilis, leuko- plakia, chronic glossitis, traumatic ulcers, tubercular ulcers, sarcoma, and actinomycosis. Mention two varieties of cysts of the tongue. Give the treatment of one variety. Dermoid cyst. — Retention cyst, due to the occlu- sion of the duct of a small mucous gland. The retention cyst is best treated by excision. Mention the materials employed for sutures, and describe the twisted or hare=lip suture. Silk, silkworm-gut catgut, kangaroo tendon, sil- ver wire, and horse-hair. The hare-lip or twisted suture consists of metallic pins or needles thrust through both lips of the wound, the edges of which are kept in contact over the pins by figure-of-eight turns of silk. Give the etiology, clinical appearance, and the treatmeut of acute ranula. ORAL SURGERY- 8r Acute ranula is an accumulation of saliva (from obstruction and rupture of Wharton's duct) in a serous sac known as Fleischmann's bursa (Tillaux). Duplay considers the acute ranula to consist of a dilatation of the duct itself. The cystic tumor is situated in the floor of the mouth to one side of the median line. It is globular, semi-transparent, and may attain the size of a ban- tam's egg, pushing the tongue upwards and back- wards and interfering with deglutition and speech. It contains a glairy mucous fluid. Treatment. Excision of a portion of the anterior wall of the cyst and swabbing out the cavity with pure carbolic acid. The cavity is then packed with iodoform gauze and made to heal by granulation. If the condition recurs, the entire growth is to be excised. flention the varieties of displacement in fracture of the inferior maxilla, (live the symptom of treatment of one variety. In fractures through the angle, or lower part of the ramus, there is usually little displacement as the masseter on the outer side and the internal pterygoid on the inner side, maintain the fragments in apposi- tion. When the fracture passes through the neck of the condyle, that process is drawn forward and inward by the external pterygoid, w T hilst the body of the bone is freely movable antero-posteriorly, and is dis- placed toward the fractured side. When the coronoid process is detached it is drawn upwards by the temporal tendon, but no great &? ORAL SURGERY. displacement can occur, owing to the extensive at- tachment of the tendinous fibres. In the most common fracture, through the body of the bone near the mental foramen, the large an- terior fragment is displaced downwards by the mus- cles passing from the hyoid bone to the Jaw. The smaller fragment is drawn upwards by the muscles of mastication and is displaced outwards, so that it over- laps the anterior fragment. In a fracture through the bod}^ of the jaw there will usually be hemorrhage from the mouth, irregu- larity of the denture, crepitus, and a displacement as ' described above. The treatment consists of the re- duction of the displacement, the application of a Bar- ton bandage and the maintenance of an aseptic con- dition of the oral cavit3 r . If necessary, Hammond's splint may be applied. Define neurasthenia and give its symptoms and treatment. A condition of lack of power of the nerve-cen- tres, not dependent upon the existence of organic disease in any portion of trie body. Symptoms. — Loss of weight and slight anemia r excessive irritability of the heart, spots of local ten- derness over the spine, weariness upon exertion r weakness of memory, disturbance of sleep, flushes of heat, profuse sweating, and occasionally disturbances of sensation. Treatment. — Rest, with change of scene and diet; massage, out of door life, avoidance of excitement. ORAL SURGERY. 83 strychnine in fnll doses, and, best of all, the " rest cure" as prescribed by Dr. S. Weir Mitchell. Define odontoma. Give the classification, clinical appearance, and the treatment of odontoma. An odontoma is a tumor originating from some abnormal condition of the teeth or teeth germs. 1. Epithelial odontome. Originates from enamel organs, usually affects lower jaw, forms tumor of great size, and as a rule runs a. perfectly benign course. The only treatment consists in complete removal of the affected portion of the jaw. 2. Follicular odontome (dentigerous cysts), More common in lower jaw, tumor, at first, hard and solid, but subsequently gives egg-shell crackling and even fluctuation. A permanent tooth will be found missing, and there is no history of its having been extracted. The treatment consists in excising a por- tion of the wall of the cyst from the mouth and ex- tracting the misplaced tooth. The interior of the cyst is then to be thoroughly scraped, flushed with an antiseptic solution and packed with gauze. 3. Fibrous odontome. Occurs rarely in rickety children; there is thickening and condensation of the connective tissues around a tooth-sac. Treatment, thorough removal. 4. Radicular odontome. A tumor composed of cement developing at the root of a tooth. It causes severe pain and may result in septic inflammation of the surrounding bone. Treatment, thorough removal. 5. Composite odontome.— These may be very large and resemble osteomata of the antrum. Treatment, ORAL SURGERY. thorough removal if causing trouble. Give the etiology, clinical division, pathologic classification, and the treatment of tumors. Etiology. — Injury or irritation, infection, her- edity, fetal residues. Clinical Division. Benign and Malignant. Pathologic. Classification. I. Mesoblastic or Connective Tissue Tumors. A. Those conforming to the types of fully formed connective tissues ; i. Fibroma,. 2* Lipoma. 3. Chondroma. 4. Osteoma. 5. Myxoma. B. Those conforming to the types of the higher connective tissues : 1. Myoma, 2. Angeioma, 3. Lymphangeioma,, 4. Neuroma.. C. Those conforming to the types of embryonic connective tissue : Sarcoma. II. Epiblastic and hypoblastic tumors,, i. e. y those conforming to the type of Epithelial Tissues: 1. Papilloma,, 2. Adenoma, 3. Carcinoma. III. Tumors composed of Epiblastic, Hypoblas- tic and Mesoblastic Elements,: Teratoma. ORAL SURGERY, 8 5 Treatment. In Benign Tumors, removal if an- noying or if they show a tendency to become malig- nant. In Malignant Tumors, secondary deposits should be removed with the primary growths. If complete removal is impossible they had best be left alone. Give the causes and treatment of spasmodic respiratory failure. Laryngitis, laryngismus stridulus, tetanus, and hydrophobia. Treatment. In tetanus and hydrophobia treat- ment is practically useless. It consists of the admin- istration of chloral between, and of chloroform during .he attacks. In laryngitis and laryngismus stridulus, place child in hot bath. Give syrup of ipecac to produce vomiting and place hot compresses about the throat. If child cannot swallow, tickle throat with finger to produce emesis. Describe the operation of extracting molar teeth, riention accidents that may occur in the extraction of these teeth. First and second upper molars. The operator stands at right of patient, passing the left arm around the head, and holding the lip out of place with the fingers of the left hand. In using the cow-horn forceps, take care to thrust the points of the horn directly into the interspace and then carry the flat blade along the palatine fang as high as possible. A few rocks of the tooth inward and outward combined with a direct force in the line of its long axis will cause it to give way. 86 ORAL S UR GER Y First and second lower molars. Position of operator as before. Use the cow-horn forceps for lower molars, and so apply them that the closnre of the handle forces the points into the interspace where they will meet. If closing the handle does not loosen the tooth, gently rock the forceps inward and ontward nntil the tooth is felt to yield, when it is at once to be lifted from its socket. In extracting the third molar, an appropriate forcep mnst be selected and the traction made in the axis of the single curved root, usually backwards and upwards or downwards, as the case may be. The accidents of extraction are : Laceration of gum, fracture of alveolar process, paralysis ,excessive hemorrhage, loosening or breaking of other teeth, and luxation of the inferior maxilla. Define replantation of teeth, transplantation of teeth, and implantation of teeth. By replantation is meant the return of a tooth to its natural socket after extraction. By transplantation is meant the transference of a tooth from its original socket to one existing in an- other jaw. By implantation is meant making a socket in a jaw where none exists and inserting a tooth into it. Give a differential diagnosis of traumatic ulcer of the tongue and epithelioma of the tongue. The traumatic ulcer is usually situated upon the side of the tongue opposite a mass of tartar, an angle of a tooth, or the edge of a plate. The ulcer is ORAL SURGERY. *7 ragged, irregular, without induration (unless very chronic,) and the lymphatic glands beneath the lower jaw are not enlarged. Epithelioma occurs in middle aged or elderly individuals. The ulcer has a widely indurated base, thick everted edge, an irregular warty surface, a wa- tery discharge, and there is an enlargement of one or more of the submental glands. Give a differential diagnosis of suppuration of the maxillary sinus and tumor of the maxillary sinus. Suppuration. History of preceding alveolar ab- scess or rhinitis. Tumor. No such history. Exophthalmos, encroachment Causes same deformity, but to a upon nasal fossae, a flattening of less degree. roof of mouth, and a projection of the cheek below the malar bone. Intermittent discharge of pus from Nq suppuration . nostril of affected side. Fever. No fever If acute, the cheek is red, hot, and swollen , and the part is painful. Ma ? be P ainf ul 0r P ainless ' Exploratory puncture reveals pus. Exploratory puncture does not reveal pus. It may reveal blood (sarcoma), or exploratory puncture may be impossible, (osteoma.) Give the etiology diagnosis, and treatment of cys- tic dilatation of Steno's duct or of Wharton's duct. Etiology. — A salivary calculus may be formed within Steno's duct and completely occlude its lumen. 88 ORAL SUR GER Y. Diagnosis: Painful swelling in region of parotid gland, pain increased by the ingestion of food. The calculus may be readily detected by probing the duct, or it may be felt through the tissues of the cheek. Treatment. — Remove the calculus by an incision into the overlying buccal mucous membrane. State how syncope spontaneously arrests hemor= rhage. By reducing the force of the blood current and thus permitting coagulation to occur within the wounded vessel. Describe the Hammond wire splint and state in what class of fractures it can be successfully employed. It consists of a firm wire collar or framework which encircles the whole series of teeth in the lower jaw. It is accurately fitted to the jaw and fixed by several wires passing from one half of the jaw to the other, between the teeth. It can be successful^ employed in a fractured mandible where there is much displacement. Define fracture. Give the local and the constitu= tional causes of non=union of fractures. A fracture is a sudden solution of continuity in a bone, usually due to excessive violence. The local causes of non-union are: 1. Faulty apposition. 2. The interposition of fluid, muscular or apone- urotic tissue, or pieces of bone between the ends of the fragments. ORAL SURGERY. 89 3. Want of rest. 4. Defective blood supply. 5. Defective innervation. 6. Inflammation on the surface of the limb. 7. Faulty treatment, and, 8. Local affections of bone (malignant tumors, destruction of the periosteum by inflamma- tion). The constitutional causes are: 1. General constitutional weakness. 2. Osteomalacia 3. Scurvy. 4. Syphilis. 5. Senility (probably). 6. Pregnancy, and 7. The cancerous cachexia. Differentiate sapremia, septicemia and pyemia. Sapremia (septic intoxication) is a wound fever due to the absorption of the products of putrefaction into the system. It is a toxemia or condition due to chemical poisoning, and the blood is not in- fective. Septicemia (septic infection) is a wound fever due to the introduction into the blood and tissues of bac- teria which rapidly multiply. The blood is infective, since it not only contains the toxins but also the organisms which produce them. Pyemia is a wound fever developed during the process of suppuration and is due to the absorption of pyogenic organisms into the circulation. Clinic- go ORAL S UR GER Y. ally, pyemia is septicemia plus metastatic abscesses. State precautions that should be taken when ope= rating on syphilitic patients. Any cracks or abrasions upon the hands of the operator should be protected by a collodion dressing and the hands should be encased in a pair of sterile rubber gloves. At various intervals during the op- eration, the hands should be immersed in an antisep- tic solution and then rinsed in sterile water. At the conclusion of the operation the hands should be well scrubbed, soaked for several minutes in a bichloride of mercury solution (i-iooo), and then washed in ster- ile water. In trifacial neuralgia caused by infection, malaria, grip, what division of the nerve is usually involved ? The first or ophthalmic division. What produces mechanical asphyxia during ether or chloroform anesthesia ? Mechanical asphyxia is produced by the tongue falling back over the glottis. Give the differential diagnosis of fracture and dis= location. Fracture: Dislocation; Preternatural mobility. Immobility. Crepitus. No crepitus. The deformity usually returns The deformity does not usually immediately after it has been cor- recur after jt has beea correcte(L ' rected. Give the anatomic and the clinical varieties of hemorrhage. ORAL SURGERY. 9 i The anatomic varieties of hemorrhage are the arterial, the venous, and the capillary. The clinical varieties of hemorrhage are primary hemorrhage, intermediate or reactionary hemorrhage, and secondary hemorrhage. State why an alveolar abscess may cause suppura- tive inflammation of the maxillary sinus. Because the suppuration is in the floor of the sinus and may point towards its cavity or cause a suppurative inflammation by contiguity of structure. Mention the predisposing and the exciting causes, together with the local and the constitutional symptoms of inflammation. The predisposing causes include everything which lowers the general resistance of the body ; such as Bright's disease, diabetes, anemia, tubercu- losis and chronic alcoholism. • The exciting causes are traumatism, heat, cold, chemical agents, and bacteria. The local symptoms are redness, heat, pain, swelling, and modified function. The constitutional symptom is fever. Give the pathology, symptoms and treatment of inflammation. Pathology.— There are three sets of changes : I. Chauges in the blood vessels and in the cir- culation. The blood vessels dilate. The current is at first more rapid but soon becomes slower, so that an axial stream (red blood corpuscles) and a periaxial 9 2 ORAL SURGERY* stream (white blood corpuscles and blood placques) may be differentiated. In addition to dilating, the vessels become elongated and tortuous. The current finally becomes so sluggish that it moves onward with each systole and backward with each diastole (oscillation). This is followed by stasis. 2. Exudation of serum and transmigration of the leucocytes. 3. Changes in the tissues themselves. These consist of a multiplication of the fixed and wandering connective tissue cells. 1 Symptoms. — The local symptoms are redness, heat, pain, swelling, and modified function. The constitutional symptom is fever. Treatment. — The local treatment includes rest, elevation, the use of heat or cold, local blood-letting, astringents, antiseptics, counter-irritation, compres- sion, and massage. The constitutional treatment comprises good hygiene, a light nutritious diet, purgatives, venesec- tion, antipyretics, hypnotics, analgesics, stimulants and tonics. Give the cause and treatment of noisy movements of the temporo=maxiIlary articulation. Cause. — Laxity of ligaments and weakness of surrounding muscles. In some cases it is due to a displacement of the inter-articular cartilage. Treatment. — Tonics, electricity. The wearing of an occipito-mental sling. If the inter-articular cartilage is displaced an incision may be made into ORAL SURGERY. 93 the joint and the cartilage sutured in its normal position. Define septic intoxication. Give treatment. Septic intoxication is a form of poisoning result- ing from the absorption of the products of putrefac- tion. The local treatment consists of the thorough re- moval of the source of infection and of the antiseptic treatment of the wound. The constitutional treatment must be of a sup- porting character. Alcohol and hypodermatic injec- tions of strychnine are to be recommended. Define stomatitis. Mention the varieties of sto= matitis and give treatment of one variety. By stomatitis is meant an inflammation of the oral mucous membrane. The varieties are catarrhal, aphthous, ulcerative, parasitic, gangrenous, mercurial, syphilitic and scor- butic. Treatment of ulcerative stomatitis: Correct the hygiene. Tonic doses of quinine. Touch ulcers with nitrate of silver. Use as a mouth wash a solu- tion of potassium chlorate or hydrogen peroxide. Differentiate acquired cleft palate and congenital cleft palate. Congenital cleft palate exists at birth and is due to want of union of the two palatal segments of the maxillary processes. 9 4 ORAL S UR GER Y. Acquired cleft palate is produced at some period of extra-uterine life by losses of substance resulting from injury, syphilis, or lupus. How would you treat persistent bleeding after lancing the gums of a child ? By pressure with compresses soaked in peroxide of hydrogen ; by packing the incision with a pledget of cotton saturated with phenate of soda or a solution of tannic acid. In some cases the lips of the wound may be temporarily approximated by a suture. Monsel's salts and solutions are only to be used in extreme cases, since they impair the vitality of the tissues and increase the danger of secondary hemor- rhage. In addition to the local treatment, one of the following hemostatics may be administered : Tr. ergot (gtt. V, repeated in one or two hours), Tr. erigeron canadensis (gtt i, in water every minute until bleeding ceases, or until twenty doses have been taken), gallic acid (gr. i, every two hours). What treatment would you pursue in excessive hemorrhage after tooth extraction ? Remove all clots and pieces of root, plug the tooth-socket with a strip of gauze saturated with per- oxide of hydrogen, and reinforce the plug by means of a supporting pad. Should this fail, a plug may be made of gauze, the meshes of which contain tannic acid or alum. The advantage of the clot formed by tannin is that it is insoluble in the blood. Perchlorid of iron and Monsel's solution should not be employed on account of their injurious effects upon the tissues ORAL SURGERY. 95 and the danger of secondary hemorrhage. In ob- stinate cases, the hemorrhage may always be controlled by packing the tooth-socket with a strip of ganze, in the meshes of which rapidly setting plaster-of-Paris has been incorporated. A pledget of cotton saturated with adrenalin chloride (i-iooo) may also be used. Give one of the causes of antral disease, its diag= nosis, and treatment. An alveolo-dental abscess discharging into the antrum. The diagnosis will be made by the presence of the following signs and symptoms : Pain over the affected region and the discovery of the offending tooth or root. Tenderness upon percussion of the antrum. The escape of pus through the nostril of the affected side. If the antrum contains a considerable quantity of pus, it will be opaque to transmitted light, as compared with the opposite side. The ex- amination is made by taking the patient into a dark room and introducing a small incandescent lamp into the mouth, which is then closed. If the pus can find no outlet, the floor of the orbit will be pushed up, causing exophthalmos, the nasal fossae will be en- croached upon, and there will be edema of the cheek. The treatment consists in the establishment of efficient drainage and the thorough irrigation of the cavity of the antrum. This may be accomplished by extracting the offending tooth or root and enlarging the opening into the antrum. The antrum may also be entered above the root of the second bicuspid p6 ORAL S UR GER Y. tooth, about one inch above the border of the gum. The opening into the antrum must be kept open by a gauze or tubular drain until the discharge entirely ceases. During this time the cavity of the antrum may be irrigated, — at first daily, and subsequently, at longer intervals. How would you treat a case of external fistula with adhesion from an alveolar abscess ? The entire fistulous tract must be dissected out and all cicatricial tissue removed. The necrotic bone must be burred away until healthy bone is reached. After the hemorrhage has been arrested the adjacent skin is to be loosened up and a flap slid over the site of the bone lesion, so that the cutaneous wound shall not directly overlay the wound in the bone. How would you diagnose and treat hypertrophy of the gums, and in what class of persons, as to age and mentality, does it occur? Diagnosis. — Diffuse, spongy bleeding overgrowth of gums. Teeth show that they have been greatly neglected and are covered with ac emulated deposits. The affection occurs after second dentition, usually between the ages of 18 and 25, in those who are ignorant and careless in their personal hygiene. Treatment. — Remove all deposits. Clean teeth. Give antiseptic mouth washes. Instruct in care of mouth, and, if necessary, leech, incise, or excise redundant tissue; or galvano-cautery may be used. ORAL S UR GER Y. 97 How would you treat luxation of the inferior maxilla ? Describe the lesion and treatment anatomi= cally. The mechanism is as follows: When the mouth is opened the condyle slides forward upon the emi- nentia articularis and only a slight traumatism is necessary to displace it still further forward into the zygomatic fossa. The inter-articular cartilage may or may not follow the condyle. The luxation may be unilateral or bilateral, more frequently the latter. The mouth cannot be closed and the lower jaw projects anteriorly beyond its normal position. A hollow may be felt just in front of the tra- gus, in the position normally occupied by the condyle. The condyle may be felt in front of this hollow. If the finger is inserted into the mouth, the coronoid process may be felt in an abnormal position beneath the zygoma. If the dislocation is unilateral, the symptoms are less marked, the jaw is more mobile, and the chin is displaced towards the sound side. Treatment. — All that is needed is to depress the condyle below the level of the eminentia articularis, when the masseter, temporal and internal pterygoid muscles readily draw it back into the glenoid cavity. The patient is to be seated in a chair; the surgeon stands in front of the patient and presses downward upon the molar teeth with his thumbs, which are guarded with a towel. This pressure is continued in a downward and backward direction until the condyle clears the eminentia articularis, when the chin is raised by the fingers. The jaw is then to be kept at g8 ORAL SURGERY* rest for four or five days by a Barton bandage. Give briefly your method of procedure in the treatment of a compound fracture of the inferior maxilla. The niouth, or the external wound, is to be kept as aseptic as possible. Inordinary cases, an external moulded splint may be applied to the chin, and the lower jaw held against the upper one by means of a Barton or of a four-tailed bandage. The fragments may be held in place by a wire collar encircling all of the teeth of the lower jaw. This collar is to be accurately fitted, first to a cast of the jaw and then to the jaw itself, and fixed by sev- eral wires passing from one half to the other, between the teeth. If the teeth are defective, Kingle}^s splint may be employed. This consists of a vulcanite splint fit- ted over the alveolar process. Curved metal bars are attached to the front of the splint and extend back- ward over the cheeks from the angles of the mouth. The splint is kept in position by a bandage passing over the bars and under the chin. This splint will immobilize the fragments, even when the mouth is opened. In obstinate cases the fragments may be wired. Give the diagnosis and treatment of a dentig= erous cyst. Diagnosis: These cysts are usually encountered in young individuals, but may occur in later life. They are far more common in the lower than in the upper jaw. At first the tumor is hard and solid, but ORAL SURGERY. 99 as the bone expands it becomes thinned, and palpa- tion reveals egg-shell crackling or even fluctuation. Upon examination of the denture, one of the teeth will be missing and there will be no history of its ex- traction. Treatment. — Excise a portion of the wall of the cyst (through the mouth) and extract the misplaced tooth. The interior of the cyst should then be scraped, irrigated, and packed with iodoform gauze. How would you diagnose and treat epulic tumors ? Diagnosis. — Benign or fibrous epulis appears as a red, fleshy mass, smooth or lobulated, elastic to the touch and probably showing some superficial ulcera- tion. It is a painless tumor of slow growth. Malignant or myeloid epulis forms a soft, rapidly growing, painful tumor, dusky red in color, and soon ulcerating. Treatment. — The best treatment for fibrous epulis is to remove the growth, together with that portion of the alveolus from which it takes its origin. If neces- sary, a tooth on either side of the tumor, must be extracted, each socket cut through vertically with a saw, and the incisions united below with a chisel. In this manner, a quadrangular piece of the alveolus is removed without interfering with the continuity of the jaw. In malignant epulis, it is necessary to operate as early as possible and to carry the bone incisions quite wide of the margin of the tumor. If the tumor is LofC. ioo ORAL SURGERY. large, it may be necessaiy to remove trie entire thick- ness of the lower, or the palatal segment of the upper jaw, as the case may be. What do you mean by necrosis ? Give its diag= nosis and treatment. By necrosis we mean the death of bone en masse. The diagnosis is made by the presence of a sinus, the history of a preceding inflammation, and the results obtained by probing. Dead bone feels rough and hard ; the probing is not painful, nor is it followed by bleeding. Treatment. — This consists in the thorough re- moval of the dead bone. It may be necessary to chisel or burr through the involucrum and extract the sequestrum. The cavity should be well curetted, irrigated, and packed with iodoform gauze to make it heal up from the bottom. What is a ranula and how would you treat it ? A ranula is a retention cyst, due to the obstruc- tion and dilatation of one of the ducts of the sublin- gual or submaxillary gland. The treatment consists in removing a good-sized piece of the wall of the cyst and swabbing out its cavity with pure carbolic acid. What do you know about aphthae and their treat= ment? The term " aphthae " is an old one and includes aphthous stomatitis, ulcerative stomatitis, thrush, and cancrum oris. ORAL SURGERY. ior Aphthous stomatitis. — Seen in nursing children. Inspection reveals numerous small round vesicles on the cheeks, lips, and tongue ; the vesicles soon break, leaving shallow ulcers with a red areola. Treatment. — Sterilize the milk. Correct any gastric disturbance. Use a mouth wash of boric acid. Ulcerative stomatitis. — Attacks children and adults when in poor health or subjected to bad hygi- enic surroundings. Inspection reveals linear ulcers with gray sloughing bases. The sub-maxillary glands are swollen. In severe cases, loosening of teeth and necrosis of bone may follow. Treatment. — Correct hygiene. Tonic doses of quinine. Touch ulcers with nitrate of silver. Use as a mouth wash a solution of potassium chlorate or hydrogen peroxide. Parasitic stomatitis (thrush). Inspection reveals numerous white elevations, which on removal leave a raw surface. Microscopic examination reveals the saccharomyces albicans. Treatment. — Correct the hygiene. Treat any gastric disturbance. Tonics. Some antiseptic mouth- wash, such as solutions of borax, boric acid, or hydro- gen peroxide. Gangrenous stomatitis (cancrum oris). — Usually seen in debilitated children and after one of the spe- cific fevers, particularly measles and whooping-cough. The cheek is the part affected. Externally, it is swollen, hard, red and glazed ; internally, an irregu- 102 ORAL SURGERY. lar sloughing ulcer is noted. Treatment. — Good hygiene and stimulants. Chlo- roform the child and excise the gangrenous area, cut- ting widely into healthy tissue. The edges of the wound are then cauterized with fuming nitric acid, bromine, or the actual cautery. The resulting de- formity must be treated later by a plastic operation. Describe trismus and how it differs from tetanus. Trismus simply means a spasmodic locking of the jaws. It may have its cause in associated deutal lesions, causing irritation of the nerves of the part; it is also a symptom of tetanus. Tetanus is an acute infectious disease, due to the bacillus of tetanus and characterized by tonic spasms with clonic exacerbations. The spasms also affect the muscles of the trunk. What is a traumatic lesion ? A traumatic lesion is a solution of continuity due to injury. By what surgical operation would you abort an impending alveolar abscess ! Make a slight cut with a sharp scalpel through the soft parts at the apex of the affected tooth. Pierce the outer plate of bone with a spear-pointed drill, thus entering the region in which the suppuration is im- pending. This wound should be kept patulous for several days. How would you diagnose and treat empyema of the antrum ? ORAL SURGERY. ioj Diagnosis: — Pain over the affected region. Ten- derness upon percussion. The escape of pus through the nostril of the affected side. If the antrum con- tains a considerable quantity of pus, it will be opaque to transmitted light, as compared with the opposite side. This examination is made by taking the patient into a dark room and introducing a small in- candescent lamp into the mouth, which is then closed. If the pus can find no outlet, the floor of the orbit will be pushed up, causing exophthalmos, the nasal fossae will be encroached upon and there will be edema of the cheek. The treatment consists in the establish- ment of efficient drainage and in the thorough ir- rigation of the cavity of the antrum. This may be accomplished by extracting the offending tooth or root and enlarging the opening into the antrum. The antrum may also be entered above the root of the second bicuspid tooth, about one inch above the border of the gums with surgical engine so as to remove all shreds of tissue and diseased bone.. The opening into the antrum must be kept open by a gauze or tubular drain until the discharge entirely ceases. During this time the cavity of the antrum may be irrigated, at first, daily, and subsequently, at longer intervals. What are the indications for the use of the lance in deciduous dentition? The lance should never be used until the appear- ance of the white line, which is due to the pressure exerted by the erupting tooth. Lancing should never io4 ORAL S UR GER Y. be performed unless reflex disturbances are produced. What anatomical irregularity of the inferior third molar tooth frequently presents itself in extraction ? An= ticipating this condition, how would you extract it ? The roots of the inferior third molar are almost always fused and curve backward. This throws the tooth against the second molar. Always endeavor to determine the course of the root, and then make traction in a corresponding direction, usually up- wards and backwards. Name some of the forms of sutures emploj'ed in the closing of surgical wounds, and what substances are , used ? The interrupted, the continuous, the mattress, the quilled, and the shotted suture. The materials employed are silk, silkworm-gut, cat-gut, kangaroo tendon, and silver wire. What is torsion, and when is it preferable to other means in arresting arterial hemorrhage ? By torsion is meant the twisting of an artery until its middle and internal coats are lacerated. It is preferable to other means in plastic opera- tions, where it is not considered desirable to leave too many ligatures behind. It is also preferable where aseptic ligatures cannot be obtained. What is the difference between a simple and a compound fracture ? A simple fracture has no communication with the external air. A compound fracture communi- cates with the external air. ORAL SURGERY. 103 When it is surgically necessary to make an inci= sion through a muscle and a choice exists for carrying the incision parallel or transverse to the fibres of the muscle, which way would you adopt, and why ? Make the incision in the direction of the fibres. The reason for this is that fewer fibres will be sev- ered and the function of the muscle will be practi- cally unimpaired. What is a sequestrum ? A sequestrum is a piece of dead bone resulting from necrosis. 1 At what point is the trunk of the facial nerve most liable to injury ? If severed, what change occurs? At its exit from the stylo-mastoid foramen. If severed, a paralysis of the muscles of expression of the affected side is produced. The folds and wrinkles are obliterated upon the paralyzed side. The eyelid cannot be completely closed. On attempting to laugh or show the teeth, the muscles of the non-paralyzed side alone are contracted, and marked asymmetry results from the drawing over of the opposite side. The lips cannot be closed firmly, and whistling is im- possible. Food collects betw r een the cheek and the teeth, owing to the paralysis of the buccinator muscle. What is hare=lip ? Describe a remedial opera- tion and give the best age for its performance. A hare-lip is a congenital fissure of the upper lip, which may extend for a variable distance through the tissues. 106 ORAL S UR GER Y. Rose's Operation. The incision extends from the apex of the cleft, or from within the nostril in a con- centric manner so that a slight angular projection is formed to constitute a prolabium. This is done on each side and, where the nose is much flattened, more tissue is removed from the outer than from the inner side, so that when the parts are sutured together, the nostrils become as nearly as possible symmetrical. By this means, the depth of the lip is increased to allow of subsequent contraction; the vermilion bor- ders must be accurately approximated. Two deep silver-wire sutures should be introduced, one just above the red margin and one close to the nose. Cat-gut sutures are used to bring the margins of the Avound together accurately. The dressing consists of gauze and collodion. The gauze is cut in the shape of a paddle, the broad ends being fastened to the cheek. This should be so applied as to prevent tension upon the wound. The silver-wire sutures are removed upon the fourth day. The best age for the performance of the opera- tion is from 6 weeks to 3 months. Define ankylosis. Give an example. Ankylosis is a condition of partial or complete immobility of a joint, resulting from some preceding inflammation of the articular structures. As an ex- ample might be given that form which is seen in the elbow joint after fractures into the articulation, and the subsequent period of enforced rest. How are fractures classified ? Simple. — Not communicating with the external air. OR A L SUR GER Y 107 Compound. — Communicating with the external air. Comminuted. — A number of small fractures. Complicated. — Associated with a dislocation or with a laceration of the main arterial or nervous trunk. Fractures are also divided into complete and in- complete. According to the line of fracture, they are called longitudinal, transverse, oblique, stellate, etc. Describe several methods for arresting hemor= rhage in general. Ligation. — Make an incision at a slight angle to the line of the artery. Expose the sheath. Make as small an opening in the sheath as possible and pass a ligature about, the vessel by means of an aneurysm needle. Tie the ligature tight enough to lacerate the inner and middle coats. Torsion.— Dissectthe end of the artery free from the sheath for half an inch. Seize it transversely with a hemostatic forceps, and then twist the free end of the artery by means of a second hemostatic forceps until the internal and middle coats are lacerated. Arrest capillary hemorrhage by filling the wound with hot water (125 F.). Give the etiology, clinical appearance, and the treatment of spongy gums. Etiology. — Stomatitis, systemic derangements of any kind from mild fevers to acute diseases, unclean- io8 ORAL SURGERY. liness, calcareous deposits around necks of teeth. Clinical appearance. — The gums appear swollen and flabby around the necks of the teeth. They have a peculiar spongy appearance and their margins are dotted and streaked Math bright red spots and lines. They bleed upon the slightest provocation. Treatment. — Removal of exciting cause, cleanli- ness, local blood-letting, the use of antiseptic mouth- washes, and systemic treatment according to condi- tion of general health. Give the etiology, pathology and treatment of pericemental abscesses. Etiology. — Infection from the root or from a pocket of pus (as in pyorrhea alveolaris). A deposit of uric acid upon the root may irritate the surround- ing tissues and lessen resistance to infection. Pathology. — The same as that of ai^ other abscess. Treatment. — Secure free drainage for pus, render the abscess cavity as aseptic as possible, and prescribe an antiseptic mouth wash. Give the etiology, clinical appearance, and treat= ment of arsenic necrosis of the alveolar process. Etiology. — The arsenic usually gains -access to the alveolus from an application made to the pulp. Clinical appearance. — A red tumefied area in the centre of which a slough is located. The process generally extends down into the alveolus and affects the septa between the teeth. ORAL SURGERY. io 9 Treatment. — Removal of necrotic tissue. The local application of sesqni-oxide of iron has been highly recommended. Repeated syringings and an- tiseptic month washes. Give the method of removing a broken bur or nerve broach from a pulp canal. Drill aronnd the bnr with a fine fissnre drill ; iodine may be applied and the part rnsted ont ; sul- phuric acid may be used to remove some of the tooth structure, or an attempt may be made to draw out the bur with a barbed Donaldson's broach. Give the causes, pathologic conditions and the symptoms of traumatic dislocation. Causes. — The application of external violence and muscular force, acting alone or in combination. Pathologic conditions. --The ligaments are par- tially or completely torn. In closely fitting joints (particularly hinge-joints), the bony surfaces are fre- quently fractured. The cartilages may be bruised or partially detached and the neighboring muscles and tendons lacerated or displaced. Surrounding vessels and nerves are frequently injured and the area in- volved is always infiltrated by a considerable effusion of blood. Symptoms.— Pain, bruising and swelling of the soft tissues. Deformity, since the articular end of the bone is displaced into a new position where it may often be felt and sometimes seen. Restricted mobility of the affected joint. True crepitus is not present unless a fracture co-exists. no ORAL SURGERY. Give the diagnosis, prognosis, and treatment of moist gangrene of the pulp. Diagnosis.— If there is an outlet for the escape of the gases of decomposition, pain is not necessarily experienced. Ordinarily, however, the condition causes more or less intense pain, which is usually of a throbbing and heavy character. If inflammation has spread to the surrounding tissues, the application of heat may cause an increased amount of pain. A foul smelling odor is constantly present. Prognosis. --Not necessarily bad. The tooth may be saved in a majority of cases. Treatment.— Removal of all decomposed parts and products, disinfection of pulp canal, hermetical sealing of apex of the tooth, and filling of the pulp canal. Give the etiology, diagnosis, and treatment of acute nonpurulent marginal gingivitis. Etiology.— Mechanical or thermal irritants (such as rough edges of an overhanging filling), rough treatment in excavating or filling a cavity, overheat- ing while drying a cavity, friction while excavating with bur, or cutting down of fillings with sand-paper discs, careless use of ligatures (particularly when they are left upon the tooth for some time), the use of some strong caustics, or other drugs. Diagnosis.— Severe pain, usually of a throbbing character and other local signs of inflammation. The tooth is slightly loose, and protrudes somewhat from its socket. ORAL SURGERY. in Treatment.— Removal of cause, local blood-let- ting, paint parts affected with iodine. Give the clinical appearance and the treatment of syphilitic interstitial gingivitis. Inflammation, attended with superficial ulcera- tion of mucous membrane and general oozing of a grayish-white color. Treatment.— Iodides internally. Antiseptic mouth- washes locally. Describe the "direct method" of producing arti- cial respiration, In the direct method, the air is warmed and pumped into the lungs. The apparatus required is a pair of bellows, a face mask, and intubation tubes (in case the mask does not suffice). There should be a metal tube, with an opening in it, set in the rubber tubing, so that the operator can allow the escape of any excess of air blown by the bellows. If the mask is used a ligature should be passed through the tongue so that it may be readily held forward. If the air cannot enter the lung, intubation is to be per- formed, and there will be no difficulty. A respiratory rate of 16 to 20 a minute should be maintained. If'there is no apparatus for warming the air, the temperature of the room must be raised to at least 85 ° F. Give the etiology, pathology, symptoms, and treat- ment of hyperemia of the pulp. Etiology. — Irritation of bacteria, lactic acid, 1 12 ORAL SURGERY. traumatism, exposure, denudation of root, and irrita- tion from a filling. Pathology. — Practically that of a beginning in- flammation. When cut into, it bleeds, rathei freely. Symptoms. — Pain, increased by percussion, or by the application of either hot or cold substances. Treatment. — Local and general sedatives. Coun- ter-irritation. If pulp does not respond, local blood letting. As a last resort the pulp may be destroyed. What precautionary measures should be observed in the ligation of arteries ? Asepsis, avoid wounding important surrounding structures, make as small an opening as possible in the sheath, never tie near a collateral branch (or if forced to do so, tie branch also), and be sure that the ligature damages the inner and middle coats suffici- ently to insure the obliteration of the vessel at that point. Give the treatment of septic wounds. Cleanse the wound as thoroughly as possible, syringe with hydrogen peroxide, and irrigate with bi- chloride (i-iooo). If the septic condition of the wound is marked, solutions of chloride of zinc should be ap- plied to all of its recesses. If the wound is large and irregular, rubber drainage tubes should be introduced into the most dependent positions. If the wound is small, gauze drainage may suffice. The best dress- ing is one of wet bichloride gauze. The constitu- tional treatment should be of a supporting character. Give the etiology, symptoms, and treatment of OR A L SURGER Y. iij acute periostitis of the inferior maxilla. Etiology. — Traumatism, extension from a conti- guous inflammation (such as an alveolar abscess), the exanthemata (particularly measles and scarlet fever) . It may also be caused by general conditions, such as rheumatism, gout, or pyemia. Symptoms.— The ordinary phenomena of acute inflammation. The pain is of an intense aching character, worse at night, and increased by pressure. If the outer surface is involved, and the process go on to suppuration, a brawny swelling develops which softens in the center, the overlying skin becoming reddened and edematous. When the abscess is opened, bare bone is felt, and the greater portion of the de- nuded structure dies. Treatment.— Rest, leeches, and fomentations lo- cally, if seen early. A good purge should be given, and any underlying diathesis treated. If suppuration is threatened, a free incision should be made down to the bone. If necrosis has occurred, the parts must be dressed antiseptically, until the sequestrum is de- tached. If the sinus opens internally, antiseptic mouth- washes. Give the etiology and treatment of epistaxis. Etiology.— Traumatism, ulcers or tumors of the nasal septum, rupture of varicose veins in mucous niembrame of septum, cerebral congestion, hemo- philia, purpura, scurvy. Treatment.— In the majority of cases there is a local cause. If the bleeding point is detected, it should be touched with a pointed galvano-cautery or ii4 ORAL SURGERY. with a swab saturated with a solution of chromic acid. Cold may be applied to the root of the nose and to the nape of the neck. If the bleeding point cannot be located, the anterior nares should be packed with strips of aseptic gauze saturated with hydrogen per- oxide. If the hemorrhage still continues and the blood drips into the nasopharynx, the posterior nares must be plugged with the aid of Bellocq's sound or a rubber catheter. Describe the necessary preparation of patients for general anesthesia by ether or chloroform. State what remedies and instruments should be at hand. The patient should be examined as carefully as though he were an applicant for life insurance, and all organic diseases should be excluded. This in- cludes physical examination of the lungs, heart, ab- domen, etc. and chemical and microscopical examin- ation of the urine. The night before the anesthesia, the patient should receive a half ounce of Epsom salts, and on the morning of the operation, the lower bowel should be emptied by enema. Just before the anesthesia all loose bodies, false teeth, etc., should be removed from the mouth. No food should be taken for at least six hours before the anesthesia. Instruments and remedies. --Sterile hypodermatic syringe and sterile solutions of atropine sulphate, strychnine sulphate, nitro-glycerine. Brand}', ammo- nia, tongue forceps, and mouth gag. Tracheotomy in struments, a battery, and an apparatus for forced arti- ficial respiration should always be within reach in a hospital. ORAL SURGERY. u 5 Give the treatment of wounds of the tongue. Arrest hemorrhage by exposure to the air, ice, hot water or ligation. If wound is small, sutures are not required. If large, deep seated sutures should be introduced and the ends tied with more than ordinary care, since the motions of the tongue are apt to loosen the suture. An antiseptic mouth-wash should be prescribed. Define scarification. Give the method of this ope= ration and state the results obtained, mention the nec= essary precautions to be observed in scarification. By scarification is meant the operation of mak- ing numerous small superficial incisions. The incisions should be parallel, arranged in the form of a lozenge and go through the skin and superficial fascia. The results obtained are bleeding and the re- lief tension. The necessary precautions to be observed are the details of rigid asepsis. Mention three tumors of antrum. Give treat= ment. Osteoma, sarcoma, and carcinoma. Treatment.— The osteoma requires no treatment unless it presses upon important structures, or causes great deformity, when the offending portions of the tumor may be removed. Before such a partial opera- ation is done, however, malignancy must be absolutely n6 ORAL SURGERY. excluded. If a sarcoma or carcinoma can be thor- oughly removed by an excision of the superior max- illa, this operation is indicated. If the malignant growth can not be thoroughly removed, the toxins of erysipe- las may be injected. Give the local treatment of hemorrhage. Exposure to air, cold, hot water, position (usually elevation), direct presure, styptics, cauterization, acu- pressure, forcipressure, torsion, and ligation. Give treatment of injuries of the mouth caused by carbolic acid. Apply alcohol as quickly as possible to dissolve excess of carbolic acid. An antiseptic mouth-wash should then be used. Give the diagnosis and treatment of papiilomata of the gums. Diagnosis. — It is an innocent epithelial tumor consisting of a fibrous stroma which contains blood- vessels, lymphatics, and an epithelial covering peculiar to the part from which it springs. The tumors are generally multiple, warty-like growths, usually soft and seen upon the mucous membrane. The}' do not, as a rule, give pain, and are either smooth, rounded or of cauliflower shape. They are generally very vascu- lar and bleed quite freely. Treatmant— Immediate and thorough removal since they show a most pronounced tendency to become malignant. Describe the technic of ligation of arteries. Thoroughly asepticize the part. Make an in- cision over the line of the artery. It is best to make ORAL SURGERY. ny this incision at an angle of five degrees to the line of the vessel. Divide the structures layer by layer, avoiding important vessels and nerves. After dividing skin, superficial and deep fascia, the pulsations of the vessel should be sought for. When the sheath of the vessel is reached, it should be opened as far away from the vein as possible (example, open carotid sheath upon inner side). This opening in sheath should be just large enough to allow room for the aneurism needle. In passing the aneurism needle always go from the most difficult to the least difficult side, and never lift the artery up from its bed to a greater extent than is absolutely essential. Before tying the ligature, be sure that it controls the circulation. In tying the ligature exert an equal amount of force upon both ends. After the vessel is ligated, the cutaneous wound is sutured and an aseptic dressing is applied. Give the differential diagnosis of ozaena and em= pyema of the antrum. In ozaena, the offensive discharge proceeds from both nostrils, and the nasal mucous membrane is atrophic. The maxillary sinuses transmit light when the patient is in a dark room with an incandescent lamp in the mouth. There is an absence of any inflammatory symptoms in the tissues overlying the antrum. In empyema of the antrum, the discharge pro- ceeds from the nostrils of the affected side; the nasal mucous membrane upon the oppsite side may be nor- mal; and the diseased maxillary sinus is more opaque n8 ORAL SURGERY. to transmitted light than is the normal antrum. There are inflammatory symptoms in the tissues over- lying the antrum. The cause of the empyema (such as an alveolar abscess) may be found. Give the diagnosis and clinical appearance of mye= loid sarcoma. Myeloid sarcoma always grows from bone. It affects the long bones (particularly the upper end of humerus and tibia, lower end of femur). It most commonly affects individuals between 10 and 40 years of age, but it may occur in old age. The tumor is one of rather slow growth; it may pulsate, fluctuate in certain portions of its extent, or give rise to egg- shell crackling. Give treatment of fracture of superior maxilla. State the complications that may arise. Correct any displacement; as a rule, all the' treat- ment required is to keep the patient quiet and apply cooling lotions to the part. The patient should be fed through a tube if the palatal process is involved. A dental plate should be applied to a broken alveolus. The complications that may arise are severe hemorrhage, suppuration (empyema of antrum) and necrosis. Give the clinical appearance, the symptoms and treatment of necrosis caused by an impacted wisdom tooth. The gums are usually discolored, slight bleed- ing is common, pus exudes from numerous openings over affected area. Pain may or may not be present. If the condition is allowed to persist the general health is impaired. ORAL SURGERY. u 9 Treatment. --Remove cause by extracting the malplaced tooth. ; antiseptic mouth-washes should be freely employed. The necrosed portions of the al- veolus should be freely removed. Give the diagnosis and treatment of fracture of the inferior maxilla. Crepitus may be obtained. The condyle is usually drawn forwards and inwards by the external pterygoid, while the body of the bone is freely mov- able antero-posteriorly, and is displaced toward the fractured side. Treatment.— Barton's bandage. Owing to the difficulty of fixing the upper fragment, it is likely that wiring would be the best procedure. (live the symptoms of trifacial neuralgia, when the second division is affected. Spasmodic attacks of pain in the teeth of the upper jaw, in the upper jaw itself, in the lower lid, in the side of the nose, and in the upper lip. Differentiate neuritis and neuralgia. By neuritis is meant the inflammation of a nerve. By neuralgia is meant severe paroxysmal pain along the course of a nerve, and not associated with demonstrable structural changes in the nerve. The pain of neuritis is increased by pressure ; the pain of neuralgia is frequently relieved by pres- sure. A differential diagnosis is sometimes impos- sible. i2o ORAL S UR GER Y. Give the etiology and clinical features of epithe= lioma of the lip. Etiology. — It is commonly stated that this tumor is due to the irritation produced by smoking a short clay pipe, which is allowed to rest on one or the other side of the lip near the angle. It may also originate opposite a projecting rough or carious tooth. Pathology.— The affection may be a typical ma- lignant ulcer, a wart-like growth subsequently be- coming fungous and ulcerated, or a chronic infiltration leading to an irregular nodular thickening. Sections of the growth show an abundance of " epithelial pearls." Clinical features.-- Almost always affect lower lip. Rarely met with in women (i in 20). Occurs past middle life. Submental and sub-maxillary glands not implicated for three or four months. Sore de- velops slowly. Sharp burning or lancinating pains. Odor often extremely offensive. Why should the hands be disinfected before a sur= gical operation ? Describe the method used. Because the epidermis always contains patho- genic bacteria. Furbringer's method.— Hands and forearms are scrubbed continuously for five minutes with soap and aseptic nail-brush. The nails should be thoroughly cleaned and trimmed short. The hands are then plunged into absolute alcohol for at least one minute, and then are plunged while wet into a hot sublimate solution (1-1000) and thorough!}' scrubbed ORAL SURGERY. 121 with a nail-brush for at least one minute, particular attention being directed to the nails. A better method is that of Kelly :— The hands and forearms are cleansed as before with soap and water and the nails cleaned and pared. The hands and forearms are then immersed in a saturated solu- tion of potassium permanganate until they are stained a deep mahogany red, or almost black. They are then immersed in a saturated solution of oxalic acid until they are completely decolorized. The oxalic acid is then washed off in sterile water. Describe the methods used in plastic surgery. Displacement.— Stretching or sliding of tissues. 1. Simple approximation after freshening the edges. 2. Sliding into position after transferring tension to adjoining localities. Interpolation— Borrowing material from adjacent regions, from a limb or from another person. 1. Trans- ferring a flap with a pedicle. 2. Transplanting with- out a pedicle. Retrenchment.— Removing redundant material and causing cicatricial contraction. Describe local anesthesia. State the precaution necessary in producing it. Local anesthesia is best effected by the use of cocaine, and may be employed with safety when the cocaine can be confined to a limited area. The part, say a finger, is asepticized and a stout ligature or fillet placed about its base. The cocaine is then in- jected between the layers of the skin and also in the J 22 ORAL S UR GBR Y. vicinity of the digital nerves. The entire finger will be anesthetized within three or five minutes. Precautions —Asepsis—Never risk the absorption of. an amount of cocaine which exceeds the normal dose At the conclusion of the operation, loosen the ligature and then tighten it again after five or ten seconds. Repeat at intervals so that the cocaine in the tissues will not all be absorbed at one time. Give the clinical appearance of squamous lesions of syphilis in the mouth. The epithelium is whitish and opaline resembling a surface that has been touched by nitrate of silver. If eroded, the surface is red and smooth after the superficial epithelium has desquamated. The patch is always circular or regularly oval and the derma is thickened upon its surface. Give the treatment of localized stomatitis. Antiseptic mouth-washes, swabbing with a weak solution of nitrate of silver, the removal of any local irritant (such as a carious tooth), and the adminis- tration of tonics. Give a differential diagnosis of an abscess, a cyst, and a fatty tumor. An abscess is characterized by redness, heat, pain, swelling, fever, fluctuation, pointing, and the hypodermatic needle reveals pus. A cyst is characterized by an absence of inflam- matory symptoms, unless it is inflamed. Fluctua- tion is present and the hypodermatic needle reveals a non-purulent fluid. A superficial cyst can be better outlined than is the case with an abscess. ORAL SURGERY. 123 A fatty tumor is inelastic and doughy to the touch. It is adherent to the skin and, when it is moved, causes a dimpling of the overlying integu- ment. There is an absence of inflammatory symp- toms. State a method of sterilizing sponges. The sponges should be placed in a muslin bag and well pounded to remove all particles of sand and other foreign materials. They are then rinsed out m water several times. A very good way is to place them in a basin, or pail, and allow the water to run in upon them from a tap for several hours. They are next soaked in a saturated solution of permanganate of potassium, are afterwards decolorized in a solution of j oxalic or of sulphuric acid, and are then left for twenty-four hours in an aqueous solution of hydro- chloric acid, made strong enough to taste slightly sour. After this, they are again soaked in water un- til the washings are clear. They are next placed in a bichloride solution (1-500) for twelve hours, and finally are rinsed in warm water and preserved in cov- ered glass jars containing a three per cent aqueous solution of carbolic acid, the solution being changed every week. What class of patients should not be anesthetized by (a )nitroiis oxide, (b ) chloroform, (c) ether? (a) Those with diseased blood vessels. Those in whom complete muscular relaxation is desired. (b) Those with myocardial disease. (c) Those with bronchitis or Bright's disease. 124 ORAL SURGERY. Give reason for removing a blood clot from the surface of a wound. The chief reason for removing a clot is that it is capable of forming a most excellent culture medium for the growth of bacteria. Its presence consequently favors the development of sepsis. If the clot is not removed by the surgeon, it will be removed by nature, since it is nothing more nor less than a foreign body. Give the etiology and treatment of erosion. Etiology. — Acids attacking the necks of the teeth. The acid may proceed from the buccal glands or be regurgitated from the stomach. Treatment. — Applications of milk of magnesia, chalk, or some such alkaline substance. Correct any digestive defect and destroy the glands by the cau- tery, if they can be definitely located. The eroded places should be filled. Give the method of operation for exposing the in- ferior dental nerve. Incision, two inches in length, along the lower bor- der of the jaw, beginning slightly behind the angle and well under the border. The upper edge of the wound is displaced upward over the ramus, the masseter muscle is separated from the bone with .a periosteal elevator, and a ^ inch trephine applied one inch and a quar- ter above the angle. This exposes the nerve at its entrance into the inferior dental foramen. The nerve may be brought to the surface b} T a small hook or, the incision may be prolonged above and parallel to the edge of the jaw and the canal for the nerve laid open all the way to the mental foramen. ORAL SURGE R Y. 125 What dangers may result from punctured wounds ? Give treatment. The greatest danger is sepsis. Another is te- tanus. A lesser danger is injury of deep structures. Treatment. — Secure efficient drainage and pack the wound so as to make it heal up from the bottom. Infection with tetanus should be guarded against by opening up all parts of the wound so that the oxygen of the air may gain free access. Describe Barton's bandage. The roller should be two inches in width and six yards in length. The initial extremity of the roller is placed on the head just behind the mastoid process. The bandage is then carried under the oc- cipital protuberance, obliquely upward, under and in front of the parietal eminence, across the vertex of the skull, then downward over the zygomatic arch, under the chin, thence upward over the opposite zygomatic arch and over the top of the head, crossing the first turn as nearly as possible in the median line, and thence carrying the turns of the roller under the parietal eminence to the point of commencement. The bandage is then passed obliquely around under the occipital protuberance and forward under the ear to the front of the chin, thence back to the point from which the roller started. These figure of eight turns over the head and the circular turns from the occiput to the chin should be repeated, each turn exactly overlapping the preceding one until the band- age is exhausted. Differentiate an ulcer and a fistula. 126 ORAL SURGERY. An ulcer is a?* solution of continuity of the skin or mucous membrane due to molecular death of the part. , ,;■ A fistula is a suppurating tract connecting a cutaneous or mucous surface with a normal cavity of the body, or connecting two normal cavities. Strictly speaking a fistula always has two openings. Give the (Jiganosis of ulcerating gumma of the oral cavity. r Preceding history, of ..syphilitic infection' and the presence of an inflammatory swelling, the surface of which is ulcerated. The ulcer is deeply excavated, the edge is undermined, the surrpiinding tissues are hyperemic, and there is a tough ( or soft tenacious slouefh adherent to its base. There is no glandular involvement, as a rule ; the sore will heal under spe- cific treatment and leave a depressed scar or a per- foration. .., Give the differential diagnosis between malignant and non=nialignant tumors of the upper jaw. Malignant tumors grow rapidly, give metastasis, are painful, recur after, removal, may ulcerate, and finally cause death. .,, :, u ., , Non-malignant tumors, grow slowly, do not give metastasis^are not painful; (except, by pressure), do not recur after removal, rarely ulcerate, and -do, not cause^ death (except mechanically). The malignant tumors of the upper jaw are of t more: frequent occur- rence than are. the benign. »• \ cr" Give direction for diagnosis of mercurial sto= matitis. ORAL SURGERY. 127 The diagnosis is made by observing the follow- ing points : The individual may work in mercury or have been taking the drug internally. There will be tenderness of the gums, manifested by bringing the teeth forcibly together, redness of the gums near the insertion of the teeth, a metallic taste, profuse salivation, fetor of breath, the tongue may be red- dened, swollen, and ulcerated, and protrude from the mouth. In severe cases, ulceration of the mucous membrane, loss of teeth, and necrosis of the jaw may result. Describe a four=tailed bandage. This bandage is prepared by taking a portion of a roller bandage,three inches wide and one yard in length, and splitting each extremity up to within two inches of the centre. The undivided portion of the bandage is placed upon the point of the chin. The two lower tails are then drawn up and tied over the vortex while the two upper tails are secured behind the occiput and then, to prevent slipping, these ends are knotted to the ends of the former. What precaution should be taken in extracting molars and bicuspids of the inferior maxilla ? The usual antiseptic precautions, such as sterili- zation of instruments, and cleansing of parts by germicidal solutions. The selection of a proper forcep, the history as to previous extraction, whether difficult or a tendency to hemophilia, and above all, keep in mind the fact that fracture may occur either in the body or in the alveolar process if violence is 128 ORAL S UR GER Y. used. The jaw may also be dislocated. The proper motion for loosening root attachments should be ap- plied and some guard placed over the upper teeth to prevent breaking them. Be prepared to treat shock and hemorrhage. Give the pathology and treatment of epithelioma. Pathology. — Squamous epithelioma are nodular or wart-like elevations of the skin or mucous mem- branes tending to superficial ulceration. The microscope reveals branching columns of epithelial cells extending from the papillae of the skin into the deeper structures. "Cell-nests" are frequent. In-' volvement of the lymphatic glands is less marked than in the remaining forms of carcinoma. Cylindric epithelioma. — Found in gastrointesti- nal tract and in uterus. They are composed of acinus-like tubular structures, frequently composed of a number of layers of epithelium, the outer layer often being distinctly columnar. Later on, the acini become filled with epithelial cells of various shapes and the cylindric character is lost. They more nearly resemble the glandular cancers in their general characteristics than does the squamous variety. Treatment. — Thorough excision of the involved tissue wherever found. If a squamous epithelioma is local beyond doubt, and there be no lymphatic in- volvement (as in xodent ulcer), the growth may be destroyed by Michel's or Bougard's paste. Describe palliative treatment of malignant tumors of the mouth. ORAL S UR GER F. i2 9 The palliative treatment of malignant tumors of the mouth consists in keeping the buccal cavity as aseptic as possible by means of antiseptic mouth- washes. Local anesthetics (cocaine, menthol) are employed. Morphine is administered and, in some cases, it has been advised to divide the lingual nerve. If the case is one of sarcoma, Coley's fluid may be tried. The X-ray is a recent addition. Give the treatment of a case of non-union in frac= ture of the inferior maxilla. Make incision along lower border of body of jaw, expose fragments, remove any intervening tissue, freshen edges, and wire together. In some cases it may suffice to rub the ends of the fragments together and then apply a Hammond splint. Give treatment of a lacerated wound. If the wound can be thoroughly cleansed and the edges have not been markedly contused, such a wound should be sutured and a wet bichloride dress- ing applied. If the wound cannot be thoroughly cleansed or if the edges are contused, clean the wound as thoroughly as possible, irrigate with a bi- chloride solution (1-2000), and apply warm antiseptic fomentations until all sloughs have separated. The wound should then be treated like any granulating surface. What is arthritis ? Give treatment. By arthritis is meant an inflammation of a joint which involves all the structures of which it is com- posed. i jo ORAL SURGERY. Treatment of Acute Arthritis. —In early stage, elevate the limb, immobilize absolutely, and put in such position that, if ankylosis occurs, the part will be of some use to the patient. Fomentations or an ice-bag may also be applied. As soon as symptoms of approaching suppuration appear, open joint freely in one (or better two) places, and wash out with some sterile or antiseptic solution (normal saline solution or sublimate 1-8000). Maintain fixation, continue irrigation until all symptoms of inflammation have disappeared, and look after the general health, If ankylosis occurs in a faulty position, resection of the joint may be required. How would you arrest hemorrhage from the tongue ? Hemorrhage from the tongue may be arrested by exposure to the air, by ice, by hot water, by liga- tion, by suture, and by the cautery. Give the differential diagnosis between fracture of the neck of the inferior maxilla and dislocation of the temporo=maxillary articulation. In the fracture of the neck of the condyle, there may be crepitus, the condyle is drawn forwards and and inwards by the external pterygoid muscle, the body of the bone is freely movable, and the chin is displaced toward the fractured side. In a unilateral dislocation there is limited mo- tion of the jaw, no crepitus, and the chin is displaced toward the sound side. If the dislocation be bilateral, the mouth cannot be closed, the lower jaw projects forward, and there is a hollow upon both sides in front of the tragus. ORAL S UR GER Y. iji Give etiology and treatment of false ankylosis. Etiology. — Inflammation outside of the joint, disuse. Treatment. — Where inflammation has been cured, massage and passive motion, the alternate hot and cold douche, and graduated exercise. If due to disuse,, exercise, massage and galvanism. Define neuritis. Give cause and treatment. By neuritis is meant the inflammation of a nerve. Causes. — Inflammation, exposure to cold, some abnormal condition of the blood induced by rheuma- tism, chronic alcholism, diabetes, etc. Treatment. — Keep part at rest. Apply blisters along the course of the nerve. The administration of small doses of bichloride of mercury is sometimes of benefit. Treat anv local cause or constitutional dyscrasia. It may be necessary to control pain by hypodermatic injections of morphine. When should a sequestrum be removed ? A sequestrum should be removed as soon as it has separated. If the sequestrum is central (as in inferior maxilla), it should be left until the involucrum becomes sufficiently strong, the case meanwhile receiving ap- propriate antiseptic treatment. In such an instance, etc., the sequestrum acts as a splint. Define asphyxia. Give treatment. Asphyxia is suffocation. The suspension of vital phenomena which results when the lungs are deprived of oxygen. Treatment. — Remove any local cause. If im- 132 ORAL S UR GER Y. possible to remove cause (in the larnyx for example) y quickly perform tracheotomy below obstruction. After obstruction is removed or circumvented, artificial respiration is always indicated. If no local obstruc- tion, artificial respiration from beginning; strychnine, atropine or probably cocaine should be given by an assistant while the operator is performing artificial respiration. How should chloroform be administered ? Ether? What accidents may occur ? Give treatment. Chloroform should be administered in free admix- ture with air (chloroform vapor 5%, air 95%). Ether should also be administered by the open method (ether vapor 95%, air 5%). Accidents. — Death from cardiac or respiratory paralysis, mechanical asphyxia, congestion of brain, or by the entrance of vomited material into the larnyx. Treatment. — Failure of respiration is treated by withdrawal of anesthetic, clearing out throat and pulling f 01 ward of tongue, the performance of artificial respiration, the exhibition of pungent aromatics (ammo- nia), the hypodermatic injection of strychnine, atro- pine, or cocaine, the alternate douche of hot and cold water, and the use of the ^electric brush." Failure of circulation. — Withdraw the anesthe- tic, invert the patient, give hypodermatic injections of whiskey and strychnine, and perform artificial respi- ration, clearing out the mouth and holding the tongue forward. Describe the operation for removing calculi from the salivary duct. The calculus is located by means of a probe and the palpating finger; the duct is incised and the cal- ORAL SURGERY- jjj cuius removed. If the calculus is situated in the sub- stance of the submaxillary gland, total removal of the gland may be necessary. In some cases the calculus may be seen projecting from the main duct of a gland, in which case it may be removed without in- cision. How are the wounds of arteries classified ? Incised, lacerated, contused, punctured, poisoned, and gun-shot. They are sometimes divided into those in which the artery is completely divided and into those in which the artery is only partially divided. What is the difference between a traumatic and a congenital dislocation ? A traumatic dislocation is one produced by the application of external violence and muscular force, acting alone or in combination. A congenital dislocation is a malformation of a joint which exists at birth. Describe Gibson's bandage. The roller should be two inches in width and six yards in length. The initial extremity of the roller should be placed upon the vertex of the skull in a line with the anterior portion of the ear; the bandage is then carried downward in front of the ear to the chin, passed under the chin, and carried upward on the same line until it reaches the point of starting. The same turns are repeated until three complete turns have been made. The bandage is then con- tinued until it reaches a point just above the ear, ij4 ORAL SURGERY- where it is reversed, .carried backward around the oc- ciput, and continued around the head and forehead until it reaches its point of origin; these circular turns are continued until three .turns have been made. When the bandage reaches the occiput, having com- pleted the third turn, it is allowed to drop down to the base of the skull, and it is then carried forward below the ear and.across the chin, being brought back upon the opposite side of the head and neck to the point of origin; these turns are repeated until three complete turns have beeir made, and upon the com- pletion of the third turn, y the bandage is reversed and carried forward over the occiput and vertex to the forehead, and its extremity is here secured with a pin. Pins should also be applied at the points where the turns" of the bandage cross each other. ... , Give the etiology and the treatment of tetanus. Etiology. — The infection of a wound with the bacillus tetani. 'It -is more common in hot climates, in dark-skinned races, and in those who are employed about stables. Hygienic 'errors favor development, particularly, the .overcrowding of sick and wounded in a limited space. ..': n .« .■ '1 . j.< , •. Treatment. — Preventive treatment consists of ap- plying the principles of antisepsis, to every wound en- countered. M ■--* Gj |v Local treatment. — Antiseptic treatment of wound. Symptomatic treatment. — Chloroform during the exacerbations of the spasm and chloral between the exacerbations. The introduction of food into the stomach by stomach tube, and the evacuation of the ORAL SURGERY. T 35 rectum and bladder at regular intervals. Calabar bean has been highly recommended. Specific treatment. — The administration of the anti-toxin, which is best done by trephining and in- troducing it beneath the dura mater. The results ob- tained in man are anything but promising. What is pyorrhea alveolaris ? Give the etiology and treatment. Pyorrhea alveolaris is an inflammatory condition of the margins of the gums, accompanied by a muco- purulent discharge, which arises from pockets or pouches extending for a greater or less distance along the roots of the teeth. Etiology. — Gout, uric acid, diabetes, certain con- ditions of diet and irregularities of the teeth might be mentioned as predisposing factors. It is always preceded by an excessive deposit of tartar, beneath which bacterial infection occurs. Treatment. — Removal of tartar and application of astringents and antiseptics, preferably peroxide of hydrogen. These applications must be made to all parts of the pouches or pockets. Sulphuric acid has been recently recommended. The treatment is prolonged and tedious. In many cases the teeth have been sacrificed. Define a cyst Hention three divisions of cysts and give the etiology and treatment of one division. By a cyst is meant a more or less rounded cavity with a distinct lining membrane, distended with some fluid or semi-solid material. I. Cysts formed by the distension of pre-exist- ing spaces. ij6 ORAL SURGERY. 2. Cysts of embryonic origin. 3. Cysts of new formation. Etiology. — Dermoids may be due to the persis- tence of epithelial cells, in the deeper tissues, in situ- ations where fleshly segments coalesce during fetal life. They may also be due to the persistence of cer- tain tubular canals (thyro-glossal duct, post-anal gUt) ' Cysts of embryonic origin (dermoids) are to be removed by careful dissection. What are aseptic wounds ? Describe an aseptic wound. Aseptic wounds include all which are preserved from contamination by poisonous bacterial products, whether such poison come in contact with the wound directly or be generated in it by the action of germs that gain access to it. In an aseptic wound the process of healing is un- disturbed, union occurs by first intention, there is no suppuration and no visible sign of inflammation. Give treatment of an acquired cleft palate. If the aperture is small, the local disease cured, and the general health good, an attempt may be made to close the perforation by stripping up muco-perios- teal flaps, paring the edges and suturing them to- gether. In the great majority of cases, however, the best treatment consists of the introduction of an ap- propriate obturator or artificial velum. How should a penetrating wound of the temporo= maxillary articulation be treated ? If the wound is small and there is reason to be- ORAL SURGERY. i 3 y lieve that it was made by an aseptic instrument, the skin should be thoroughly cleansed and an antiseptic dressing applied. A careful watch is then kept upon the condition of the joint and the temperature of the patient; as soon as signs of acute arthritis manifest themselves, free incisions are to be made into the joint, so as to relieve tension and allow of irrigation. If the wound was inflicted by a dirty instrument, the wound should be enlarged, if necessary, so that its depths may be carefully examined and thoroughly cleansed. The cavity should be irrigated and drain- age inserted. . If acute arthritis supervenes, it must be treated in the usual way. Where are salivary calculi most frequently found ?t Give treatment. Salivary calculi are most frequently found in the duct of Wharton. Treatment. — If protruding from orifice of the duct, they may simply be extracted. If within the duct, they should be cut down upon and removed. How should a salivary fistula be treated ? This affection practically always occurs in rela- tion to Stenson's duct. If the buccal portion is in- volved, the duct may be slit up from within the mouth. If the masseteric portion is wounded, a fine probe should be passed into the duct (from the mouth) as far as the fistulous opening, and then brought out at this orifice. A double thread of silk is now tied to the end of the probe and drawn through the thickness of the cheek, along the buccal portion of the duct, and ij8 ORAL SURGERY. out of the external wound. A fine drainage tube is then carried along the same tract, and left to project both externally and internally. A silk thread is at- tached to each end of the tube and knotted around the angle of the mouth. In this manner a passage is re-established into the mouth, and as soon as it be- comes easier for the saliva to travel along this than through the external wound, the fistula will close. The outer half of the tube may be removed in a few days, and only a thread allowed to remain in the ex- ternal wound, which gradually contracts so that more and more of the saliva finds its way to the mouth. The silk thread and tube are finally removed, and, if the canal remains patent, the external wound soon heals. If the buccal portion of duct is obliterated so that the probe cannot be introduced, the thread and tube may be passed through all of the tissues of the cheek by means of a trocar and canal. The subse- quent steps are similar to those of the previous method. How should hemorrhage from the gums be treated ? By means of hot water, cold, compression, perox- ide of hydrogen, styptics, suprarenal extract, or the actual cautery. If due to scurvy, appropriate antiscor- butic treatment; if due to hemophilia, calcium chlor- ide gr. xxx t. i. d. and apply fibrin ferment, supra- renal extract, or cocaine, locally. Define necrosis and give treatment. By necrosis is meant the death of bone en masse. ORAL SURGERY. i 39 Treatment- — Early in necrosis, endeavor to mod- erate inflammation upon which the affection depends and open any abscesses that may form. During the time occupied by the loosening of the dead bone, no operative treatment should be instituted, as a rule, but attention should be given to the general health. As soon as the necrosed portion has become detached, it should be removed. Give the diagnosis and treatment of tetanus. Diagnosis. — Trismus, opisthotonus, emprostho- tonus, or pleurosthotonus. The spasms are tonic in character with clonic exacerbations. Constipation and retention of urine are present. The mind is clear, there is a hypersecretion of sweat, and little or no fever. It may be possible to discover the source of infection. Treatment. — Symptomatic treatment. Chloro- form during the exacerbations of the spasm and chloral between the exacerbations. Feeding at regu- lar intervals (stomach tube, under chloroform), and the periodic evacuations of the bladder by catheter and the rectum by enema. Calabar bean has been highly recommended. Specific treatment. — Trephining and introduc- tion of anti-toxin beneath the dura. Local treatment. — Antiseptic treatment of wound. What is a dislocation ? Name the varieties, and give the causes. A dislocation is a displacement of one or more 140 ORAL SURGERY. bones of a joint from its natural position. It is also the displacement of any organ from its natural posi- tion. Traumatic. — Due to violence or muscular action. Pathologic. — Due to disease. Congenital.- — Due to an error of development as a result of which a normal location of the bony con- stituents has never been present. (The term con- genital "dislocation" is really a misnomer — it is a congenital malformation.) What is an incised wound ? Give the prognosis and treatment. An incised wound is one made by any sharp cut- ting instrument. Prognosis. — Nearly always favorable, but de- pends upon the region involved and asepsis of the wound. Treatment. — Arrest hemorrhage. Render the wound as aseptic as possible. Unite the edges of the wound by means of sutures and apply a (Septic dressing. Give diagnosis and treatment of caries. The symptoms of caries are those of osteitis com- plicated by an abscess leading to the softened bone. When caries is primary, it particularly involves the cancellous tissue (ends of long bones, flat bones) . The pus from carious bone contains an excess of phos- phate of lime. Treatment. — If syphilitic, give potassium iodide; if tubercular, cod-liver oil with iodide of iron. Secure *> ORAL SURGERY. 141 best hygienic surroundings. In early stages while the disease is advancing, keep the parts clean and free from irritation. When acute symptoms have sub- sided, an attempt may be made to remove the diseased bone by applications of iodine or of the mineral acids. If the carious bone can be reached from the surface, it may be removed with a gouge or with a burr-head drill. If the disease is extensive, excision may be required. In some cases amputation is necessary to prevent fatal exhaustion. How may general infection be caused by oral operations ? The wound in the buccal cavity may become in- fected by any of the micro-organisms found within the mouth. From this local source, the bacteria, their products, or both, may pass into the general circula- tion. Give the symptoms and treatment of acute sup= purative periostitis. If the bone is superficial, there will be all of the symptoms and signs of inflammation. If the bone is deep, redness, swelling, and heat may not be ob- served over the inflamed area, on account of the density of the periosteum. The pain is of a most intense, aching character, worse at night, and greatly increased by pressure or by a dependent position of the part. If swelling is present, it is brawny in charac- ter and subsequently becomes red, edematous and softened in the centre. If the abscess has opened spontaneously or has been incised, bare bone is ex- posed, the greater portion of which usually dies. 142 ORAL SURGERY. This dead bone is either absorbed (if very small in amonnt) or cast off as a sequestrum. Treatment. — A free aseptic incision down to the bone at the earliest possible moment. Antiseptic dressing. If necrosis has occurred, it must receive appropriate treatment. Supporting or antidiathetic treatment constitutionally. Give the differential diagnosis between syphilitic and aphthous ulceration. Syphilitic ulcers occur in the shape of cracks or fissures upon the sides or tip of the tongue, or upon the cheeks and lips. They are common in the secondary period of the disease. Papular eruptions of the skin and mucous patches may also be ob- served. These ulcers respond to anti-syphilitic treat- ment. Aphthae commence as small blisters, which run a rapid course and are accompanied by slight saliva- tion, The ulcers are superficial, sharply outlined, multiple, and are situated not only upon the tongue, but particulary upon the cheeks and lips. Give the etiology and symptoms of the congenital malformation known as cleft palate. Etiology.— Failure of the palatal processes to unite. Symptoms. --Inspection reveals a cleft in the median line. If the palatal process of one side has united with the ethmo-vomerine septum, a cleft slightly to one side (usually to the left) of the me- dian line is observed. Since the union of the pala- ORAL SURGERY. H3 tal processes takes place from before backward, it is rare to have a cleft of the anterior portion of the palate without the posterior portion being also in- volved. As a rule, there is considerable impairment of nutrition, from interference with deglutition. The exposure of the nasal mucous membrane leads to the formation of scabs which undergo putrefactive changes, producing a condition somewhat resembling ozaena. When the child learns to talk, articulation is frequently so indistinct that it is difficult to un- derstand, and the voice has a peculiar and charac- teristic intonation. The so-called explosives (whether dentals, labials, or gutturals) which require a certain amount of air-pressure within the mouth for their proper pronunciation, are difficult to produce. This is particularly to be observed in the letters b, d, p, t, g and f. Give the diagnosis and treatment of trismus caused by impacted third molar. Diagnosis.— There is a partial or complete in- ability to open the jaws. Inspection reveals the impaction of the third molar. Necrosis may be present. Treatment.— Relief of the impaction, either by extraction of the offending tooth or of the second molar. If necrosis is present, it must be treated upon general principles. Mention the most reliable agent for the de- struction of micro=organisms. How should it be used ? Heat.— It may . be used in the form of dry heat or moist heat (steam, under pressure if necessary, 144- ORAL S UR GER Y. hot water), It should penetrate to the centre of the material to be sterilized. What diseases of the tongue may be caused by diseased teeth ? Traumatic ulceration, glossitis, abscess, and epithelioma. Describe the preparation of the oral cavity for an aseptic operation. Asepsis, as applied to the oral cavity, is but a relative term. All cavities in the teeth should 'be cleansed, disinfected and filled. The interstices be- tween the teeth must be carefully cleansed and the mouth repeatedly washed out by a boric acid solution as hot as can be borne. The nasal cavity should also be rendered as aseptic as possible, and the patient should gargle repeatedly with hot boric acid solutions. Define a multilocular cyst. A multilocular cyst is one which is composed of a number of loculi or chambers. Describe treatment and appliance for acquired cleft palate. Acquired perforations of the palate are usually due to syphilis, but lupus and traumatism are also occasional causes. Treatment should first be directed to the underlying cause. When inflammatory symp- toms have subsided and nature has done all she can to repair the defect, the local treatment is indicated. If the perforation is small, an attempt maybe made to close it by freshening the edges of the perfora- ORAL SURGER Y. i 45 tion, dissecting up tnuco-periosteal flaps and sutur- ing them together. This will rarely be appreciable, however, and in the great majority of cases an ob- turator or an artificial vellum must be introduced. An obturator is a plate which is so adjusted as to close the perforation. It should never be made in the form of a plug, since the opening may be en- larged by the constant pressure and irritation. It is made of thin vulcanite or gold, and is fixed to the teeth and held in position by suction. Intra-nasal pro- jection will sometimes improve the quality of the articulation by diminishing the size of the nasal cavity. An artificial vellum is a plate obturator, to the posterior portion of which a hinged segment is at- tached, to take the place of the normal vellum. This hinged segment may rest upon the natal side of the soft palate. A thin rubber bag, filled with air and sewn to the posterior portion of the obturator, is sometimes used in place of the hinged segment. Arti- ficial vella are by no means so satisfactory, as a rule, as are the plate obturators. Define odontalgia. Give the etiology and treat= ment of odontalgia. Toothache. It may be caused by many different pathologic conditions of the tooth or surrounding tissues, such as congestion of the pulp, exostosis of the roots, pulp nodules, mechanical or chemical irritation, reflected pains from irritation of areas supplied by other 146 ORAL SURGERY. branches of the fifth nerve (impacted body in exter- nal anditory meatus, etc.), infection, mal-occlusion, exposure of dentine and denudation of roots. Treatment.— Removal of the cause. In the ma- jority of cases the pulp of the tooth must be re- moved. Tincture of iodine to the gums and chloro- form or ^oil of cloves to cavities in teeth, might be mentioned as temporary measures. Describe (a) Sylvesters's method of producing respiration ; (b) Laborde's method of producing artifi= cial respiration. Sylvester's method.— The patient is placed upon his back with a folded coat or a pillow beneath the interscapular region, the throat is cleared of mucus, the tongue held well forward, and all constricting clothing removed from throat and abdomen. The operator kneels or stands behind the patient. The forearms are grasped near the fully flexed elbows and the lower portion of the thorax is compressed for a few seconds by forcing the patient's elbows against the thoracic wall. The arms are then moved out- wards and upwards until the hands cross over the head. This secures elevation of the costal walls and simulates inspiration. The arms are kept in this position for a few seconds and then brought down- ward to the first position, pressure being made upon the costal walls with the elbows of the patient. This simulates expiration. These movements are to be repeated from twelve to fifteen times a minute. Laborde's method. — After clearing the throat of mucus, rythmic traction is made upon the tongue. ORAL SURGERY. i 47 Describe the effect of arsenic upon the pulp of a tooth. The pulp becomes devitalized and there is an absence of the previously existing sensibility, as may be demonstrated by the use of any exploring in- strument. State the pathologic changes in chronic inflam= mation. Dilatation of blood vessels, slowing of current, exudation of fluid, transmigration of leucocytes and multiplication of the pre-existing connective tissue cells of the part. The only difference between acute and chronic inflammation is one of degree. In chronic inflammation the productive changes are much more marked than in the exudative or the degenerative ones. Describe the healing of wounds, irrespective of the anatomic structure of the tissue involved. The healing of an aseptic wound will be de- scribed. There is a certain amount of exudation, re- sulting in the formation of fibrin, which temporarily binds the lips of the wound together. This network of fibrin serves as a framework for the leucocytes and multiplied connective tissue cells. The exudate be- comes vascularized and is then known as granulation tissue. The leucocytes have nothing to do with the building up of tissue. They destroy the fibrin net- work and then either return to the circulation or are fed upon by the connective tissue cells or fibroblasts. The fibroblasts soon become spindle-shaped, and their 14.8 ORAL SURGERY. ends become split up into primitive fibrillae. This con- version of the round fibroblasts into the connective tis- sue fibre results in the contraction of the cicatrix, which binds the lips of the wound tightly together. PATHOLOGY AND THERAPEUTICS. What changes occur in inflammation ? Primarily. — A marked increase in the velocity of the blood-current and a dilatation of the vessels (ar- teries and capillaries), caused by a stimulation of the vaso-dilator, or a paralysis of the vaso-constrictor, nerves, followed by a decrease in the velocity of the blood and increased pressure with heightened temper- ature and redness. Leucocytes collect along the walls of the vessels and migrate through them by a process called diapedesis. Exudates pour into the intercellular spaces and the part becomes swollen, causing pain by pressure upon the nerve filaments. If resolution oc- curs, the inflammatory effusions will be taken up by the lymphatics and the part restored to health. If, on the other hand, suppuration occurs, death of the part, or necrosis, may follow. What is septicemia and what causes it ? It is a condition in which septic matter gains ac- cess to the circulating fluids of the body, caused by the absorption of the toxic poisons produced by bacteria. How do you treat putrescent pulps ? The contents of the pulp cavity and canals should be sterilized with a ten percent, solution of formalin, after which the pulp should be removed with steril- ized broaches, great care being exercised not to force any of the canal contents into the apical space. Canals ISO PATHOLOGY AND THERAPEUTICS- should then be thoroughly washed with a ten percent, solution of sodium dioxide, followed by an application of dilute sulphuric acid. Neutralize the acid with a bicarbonate of soda solution, dry with absolute alcohol and fill canals with antiseptics on cotton, or fill per- manently as indicated. What symptoms indicate diseases of the dental pulp? Paroxysms of pain upon application of thermal test, pain upon assuming the recumbent position, neuralgic pain along the course of the fifth nerve, and pain upon percussion. Why is a pulp capped ? When ? How ? To preserve its vitality. In young patients when the pulp has been exposed by accident in excavating. Make a concave disc of gold> platinum, tin or copper, large enough to completely cover the exposure; fill the disc with a paste made from zinc oxide and one of the essential oils, place this over the exposure and seal over with zinc oxysulphate. Cover the whole with a temporary filling. If pulp continues vital and normal for three months or six months, it is reason- ably safe to insert a permanent filling. What do you mean by pyorrhoea alveolaris ? It is a disease of the peridental membrane in which this organ, together with the alveolar process, undergoes necrosis, causing, as a rule, a flow of pus, and recession of the gum tissue. How do you distinguish erosion of the teeth and caries? PATHOLOGY AND THERAPEUTICS, 151 Erosion of the teeth differs fiom caries in so much as it is due entirely to the action of an acid from the buccal glands upon the tooth structure, and can be distinguished from caries by the polished and trans- lucent appearance of the underlying dentine. Caries presents a softened surface due to decalcification. Which tissue of the tooth dies with the pulp, and which remains alive ? The dentine dies with the pulp, and the cemen- tum remains alive. How is the destruction of tissue brought about in dental caries ? It is brought about by the action of lactic acid, the product of carbo-hydrate fermentation through the agency of bacteria, which dissolves out the inor- ganic constituents of the tooth, leaving the organic material to be peptonized and dissolved by bacteria. What are parasitic bacteria, and how do they cause disease ? Parasitic bacteria are those forms which subsist upon living animal tissue, producing toxic poisons known as toxalbumins, which, when absorbed into the circulation, cause disease. How does mercuric chloride act as an antiseptic ? Mercuric chloride acts as an antiseptic by de- stroying bacteria The mercury in the compound when brought into contact with albuminous sub- stances, combines with the albumen, thereby destroy- ing its identity, as well as its vitality. 152 PATHOLOGY AND THERAPEUTICS. What are some of the manifestations of patho= logical dentition ? In deciduous pathological dentition, we may have gastro-intestinal disturbances, marked stomatitis and, in severe cases, convulsions may occur. In perma- nent dentition, some of the pathological conditions most frequently met with are impaction or eruption in malposition of third molars, impaction of lateral incisors, supernumerary teeth, fusion, irregularities as to the number of cusps, odontoceles and dentiger- ous cysts. What are the principles of treatment in dental caries ? The employment of an alkaline solution to neutralize acids present, removal of carious material, the destruction of micro-organisms by the use of germicides and the hermetical sealing of the cavity by means of rilling materials. What is the danger of chronic septic pericemen= titis, and what is the treatment ? The danger is the opening of the pus cavity upon the face, or the infiltration of pus into the tis- sues surrounding the tooth, causing necrosis of the pericemental membrane and loss of tooth. The treatment consists of the mechanical removal by warm water of pus masses and the antiseptic treat- ment of the affected part, after which mild stimula- tion should be employed to hasten the formation of granulation tissue. Name four agents used in acute diseases of the pulp and give the physiological action of each. PATHOLOGY AND THERAPEUTICS. ijj Tr. Aconite administered in one drop doses re- duces the force of the circulation and acts as a seda- tive to the nervous system. Carbolic acid, being antiseptic and sedative in its action, may be used in cases of hyperaemia of the pulp. A saturated solution of menthol in chloroform, if placed in a cavity of a tooth exhibiting symptoms of pulpitis (acute), has an anesthetic and antiseptic effect. A paste of cocaine and glycerine may also be used in cases of pulpitis and acts as an analgesic. What causes an alveolar abscess ? Access of septic matter to the apical space or direct bacterial invasion of that area during an attack of apical pericementitis. What is phagedenic pericementitis ? A disease of the pericemental membrane produc- ing necrosis of that organ. In this particular condi- tion, calcareous deposits may be present and gingi- vitis may not be marked. How do you diagnose exostosis ? Exostosis is accompanied by the presence of vaguely reflected pains, it being usually impossible to locate the seat of the trouble ; the X-ray, however, demonstrates the condition very efficiently. What causes induce periodontitis ? Traumatism and septic infection. What dangers are to be apprehended from abscess upon the temporary teeth ? 154 PATHOLOGY AND THERAPEUTICS. Pus gaining access to the follicle of the perma- nent successor interfering with its development. Non-resorption of the deciduous root causing mal-erup- tion of permanent tooth. Possible necessity for pre- mature extraction of the temporary tooth, resulting in impaction or mal-eruption of permanent tooth. What results are likely to follow abrasion of the teeth ? Heightened sensitivity of the dentine and de- posits of secondary dentine in the pulp cavity. What causes superinduce the devitalization of non=carious teeth ? Traumatism, causing severe hyperaemia and death of the pulp by strangulation. This includes too rapid wedging as well as too rapid movement in regulating cases. How would you conduct a thermal test to locate an inflamed pulp? By isolating each tooth with rubber dam and projecting against it, alternately, jets of cold and hot water, until the offending member has been located by an exaggerated response to the test. What is necrosis ? Give some causes. Necrosis is the death of any tissue en masse caused by an interruption in the process of nutrition. Causes. — Thrombus in a terminal artery ; or, liga- tion of a vessel cutting off the supply of nutrition to the part. Which of the permanent teeth are most liable to to pathological eruption, and why ? Define pathology. PATHOLOGY AND THERAPEUTICS. 155 The upper and lower third molars. The former frequently erupt with their occlusal faces directed toward the cheek owing to an insufficient space be- tween the second molars and the pterygoid processes for their accommodation normally within the arch. The lower third molars are more frequently retarded in their eruption, also due to lack of space. Pathology is the study of tissues in an altered physiological condition. Describe epulis within tooth cavity. Describe fun= goid pulp. Epulis within a tooth cavity is a pedunculated fibrous growth gaining access to the cavity usually through an opening at the bifurcation of the roots of molar teeth. This opening is caused by caries. The condition resembles very closely fungoid pulp, a hy- pertrophic condition of the pulp which is fibrous in character and highly vascular. What is resorption of the roots of deciduous teeth ? Is it a physiological or a pathological condition ?. Resorption of the deciduous roots is a physiologi- cal condition brought about by the action of giant multinucleated cells, probably modified leucocytes; these dissolve the substance of the roots, which is then taken up and carried away by the circulation. This condition is stimulated by pressure caused by the growth of the permanent successor. In what abnormal condition will resorption of the temporary teeth cease ? In temporary teeth containing putrescent pulps, ij6 PATHOLOGY AND THERAPEUTICS. or a devitalized pericemental membrane in a sup- purating condition, resorption does not occur. Describe and give the supposed causes for Hutch= in son's teetti. Hutchinson's teeth present a notched appear- ance upon the cutting edges, the longitudinal axes of these edges being shortened. The supposed cause is congenital syphilis. How is pulp irritation from loss of tooth substance distinguished from sensitive dentine ? If exaggerated pain is experienced from contact with instruments upon the abraded surface, the condition is that of sensitive dentine. If this contact causes but a mild response and the thermal test pro- duces marked paroxysms of pain, the condition may be diagnosed as irritation of the pulp. What results may follow the premature extraction of the temporary molars ? The first permanent molar may tip forward and occupy the space which the second bicuspid should take upon eruption, thereby causing either mal-erup- tion or impaction of the bicuspid tooth. How would you differentiate between pericementitis and alveolar abscess ? In pericementitis, the pericemental membrane becomes thickened, the tooth elongated and extremely sensitive to percussion. A reddening of the gum tissue is noted over the affected tooth. In alveolar abscess we have an exaggerated likeness to these PA THOL OGY AND THERA PE UTICS. 157 symptoms together with swelling over the affected tooth, intense pain with a subsequent discharge of pus. Name some of the pathological conditions of the dental pulp. Passive and active hyperaemia, pulpitis, pulp nodules, dry and moist gangrene and pulp hyper- trophy. Give the cause of dental exostosis and describe the symptoms. The cause of dental exostosis may be extraction of the occluding tooth, the pericementum not being met by the accustomed resistance, proliferates cementum upon the apex of the root. Or, traumatic injury, caus- ing continued mild irritation of the pericementum, may give rise to a like condition. The symptoms are gnawing pains in the affected tooth, sometimes assum- ing a reflected neuralgic type. Mow would you diagnose and locate an inflamed pulp where no cavity exists ? By the thermal test. What is meant by the pathology and morbid anatomy of a disease ? By the pathology of a disease is meant the study of the alterations in physiology which lead up to it, i. e., its pathogenesis. By morbid anatomy of a disease is meant a consideration of the altered ana- tomical conditions. What are bacteria ? Distinguish between sapro- phytic and parasitic. i £8 PATHOLOGY AND THERAPEUTICS. Bacteria are minute organisms representing the lowest order of plant life. Saprophytic bacteria sub- sist upon dead organic matter, while the parasitic variety derive their nourishment from living organ- isms. , - Give the symptoms of septicaemia. The general symptoms of septicaemia are fever and chills, diarrhoea, rapid and weak pulse and clammy condition of the skin. If the infection has been from a wound, the discharge coming from it will be putrid. What conditions are necessary for the growth and development of bacteria ? Proper food supply, removal of waste products, moisture, sufficient temperature and the presence of free oxygen. This last named condition, however, is not necessary for the existence of the anaerobic bacteria. How do bacteria multiply ? Bacteria reproduce through the medium of spores, and by fission. Give Miller's theory of dental caries. The presence of sugar in the mouth causes fer- mentation and the production of acids which dissolve out the lime constituents of the teeth. Micro-organ- isms gain access to the dentinal tubuli and prolifer- ate; they follow in the wake of the decalcifying pro- cess and subsist upon the organic tooth substance, producing acids. PATHOLOGY AND THERAPEUTICS. 159 By what and under what conditions is pus pro= duced ? Pus is produced by the invasion of the staphylo- coccus pyogenes aureus, citreus or albus, or by strepto- coccus pyogenes, the gonococcus, the bacillus pneu- monae or other pyogenic organisms into an area sus- ceptible to inflammatory changes, or already inflamed. The white blood corpuscles together with other wan- dering cells of the body, are devitalized by the bac- teria and become pus corpuscles. What are leucocytes and what are their functions ? Leucocytes are the white blood corpuscles. They exercise phagocytic activity, devouring and carrying away invading bacteria and other irritating organic substances which gain access to the tissues. How is fermentation produced ? Fermentation is produced by the action of micro- organisms upon solutions of organic substances ex- posed to the air. Name some of the pathogenic fungi found in the mouth. Micrococcus of sputum septicaemia. Bacillus salivarius septicus. Micrococcus gingivae pyogenes. Saccharomyces albicans. Pneumo-bacilliis. What is meant by lactic fermentation and why is it of extreme interest to dentists? Lactic fermentation is that process or change which occurs in solutions of the fermentable carbohy- 160 PATHOLOGY AND THERAPEUTICS. drates, producing lactic acid. This product is of in- terest to dentists, as it is the prime factor in the pro- duction of dental caries. How are cultures of bacteria made ? Cultures of bacteria are made by first arranging a suitable medium, or field for the growth of the or- ganisms. Bouillons, gelatinous fluids, gelose, po- tato, serum, etc., are used for this purpose. The me- dia are usually sterilized by heat. The infected mat- ter is placed upon the medium and subjected, as a rule, to a proper temperature in an incubator. Name three recognized classes of bacteria. Bacteria are classed according to their form as micrococci (spherical), bacilli (rod- like) and spirillae (curved). Through what channels do bacteria gain access to the system? They gain access through open wounds or breaks in the skin, or mucous membrane, and by the mouth or nose into the gastro-intestinal tract, and lungs, where they enter through the mucous membrane. What is meant by regeneration of tissue and how is it brought about ? By regeneration is meant the return of a tissue to a state of normality after its having been the seat of inflammatory processes. This is brought about by the removal of the inflammatory effusions by the phagocytic action of leucocytes and absorption by the lymphatics. Bmbryonic connective tissue now PATHOLOGY AND THERAPEUTICS. 161 appears and a network of newly formed blood vessels is constructed in it by a process of budding. This mass is known as granulation-tissue. Most of the newly formed vessels undergo atrophy after perfect regeneration has occurred, leaving a pale area or cicatrix. What effects may be produced in the mouth from the administration of large doses of calomel? Describe the condition. Large doses of calomel produce a condition known as mercurial stomatitis. The gums around the necks of the teeth become inflamed and swollen, ulceration of the mucous membrane occurs, the teeth become loosened, and there is a marked increase in the flow of saliva. The breath is fetid, and there is an unpleasant metallic taste in the mouth. The severity of these symptoms depends upon the suscep- tibility of the patient, as, in some cases, loss of the teeth occurs, and even necrosis of the maxillary bones. Give the differential diagnosis between an abscess and a cyst. The development of an abscess is accompanied by the most extreme pain and does not show exter- nally any alteration in the anatomy of the part, until the late stage. . A cyst is seen to enlarge, expanding the bone tissue which envelops it, its development being accompanied by a little or no pain. In the dentigerous cyst, pressure upon the walls produces crepitation or crackling. 162 PATHOLOGY AND THERAPEUTICS. Differentiate between hyperaemia, inflammation and suppuration. Hyperaemia is an excess of blood in a part. In- flammation is the succession of changes (hyperaemia being one of these changes) which occnr in a tissue during its effort to rid itself of an irritant, provided the irritant is not of sufficient strength to cause im- mediate death of the part. If, in the last stages of inflammation, resolution does not occur, and pyogenic organisms invade the inflamed area, suppuration, or the formation of pus, will occur. Describe the process of a formation of an apical alveolar abscess. Septic matter, having gained access to the apical space, irritates the part producing hyperaemia, which later assumes the type of apical pericementitis. Dia- pedesis occurs, the white blood corpuscles attacking the micro-organisms, exudates are poured out from the vessels, and the pericementum may be stripped from the root, forming a sac in which the dead leuco- cytes and exudates (pus) accumulate. The abscess will vent itself and discharge either through the pulp canal, at the neck of the tooth, or will burrow through the alveolus and gum tissue at a point in the direc- tion of least resistance. Its entrance to the process is marked by a deep redness of the gum over the apex. Its entrance to the gum tissue produces a lessen- ing of painful tension and causes a tumefaction of the gum and sympathetic swelling of associate parts. What is the source of nourishment of bacteria ? How do they obtain oxygen ? PATHOLOGY AND THERAPEUTICS 163 Bacteria contain no chlorophyl, and, therefore, have not the power to decompose water and carbon dioxide nor to effect the synthesis of starch. Hence, they are compelled to derive their nourishment from existing organic compounds. According to their method of obtaining oxygen, bacteria are divided into three classes : anaerobic, those depending upon the presence of free oxygen ; aerobic, those not requiring free oxygen, as they possess the power to appropriate the oxygen from unstable organic combinations ; and facultative or those which flourish in either condi- tion. What is salivary calculus, where is it found, and what effect has it ? Salivary calculus is a deposition of the salts of lime (carbonate and phosphate), held in solution in the saliva, upon the surfaces of the teeth, usually near the gum margin, in proximal spaces and deep sulci. Carbon dioxide plays an active part in the precipitation of the calculus. Large deposits are fre- quently found near Steno's duct, the opening of the parotid gland, and on the lingual and labial surfaces of the lower anterior teeth. Deposits of tartar have the effect of producing recession of the gum, causing sufficient irritation at times to produce inflammation and even suppuration. If allowed to continue, the deposits may be responsible for affections of the peri- cemental membrane and alveolar process, and also tooth loss. What is the difference between an antiseptic and a germicide, and give examples ? ' Antiseptics prevent the action of pathogenic or- 1 6 £ PA THOL OGY A ND THERA PE UTICS. ganisms and their products on the living body, but do not necessarily kill the micro-organisms. Germi- cides destroy the vitality of the germs of disease. They are antiseptics, though antiseptics are not neces- sarily germicides. Iodoform is an antiseptic; mer- curic chloride is a germicide. What is pyrozone ? How does it act, and for what is it used ? Pyrozone is a solution of hydrogen dioxide in water or ether. A 3% aqueous solution acts as an antiseptic and disinfectant; these properties are due to the setting free of oxygen when the solution is brought in contact with organic matter. In this strength, it is valuable in cases of ulcerative stoma- titis, and also in softening deposits of calculus. For cleansing pus pockets, it is an effective agent. A 25% ethereal solution is used as a bleaching agent, caustic and styptic. How are the diseases of the pericementum diag= nosed from those of the pulp ? Diseases of the pericementum respond freely in paroxysms of pain to any pressure brought to bear upon the tooth, while pulp disorders are demonstrated by the thermal test. Pericemental disorders can al- ways be located by the patient. Pains from pulp affections are more often reflected. When one is com- plicated by the other both symptoms may be in evi- dence. At what age is the first permanent tooth erupted, and which tooth is it ? The first permanent tooth is erupted at about PATHOLOGY AND THERAPEUTICS. i6 5 the sixth year; it is called the first molar, or sixth year molar. How do you treat hypersensitive dentine ? In the treatment of hypersensitive dentine the rnbber dam should be applied if possible and abso- lute dryness secured. This, in itself, ofttimes produces sufficient anaesthesia to permit instrumentation. In obstinate cases, however, it may be necessary to em- ploy other therapeutic measures. If the cavity be not deep, a solution of caustic soda (ten grains to the ounce of water) is sometimes effective. A paste of cocaine muriate and glycerine, sealed in the cavity for 24 hours, may be used with good results. Cocaine may also be employed by cataphoresis. Carbolic acid, chloroform, ethyl or methyl chloride (in spray) are also indicated. In cases of hypersensitivity of abraded teeth (where no cavity exists), the tooth or teeth should be isolated by the rubber dam and strong mineral acids, such as nitric, sulphuric and hy- drochloric should be applied. These agents coagu- late the contents of the tubules. The surfaces, treated in this manner, should always be excavated and filled. What dangers must be guarded against in the use of arsenic for devitalizing the pulp of a tooth ? Arsenic, for the purpose of devitalizing the pulp, should be employed with great care. If carelessly applied, a minute portion may come in contact with the gum tissue or be insinuated in the gingival space, producing sloughing of the peridental membrane and 1 66 PATHOLOGY AND THERAPEUTICS. gum tissue, or necrosis of the process, or both. Great care should be exercised in sealing arsenic in a cavity to prepare the margins of the cavity in such a way as to permit hermetical sealing. Pastes of arsenic should be applied without an excess of fluid, as there is danger of oozing about the margins during the process of sealing. This drug should never be used for the devitalization of pulps in deciduous teeth. Give the differential diagnosis between hype= raemia, inflammation and suppuration of the pulp. In hyperaemia the pulp responds to the applica- tion of heat or cold in a somewhat exaggerated degree, owing to the dilatation of the vessels. Cases of hyperaemia usually give a history of mild attacks of odontalgia, transient in character. In inflamma- tion of the pulp the response to cold is somewhat diminished ; the application of heat produces pain of a severe type. Odontalgia becomes constant, throb- bing in character, increasing when the patient resumes a recumbent position. Neuralgic pains ma}^ be felt along the course of the fifth nerve. Suppuration begins in the late stage of inflammation, and is indi- cated by a cessation of response to cold applications. Heat produces agonizing paroxysms of pain only alleviated by the immediate application of cold. The pain now assumes a gnawing character, persistently increasing, while throbbing ceases. What are the principles of treatment in pyor= rhoea alveolaris ? The removal of all existing calcareous deposits ; the washing out of the gingival spaces with warm PATHOLOGY AMD THERAPEUTICS. i6y antiseptic alkaline solutions ; the polishing of all sur- faces of the teeth ; and the employment of stimulat- ing antiseptic germicidal mouth washes. The em- ployment of constitutional tonics is also indicated. What are saprophytic bacteria, and how do they cause disease ? Saprophytic bacteria are those forms which flourish upon dead organic substances, effecting their decom- position, producing toxic poison, through the agency of which they become causes of disease. What objections are there to the premature ex- traction of the temporary teeth ? Premature extraction of the temporary teeth is followed by insufficient space for the normal eruption of their permanent successors, resulting in malposed permanent teeth, and, not infrequently, their im- paction. PATHOLOGY. What are spores ? How may nutrient media be freed from spores at a temperature below ioo degrees C. ? Spores are reproductive bodies of lower vegeta- ble organisms (of bacteria, for example). Nutrient media may be freed from spores at a temperature below ioo° C. by the process of frac- tional sterilization. The nutrient media are exposed to a temperature of 8o° C. for 15 minutes. This destroys the bacteria and the media are then kept at the room temperature for 24 hours so that the spores may develop into bacteria. These bacteria are de- stroyed by an exposure to 8o° C. for 15 minutes upon the second day. This process is repeated the third and sometimes the fourth day, at which time the media will be free from spores. Define Pathology. Pathology is that branch of medical science which treats of modifications of function and changes in structure caused by disease. Define leukomains. State where they are found. By leukomains are meant any of the nitrogenous bases or alkaloids normally developed by the metabolic activity of living organisms, as distinguished from the alkaloidal substances developed in dead bodies and called ptomains. They have been found in almost all of the tissues of the body. PATHOLOGY. i6 9 ilention the different kinds of tumors of the gums ? Simple epulis (fibroma), malignant epulis (mye- loid sarcoma), round-celled sarcoma, spindle-celled sarcoma, and epithelioma. State the difference between parasites and sapro= phytes. A parasite is an animal or vegetable organism living upon or within another living organism. A saprophyte is a vegetable organism living upon dead organic matter. How may inflammation terminate ? Inflammation may terminate by resolution, re- trogression (the formation of cicatricial tissue), sup- puration, ulceration, or gangrene. Name the various tumors of the tongue. Papilloma, fibroma, lipoma, myxoma, angioma, lymphangioma, and epithelioma. Lymphadenoma and lymphosarcoma may occur at the root of the tongue. Chondroma has also been found in the sub- mucous tissue of the tongue. What is the most common syphilitic lesion upon the tongue ? Mucous patches. What is inflammation ? Inflammation is the succession of changes which occur in a living tissue when it is injured, providing the injury is not of such a degree as to at once de- stroy its structure and vitality (Burdon Sanderson). jyo PATHOLOGY. It is " the response of living tissue to injury." Define sepsis, asepsis. Sepsis is a condition of poisoning produced by the absorption of putrefactive substances. Asepsis is the absence of pathogenic micro- organisms. Give the differential diagnosis between sarcoma and carcinoma. A sarcoma arises from connective tissue, may occur at any age, may be encapsulated, gives metas- tasis through the blood vessels, and the overlying in- tegument frequently contains dilated veins. A carcinoma arises from epithelial tissue, usually occurs after middle life, is never encapsulated, and gives metastasis through the lymphatic vessels. What is the difference between a ptomain and a toxin ? A ptomain is a basic compound resembling the alkaloids, formed during the decomposition of animal or vegetable tissues. A toxin is an} 7 poisonous substance, either albu- minous or basic, produced by the action of bacteria upon organic matter. A toxin is a poisonous ptomain. Name three tumors of the superior maxilla and give the pathology of one. Osteoma, carcinoma, and sarcoma. Sarcoma originates from the anterior wall or from the cavity of the antrum or from the spheno- PATHOLOGY. i 7 i maxillary fossa behind the bone. The maxilla may be secondarily involved by sarcomatous nasopharyn- geal polypi which extend from the nose. These growths frequently contain considerable ossific de- posits and this is occasionally so extensive that the antral cavity is obliterated and the bone converted in- to a solid mass. Name tumors of the buccal parietes. Papilloma, naevus, cavernous angioma, and epi- thelioma. Mention four forms of abscesses. Acute or hot, chronic or cold, residual, and me- tastatic. What is an embolus? An embolus is a particle of fibrin or other ma- terial which is swept into the blood current and which is capable of forming an obstruction at its place of lodgment. What is an aneurism ? Mention three varieties. An aneurism may be defined as a sac containing blood and communicating with the interior of an ar- tery. Fusiform, saccular and dissecting. Mention five forms of inflammation. State how inflammation may terminate. Fibrinous, diphtheritic, suppurative, hemorr- hagic and' gangrenous. Inflammation may terminate in resolution, re- trogression, suppuration, ulceration, or gangrene. 172 PATHOLOGY. What are the active agents in decomposition ? The active agents in decomposition are the sapro- phytic bacteria. Define pasteurization. How does pasteurization differ from disinfection and sterilization ? Pasteurization is a process of checking fermen- tation in organic fluids by heating them to 60 ° or 7o°C. It differs from disinfection since, in disinfection , the bacteria are destroyed by the use of chemical agents. It differs from sterilization, since in sterilization, the temperature is carried higher and the bacteria are destroyed, whereas in pasteurization the temperature is simply raised to a point where few fungi can flourish. Give the lesions in syphilitic affections of the buc- cal mucous membrane. The initial lesion (chancre) may rarely occur in this situation. In secondary syphilis there is often a chronic inflammation of the buccal mucous mem- brane and mucous patches (mucous tubercles, con- dylomata) are not infrequently present. State what micro=organisrns produce pus. Staphylococcus pyogenes aureus, staphylococcus pyogenes albus (staphylococcus epidermidis albtis), staphylococcus pyogenes citreus, streptococcus, bacil- lus coli communis, bacillus typhosus, pneumococcus and gonococcus. Describe the structure of a bacterial cell. PATHOLOGY. i 73 The cell is principally composed of an albumin- ous substance known as mycoprotein. There is a large nucleus situated in the centre of the cell consti- tuting its great bulk. This is surrounded by a very delicate cell-wall. In some bacteria, cilia or flagella may be observed extending away from the cell-wall. In other bacteria, the cell-wall seems to undergo a gelatinous transformation so that the bacteria seem to be surrounded by a halo or capsule (pneumococcus). State the difference between benign and malig- nant tumors, Benign tumors are usually encapsulated, do not give metastasis, do not recur upon removal, produce no cachexia, grow slowly, do not infiltrate, are not pain- ful (except by pressure), and do not cause death (ex- cept by location). Malignant tumors are never effectively encapsu- lated, give metastasis, recur upon removal, produce cachexia, usually grow rapidly, infiltrate, are pain- ful, and cause death. What is the usual source from which pathogenic bacteria are derived ? State the conditions under which m,cro=organisms get into the air. Pathogenic bacteria are practically always derived indirectly from the bodies of diseased human beings or lower animals. They may be inhaled with the air (tuberculosis), ingested with the liquids or food (cholera and typhoid), or gain access through wounds. The micro-organisms get into the air from the soil. The excreta of diseased individuals becomes 114 PATHOLOGY. dried, ground up into dust, and these dust particles loaded with, bacteria are disseminated by the winds. Micro-organisms rarely pass from fluids into the air. Describe a method of making gelatine plates. Three tubes of sterile gelatine are to be liquefied by heat. Tube No. i is inoculated with the infectious material by means of a platinum wire. Tube No. 2 is now inoculated from tube No. i, and tube No. 3 is inoculated from tube No. 2. The contents of these tubes are now poured into three previously sterilized Petri dishes. In all of these manipulations, precautions must be taken to avoid accidental contamination of the culture medium. Differentiate thrombosis and embolism. By thrombosis is meant a clotting of the blood within the heart or blood-vessels. It is due to a slowing of the current, or to an altered condition of the blood or blood-vessel walls. By embolism is meant the obstruction of a blood- vessel (particulary an artery) by a fragment of mat- ter brought from another point. This fragment of matter or embolus may be a detached piece of a throm- bus. How does suppuration spread ? Suppuration spreads by the peptonization of the inflammatory exudate by the pyogenic cocci. It spreads in the direction of least resistance. Describe Miller's theory of dental caries. The lactic acid, generated from starchy foods by the organisms of lactic acid fermentation, dissolves the calcium salts from the teeth, leaving the organic PATHOLOGY. i 75 constituents which are then destroyed by the organ- isms always present in the mouth. These organisms are able to carry on their work indefinitely, since the lactic acid is quickly neutralized in the process of tooth solution and the germs do not die of poisoning by their excreta. State the usual method of cultivating bacteria. The usual method of cultivating bacteria is to in- oculate any of the ordinary culture media with the bacteria in question, and then to keep the media under conditions favorable for the growth of the micro-or- ganisms. Bouillon, agar agar, potato, etc. may be kept in the brood-oven; gelatine is kept at room- temperature. Define oral pathology. Oral pathology is the study of the modifications of function and changes in structure as they occur in the mouth and adjacent parts. Hention the principal diseases of the maxillary bones. Osteo-myelitis and its sequelae, alveolar ab- scesses, periostitis, tuberculosis, syphilis (gummata), osteoma, chondroma, fibroma, myxoma, carcinoma, sarcoma, and empyema (upper jaw). Describe the histologic structure of carcinoma. The structure will vary according to the region involved. The tumor is made up of epithelial cells and a stroma of connective tissue. In epithelioma of the skin, the cells are of a squamous type; in carcinoma of iy6 PATHOLOGY. mucous membranes, they are cylindrical and there is a tendency to the formation of cuboidal epithelium. The cells show secondary changes (dropsical infiltra- tion, mucoid degeneration, fatty degeneration, etc .). Karyokinetic figures may be abundant and are fre- quently atypical. The epithelial cells are usually grouped into acini or into alveoli containing several layers of epi- thelial cells. At the periphe^ of the acini, the cells may break through the basement membrane. The connective tissue stroma is of varying den- sity, but is always of a fibrous character. It is arranged so as to form hollow spaces which contain the epithe- lial cells. What are the active causes of carcinoma of the buccal cavity ? Any irritation such as smoking, a sharp tooth, the stem of a pipe, or a badly fitting plate. Leuko- plakia, chronic glossitis, and probably caustics. What is the cause of pain in inflammation ? The pain in inflammation is caused by the exu- date stretching and pressing upon the filaments of the sensory nerves. Another factor in the production of inflammatory pain is the chemical irritation of the sensory filaments by the toxins produced by the bac- teria. What is the difference between catarrhal and sup= purative inflammation ? In catarrhal inflammation there is usually con- siderable liquid exudation, retension cysts may PATHOLOGY. i 77 form in the mucous glands, and even localized ero- sions may appear. There is a hypersecretion of mu- cus and a desquamation of epithelium. In suppurative inflammation, the exudate con- tains a large amount of leukocytes which are killed and transformed into pus cells. What is periostitis ? Periostitis is an inflammation of the periosteum. What is provisional callus, and where is it found ? Provisional callus is the temporary splinting ma- terial which nature throws out about the ends of fractured bones. It is found outside of the ends of the fragments (ring callus) and within the medullary cavities of the fragments (pin callus). Give some of the pathologic and anatomic charac- teristics of a benign tumor. Benign tumors usually resemble the tissue from which they grow, tend to unlimited growth, are en- capsulated, do not adhere to surrounding structures, do not infiltrate, do not give rise to metastasis, do not recur when thoroughly removed, have a nutrition which is independent of the general nutrition of the body, and do not cause death (except mechanically). What is meant by intermediate or definitive cal- lus ? Where is it found ? Definitive callus is the callus which ultimately unites the fragments of fractured bone. It is the metamorphosis of this tissue that results in bony union. 178 PATHOLOGY. It is found between the ends of fractured bones. What effect has increased nutrition on tissues ? It may result in fatty infiltration, in more rapid growth, or in hypertrophy. What effect has imperfect nutrition on tissues? It causes them to degenerate and atrophy. Differentiate between syphilitic and congenital cleft palate. Syphilitic perforation is practically always due to a broken down gumma. There will be a history of preceding syphilis and concomitant lesions in some portion of the body. The perforation will have been accompanied by marked inflammatory symptoms, well remembered by the individual. Congenital cleft palate is present at birth and is due to a failure of union of the two palatal processes. Differentiate fibrous from sarcomatous epulis. Fibrous epulis grows slowly, is hard, painless » pale-red, and rarely attains a larger size than that, of a walnut. Sarcomatous epulis grows rapidly, is softer, pain- ful, livid in color, ulcerates sooner, and may attain the size of an apple . riention the tumors of the buccal cavity. Fibroma, lipoma, myxoma, chondroma, osteoma, lymphadenoma, lymphosarcoma, spindle-celled sar- coma, myeloid sarcoma, papilloma and carcinoma. Define abscess. State of what the walls of an abscess consist and describe its growth. PATHOLOGY. i 79 An abscess is a circumscribed collection of pus in a cavity of abnormal formation. The walls consist of granulation tissue. The vessels of the affected area become dilated and the various elements of the blood pass through the walls. As the pyogenic organisms develop, re- tardation and stasis followed by thrombosis occur successively, whilst the exudation of cells becomes so great that the original tissue of the part disap- pears, after passing through a stage of coagulation necrosis. This removal of the infiltrated tissues is largely caused by their liquefaction, owing to the peptonizing power of the bacteria. State how a dead pulp may cause empyema of the maxillary sinus. The dead pulp may become infected and give rise to an alveolo-dental abscess, which ruptures into the maxillary sinus or causes a purulent inflamma- tion of its lining by contiguity of structure. Define atrophy. Give the etiology and pathologic anatomy of atrophy. Atrophy is a reduction in bulk of one or more of the component parts of an organ, and the func- tional activity is reduced. The organ is reduced in size ; its consistency may be increased ; the outline of the organ may be- come irregular and there is an increase of pigment. The microscope shows a reduction in the size of the individual cells. Give an effective method of sterilizing hypoder= mic syringes. 180 PATHOLOGY. The modern hypodermic syringe consists en- tirely of metal and can be effectively sterilized by boiling it for five minutes in a \% solution of sodium carbonate. If boiling water is drawn up into the old glass and metal syringe and then ejected, and this is re- peated six or eight times, the syringe will be practi- cally sterile. This method is more reliable than solutions of carbolic acid or bichloride (Eiselsberg). State in what manner micro=organisms enter the body. Through the respiratory tract, through the gas- tro-intestinal tract, through solutions of continuity of the skin and mucous membranes, and through the placenta. State the difference between asepsis and anti- sepsis. In asepsis, an effort is made to prevent the en- trance of germs into a wound. The greatest reliance is placed upon mechanical purification and upon sterilization by heat. In antisepsis, an effort is made to destroy the germs in a wound as well as to prevent the entrance of more bacteria. The greatest reliance is placed upon chemical agents. How and under what conditions do bacteria mul= tiply ? Bacteria multiply by fission (direct division), and by sporulation (development of spores). The following conditions are requisite for the multiplication of bacteria : PATHOLOGY. 181 i. Presence of oxygen (aerobic bacteria). Ab- sence of oxygen (anaerobic). 2. A certain amount of organic matter. 3. A certain amount of moisture. 4. A neutral or feebly alkaline reaction, for the majority of bacteria. 5. A temperature above 16 ° C and below 40 C. 6. The majority of bacteria multiply most rapidly when the medium in which they grow is at rest. Define toxin, antitoxin, ptornain, virulent germ, non=virulent germ. A toxin is any poisonous substance, either albu- minous or basic, produced by the action of bacteria upon organic matter. An antitoxin is a counter poison elaborated by the body to counteract the toxins of bacteria. A ptornain is a putrefactive alkaloid formed dur- ing the decomposition of animal or vegetable tissues. A virulent germ is one having marked patho- genetic properties. A non-virulent germ is one, the pathogenetic properties of which are not marked. Differentiate hypertrophy and tumor. An hypertrophy is an increase in bulk of a tissue or organ occurring independently of the general growth of the body. In a true hypertrophy the func- tion is increased. 182 PATHOLOGY. A tumor is an atypical new formation tending to unlimited growth, having no function, differing from the tissue in which it is found in gross and minute structure, the nutrition of which is independent of the nutrition of the body in general, and which is not dependent upon or coincident with inflammation. What are pathogenic bacteria ? State how patho= genie bacteria incite disease processes. Pathogenic bacteria are those which produce disease. After gaining entrance to the tissues they may incite disease processes in one of the following ways: They may grow so rapidly that they completely block up the blood and lymphatic channels. They may cause a local inflammation due partly to the presence of the foreign organisms and partly to their toxic metabolic products. More often, however, they produce powerful me- tabolic poisons which destroy the tissues immedia- tely acted upon, or circulate through the organisms and overthrow the normal physiologic equilibrium. Define carcinoma. Give with reference to carci= noma ^a) congenital theory, \h\ traumatic theory, (c) clinical appearance. A carcinoma is a malignant epithelial tumor, composed of a connective tissue stroma, surrounding groups or nests of epithelial cells. (a) Congenital theory. — The carcinoma is sup- posed to grow from embryonal rests or "resting spores." PATHOLOGY. i8j (b) Traumatic theory.^-The carcinoma devel- ops as the result of a single traumatism or of re- peated irritations. (c) Clinical appearance. — The tumor occurs in an individual past middle life, is fixed to the surround- ing tissues and may be ulcerated. The neighboring lymphatic glands are enlarged, the tumor is the seat of lancinating pain, and cachexia is present. Distinguish between pathologic regeneration and physiologic regeneration. Physiologic regeneration is that which occurs in the normal life of the organism, and by which the cellular wear and tear is counterbalanced. The tissue destroyed is replaced by similar tissues. Pathologic regeneration is the more massive and open atypical reconstruction that follows disease or injuries. The tissue destroyed is almost always re- placed by connective tissue. What is disinfection ? How may the strength of a disinfectant be determined ? Disinfection is the destruction of micro-organ- isms, particularly by the action of chemicals. The strength of a disinfectant may be deter- mined by bringing definite quantities of the infected material in contact with definite quantities of a series of solutions of graded strengths, and subse- quently making cultures from the infected material, w T hich has been thus exposed, to determine whether the organisms have been completely destroyed. 184 PATHOLOGY* How do wounds heal ? Wounds heal: i. By immediate union. 2. By first intention. 3. By organization of a blood clot. 4. Under a scab. 5. By second intention (granulation). 6. By third intention (adhesion of granulating surfaces) . By the first four methods the wound heals with- out the formation of pus; in the last two methods suppuration is present. riention the different varieties of tumors of the superior maxilla. Myxoma, fibroma, chondroma, osteoma, odon- toma, sarcoma, and carcinoma. Define pus. Give the specific gravity and varie- ties of pus. Pus is a thick, opaque, creamy fluid; it is smooth and slightly glutinous to the touch, has a faint odor and a slightly sweetish taste. It is neutral or feebly alkaline in reaction. The specific gravity of pus varies between 102 1 and 1042. The varities of pus are: Healthy pus, ichorous pus, sanious pus, fetid pus, curdy pus, muco-pus, and sero-pus. Define suppuration. By suppuration is meant the formation of pus. Define diathesis. PATHOLOGY. 185 A state or condition of the body whereby it is especially liable to certain diseases. It may be ac- quired or hereditary. Define cachexia. A depraved condition of general nutrition due to some serious disease, such as syphilis, tuberculosis, carcinoma. Into what classes are bacteria divided ? According to their morphology, bacteria are di- vided into: (1), Cocci, (2), Bacilli; (3), Spirilla. These are relatively monomorphous. Three other varieties might be mentioned, (4), Spirulina; (5), Lepto- thrix; (6), Cladothrix. These are relatively pleomor- phous. Define plethora, anemia, hyperemia. By plethora is meant an increase of the total amount of the blood in the body. By anemia is meant a deficiency of the blood as a whole, a deficiency of the red blood, or of the hemoglobin. By hyperemia is meant an increased amount of blood in the more or less dilated vessels of a part. THERAPEUTICS AND MATERIA MEDICA. What is meant by idiosyncrasy ? A peculiar or abnormal response to the action of a drug. For what conditions in the mouth is sulphuric acid useful ? In what strength and in what manner may it be employed ? In hypersensitive dentine, in simple cavities of decay, to open and enlarge minute root canals. In these cases it is employed in 50% strength, applied with a gold probe and neutralized with sodium bicar- bonate. In about 10% solutions, it may be employed as an aid to remove concretions upon roots. In this strength it may also be employed to remove dead bone. In what manner may the teeth be best protected from the effects of acids administered internally through the mouth ? They should be well diluted and an antacid at at once used to counteract any acidity induced through their use. What is a counter irritant ? Name two used in the mouth. A counter irritant is an agent used to excite vascularity where applied, resulting in the relief of pain and vascularity in other parts, e. g. Capsicum and tincture of iodine. THERAPEUTICS AND MA TERIA MEDIC A. 187 What is the dose of tincture of aconite root ? One to three minims. What is the local action of aconite ? It acts as a powerful sedative, causing tingling and numbness due to paralysis of terminal nerve filaments. What preparation of arsenic is most used in dent- istry, and what is the local action of this preparation ? Arsenous acid in the form of a paste. When brought in contact with the tooth pulp we have congestion, accompanied by grumbling pain which in a few hours becomes acute and throbbing. The blood vessels become strangulated at the apex of the root, resulting in the death of the pulp, also in cessation of pain. What preparation of iron is particularly injurious to the teeth ? Why is it injurious ? Tincture of the chloride of iron. On account of the free acid it contains. Name the drugs that may be combined with arsenic for devitalizing a tooth pulp, and state what pur= poses these drugs serve. Combined with acetate or sulphate of morphine or hydro-chlorate of cocaine, as local anodynes, with an essential oil to make paste and facilitate the ap- plication as well as action. Name three local anesthetics used in dentistry, and state the conditions that call for their application. Cocaine hydrochlorate, carbolic acid, tincture of 188 THERAPEUTICS AND MA TERIA MEDIC A. aconite. Cocaine hydrochlorate, for hypodermic use in extraction. Carbolic acid, where the sensibility of the gum is to be destroyed to permit of painless inci- sion being made. Tincture of aconite, to control pain by its application to the gum tissue in cases of peri- cementitis. What desirable qualities should a disinfectant pos= sess for use in a pulp canal ? Ability to neutralize various products resulting from putrefactive processes, and the attribute pene- trability. What conditions about the mouth call for the use of iodine, and what are its effects ? In pericementitis, in oedema of cheeks or lips, as an aid in removing green stain from the surfaces of teeth. Acts as a counter irritant and stimulates ab- sorption of effusions. What conditions about the mouth call for the use of carbolic acid, and what are its effects ? Full strength acts as a caustic and ma}^ be used to touch ulcers of gum tissue that has grown in a cavity. In a i% or 2% solution, as an astringent, antiseptic mouth wash in stomatitis. How should any injurious results arising from the local action of arsenic on the gums be treated ? Removing all necrotic tissue and touching with an iron preparation. Name the ingredients of a desirable dentifrice, and specify the properties that make each of these ingre= dients desirable. THERAPEUTICS AND MA TERIA MEDIC A, 189 Precipitated chalk gives body and is antacid. Orris root gives desirable degree of coarseness. Pnlverized sugar improves the taste. Boric acid gives antiseptic property. Flavoring substance improves the odor and taste. Name two preparations of opium. State the dose of eaeh. Tincture of opium or laudanum. Dose 5 to 15 minims . Camphoretted tincture of opium or paregoric. Dose 1 to 4 drachms. Of what drugs are morphine and atropine the alkaloids ? Opium and belladonna. Name a chemical antidote to bichloride of mer= cury ? Albumen. Name a physiologic antidote to cocaine. Morphine, whiskey, or nitrite of amyl. Name three different methods by which medi- cines may be administered ? By stomach, hypodermically, and through the rectum. For what is permanganate of potassium used in dentistry ? Ulcer of the mouth with offensive breath, ab- scesses, diseases of the antrum, necrosis and caries of bone. i go THERAPEUTICS AND MA TERIA MEDIC A. What are the dental uses of the essential oils ? To obtund hypersensitive dentine, to allay pain in an irritated pulp, to promote antisepsis in septic root canals and cavities. Describe the effect of aconite on the heart and name two other drugs which have a similar effect. Small doses decrease the force of ventricular contraction and slow the action of the heart. Large doses cause rapid weak action with tendency to stop in diastole. Veratrum viride and antimony have a similar effect. For what is amyl nitrite used, and how is it ad= ministered, and what is the dose ? Stimulant, particularly in cocaine poisoning. Usually administered by inhalation in three to five rninurn doses. What is the danger of using acids in the mouth ? What precaution should be taken ? They may cause disintegration of tooth struc- ture. They should be followed by antacid mouth washes For what is hydrogen peroxide used ? To destroy pus, to cleanse putrescent pulp canals, and whenever a germicide, deodorant or dis- infectant is required in the mouth. Name two escharotics, and state when escharotics should be used. Silver nitrate, carbolic acid. Escharotics are THERAPEUTICS AND MATERIA MEDICA- igi einplc^ed for the removal of hypertrophied gum tis- sue. To obtund hypersensitive dentine. In the treatment of ulcerative stomatitis, and to destroy pulp filaments in roots. riention three general and three local anesthetics. Nitrous oxide, ether and chloroform are general anesthetics. Hydrochlorate of cocaine, hydrochlorate of eucaine, and ethyl chloride are local anesthetics. What precautions should be observed in the ad= ministration of the general anesthetics ? Patients should not eat anything for several hours previous, should have bowels thoroughly evacuated, should be placed in a horizontal position, all foreign substances removed from the mouth, clothing loose around the neck and chest, a third party present if the patient be a female, and the anesthetic selected with reference to any organic disease of the patient. Development of dangerous symptoms should be watched for, and the anesthetic should not be given in an over dose. Resuscitating means should be at hand. Define hemostatic. Give three examples. Hemostatics are agents which stop hemorrhage by coagulating albumen and contracting the muscle fibres, e. g. tannic acid, tincture of iron, and nitrate of silver. ilention a medicine whose local action contracts the blood vessels of a part. Hydrochlorate of cocaine. 192 THERAPEUTICS AND MA TERIA MEDIC A. flention a medicine whose local action dilates the blood vessels of the part. Hydrochlorate of eucaine. Differentiate disinfectant from antiseptic. Give illustrations of each. Disinfectants are agents which destroy the germs of disease. Antiseptics inhibit the growth of micro- organisms and neutralize the toxins, but do not neces- sarily kill the germs. Permanganate of potassium {2% solution), bi-' chloride of mercury (1-1000), peroxide of hydrogen are disinfectants. Boric acid and the essential oils in mild solution act as antiseptics. What is the objection to the use of iodoform ? Mention three drugs that may be used in place of iodo= form. Its very objectionable odor. Iodol, aristol and europhaen may be used in place of iodoform. What is meant by the cataphoric application of a remedy ? The use of a very mild current for the purpose of forcing the remedy into the dentinal tissues. What is the advantage of the cataphoric as com= pared with the ordinary local application ? The deeper layers of the dentine and the pulp it- self may be affected, whereas the ordinary application could not be made to affect these. What two medicines are particularly useful in cataphoric applications ? THERAPEUTICS AND MA TERIA MEDICA- igj Cocaine hydrochlorate to desensitize dentine and pulp, and 25% pyrozone for bleaching. Mention (a) three remedies for toothache caused by exposure of the pulp ; (b) two remedies for perice= mentitis. (a) Oil of cloves, oil of cinnamon, carbolic acid. (b) Tincture of aconite and tincture of iodine. flention a remedy that antagonizes the consti= tutional action of aconite. A remedy that increases the constitutional action of aconite. Opium antagonizes the constitutional action of aconite, and veratrum viride increases the constitu- tional action of aconite. flention the dose of two of the preparations of opium, and the dose of one of the alkaloids of opium. Tincture of opium, 10 to 15 minims; powdered opium, V 2 to 2 grains; sulphate of morphine, ^ to J^ grain. flention the dose of (a) potassium bromide, (b) chloral, (c) acetanilid. (a) Potassium bromide, 10 to 40 grains; (b) chloral hydrate, 5 to 15 grains; (c) acetanilid 1 to 5 grains. Mention two heart stimulants that act rapidly, and give the dose of each. Aromatic spirits of ammonia 30-60 min. Ether 10-60 min. State the action of digitalis on (a) the heart, (b) the blood vessels, (c) the kidneys. (a) Increases the force of the heart contractions; 1 9 4 THERAPEUTICS AND MA TERIA MEDIC A. lengthens diastole, decreasing the number of beats by stimulation of the pneumogastric. (b) Raises arterial tension by stimulating vaso- motor centre, by direct action on the musular coat and by increasing the force of the heart's contraction. (c) Dilatation of the renal arteries resulting in an increased flow of urine, without an irritating effect on the renal epithelium. What drug is often combined with morphia when given hypodermically ? Explain. Sulphate of atropine. Atropine being the physi- ological antagonist, it diminishes the danger of mor- phia poisoning. Which of the general anesthetics is most depress= ing to (a) the circulation, (b) the respiration ? i Chloroform to the circulation, and ether to the respiration. What is an astringent ? Mention three vegetable and two mineral astringents. An astringent is an agent that causes contrac- tion of tissue. Tannic acid, sumac, and haematoxy- lon are vegetable astringents. Silver nitrate and zinc sulphate are mineral astringents. What is an escharotic ? An agent that destroys organic tissue when in contact with it. Give the indications for the use in producing sleep of (a) morphine, (b) chloral, (c) potassium bromide. Morphine is used to induce sleep when the pa- tient is suffering great pain. Chloral is given where THERAPEUTICS AND MA TERIA MEDICA. i 95 a patient is suffering from shock. Potassium bro- mide is given to allay nervous irritability, or as an aid to chloral hydrate. flention two medicines that increase blood pres= sure. Digitalis and strophanthus. Distinguish between a stimulant and an irritant. A stimulant produces increased functional activ- ity. An irritant exceeds the effect of a stimulant and induces venous hyperemia, and possibly inflammation. A stimulant acting continuously may become an ir- ritant. With what class of remedies are the coal tar pro= ducts prescribed for action on the heart? With cardiac stimulants. What is a sedative ? flention two sedatives. A sedative is an agent that lowers functional activity in a part. Aconite and gelsemium. What are the dental uses of the alkalies ? Men= tion two alkalies. To counteract any acid condition in the mouth, as in erosion or after acid medicaments. Lime, mag- nesium. What is the local action of chloroform when con= fined to a part so that evaporation is prevented ? Causes irritation resulting in the redness or even vesication with a sensation of heat followed by de- creased sensation of the part. What effect on blood pressure has (a) ether, (b) chloroform ? ip6 THERAPEUTICS AND MA TERIA MEDIC A. Ether increases blood pressure. Chloroform lowers blood pressure. State the dental uses of nitrate of silver. In the form of lunar caustic it may be used to destroy ulcers in the mouth, or to destroy hypersen- sitiveness of the dentine ; in about a 5 or even 10% solution, it is employed in gangrenous stomatitis. In 50% solutions it has been recommended in the treat- ment of root canals. State with reference to formaldehyde (a) its dental uses, (b) the advantages of its use, (c) the objections to its use. In mild solutions, in association with other agents, as an antiseptic mouth wash ; in strong solu- tions about 5 to 10% of formalin it is used to disin- fect instruments. In the treatment of moist gangrene of the pulp, and wherever a powerful disinfectant is indicated without regard to its intensely irritating effect upon mucous surfaces. It is a powerful disin- fectant, and has a hardening effect upon disintegrated organic matter. It is intensely irritating to mucous surfaces. Differentiate a decoction, an infusion, and a tincture. Decoctions are prepared by boiling vegetable substances in water. Infusions are vegetable sub- stances treated with hot or cold water without boiling. A tincture is an alcoholic solution of a drug. State the conditions under which it is more advan- tageous to give medicines hypodermically than to admin= ister them internally. THERAPEUTICS AND MA TERIA MEDIC A. i 9 y When }^ou wish to produce a quick effect. When the patient cannot swallow, or is in a condition where absorption from the stomach would take place slowly. Mention one drug that contracts the pupil of the eye; one drug that dilates the pupil of the eye. Eserine contracts ; belladonna dilates. What remedies, general or local, aside from opera= tive procedure are useful for relief of toothache, when (a) pulp is alive and not exposed, (b) pericementitis has super= vened on the death of the pulp ? For pulp pain we may apply the essential oils, carbolic acid, or some of the strong alkaloidal pre- parations. For pericementitis we make applications of aconite and tincture of iodine. Internally, we give combinations of acetanilid and phenacetin ; and, in very severe cases, opium or chloral combined with ammonium bromide. State the reasons for or against the use of arse= nous acid to obtund sensitive dentine. It should not be used to obtund hypersensitive dentine, as it will devitalize the pulp. Mention the contraindications of chloroform anes= thesia. Chloroform should not be used where the recum- bent position cannot be maintained, or in any serious form of cardiac lesion. Describe the methods of administering cocaine to produce anesthesia. Anesthesia of the dentine and pulp may be in- duced by 10% or 15% solution of cocaine, forced into ig8 THE RAPE UTICS A ND MA TERIA MEDIC A. these tissues by pressure, or trie cataphoric current. Hypodermic injections are made with a i or 2% solu- tion for purposes of extraction. Of what is each of the following an alkaloid (a) strychnine, (b) atropine, (c) morphine. State the dose of each. (a) Nux vomica, (b) belladonna, (c) opium. Strychnia, fo- 2 T gr.; atropine, t x so -'f s gr.; mor- phia y*-y 2 gr. What property of tincture of iodine makes it of value in pericementitis ? Its counterirritating property, and its ability to stimulate the lymphatics to absorb inflammatory pro- ducts. In what position should the patient be during the administration of chloroform ? Why ? In the recumbent position, to allow of the easy flow of blood to the heart, to counteract the paralyz- ing influences of chloroform upon the circulation. Name four properties that a dentifrice should possess. Alkalinity, antiseptic property, sufiiciently coarse to be cleansing, and agreeableness to taste. What is an antiphlogistic? Any therapeutic means of combating the heat of inflammatory reactions. What is an escharotic ? An agent which devitalizes the tissue upon which it acts, producing an eschar or slough. THERAPEUTICS AND MATERIA MEDIC A. ig 9 Name a condition about the mouth calling for the use of an escharotic. Name the escharotic best suited for the purpose. In ulcerative stomatitis nitrate of silver is em- ployed with most satisfactory results. What medicaments are useful in the local treat= ment of pyorrhea alveolaris, and what is accomplished by them ? Peroxide of hydrogen to destroy pus, and the pus forming organisms. Sulphuric acid dilute, or lactic acid concentrated for aids in removal of concre- tions upon roots. Trichloracetic acid in about 10% or even 20% solution, as a powerful antiseptic and astringent application in pockets. Define anesthetics, narcotics and sedatives and give an example of each. Anesthetics are agents that are capable of over- whelming the nervous centres, thus interfering with perceptions of pain, as ether or chloroform. Narcotics are agents that stimulate and stupefy the brain, allay pain and induce sleep, as opium. Sedatives are agents that depress the nervous centres and allay their ir- ritability or excitability, as bromide of potassium. Describe what is meant by an aqueous solution, and write a prescription, giving example. An aqueous solution is a drug held in a solution of water. Jfy Acidi Tannici, gr. x Aquae, f§ j 200 THE RAPE UTICS A ND MA TERIA MEDIC A. Give rule for finding the amount of a drug in a given percentage of solution, with example. 4% grs. to i oz. of solution being a 1% solu- tion, therefore, if we have the percentage we multiply it by 4J/2 , and the result is the amount of the drug in the given percentage. If we speak of a 5% solution we know that approximately we have 4% times 5, or 22% grs. for every oz. Differentiate fixed oils and volatile oils, and give three examples of each. The fixed oils are compounds of carbon, hydro- gen and oxygen; the volatile oils are composed of car- bon and hydrogen. Among the fixed oils we have castor oil, almond oil, olive oil. Of the volatile oils we have cloves, cinnamon, peppermint. What is hydrogen dioxide ? Give its formula and dental use?. Certain volumes of oxygen mechanical ly held in water, H 2 2 . Hydrogen dioxide is used to de- stroy pus in alveolar abscess, or pyorrhea pockets, to cleanse putrescent root canals, and wherever a non- toxic disinfectant is indicated. What is arsenous acid ? Give medical properties and special dental use and antidote, Trioxide of arsenic. Internally, in small doses, it acts as an alterative tonic, promoting appetite and digestion, stimulating respiration and circulation, and increasing mental faculties. In dentistry, it is em- ployed to devitalize the pulp. The antidote in cases of poisoning is freshly prepared hydrated ferric oxide. THE RAPE [/TICS AND MA TERIA MEDIC A . 201 What is iodoform ? Give a solvent and dental uses. Iodoform is the result of the action of iodine on alcohol and potassium hydroxid; the symbol being CHI 3 . Alcohol is a solvent. In dentistry, it is mostly employed as a filling in pulpless canals and in the form of iodoform gauze for packing wounds, but its odor is a serious objection to its employment. Give the medical properties and dose ; when indi= cated in dental practice, and how used ; toxic effects, if any; antidotal treatment of each of the following: — Aco= nite, quinine, naphthol, creasote, oil of cloves. Aconite locally paralyzes the terminal sensory filaments, causing numbness and loss of sensibility. Internally, in small doses it depresses respiration and circulation, and in large doses it paralyzes the heart's action. In dental practice it may be used locally to stop pain from an irritated pulp, or as a sedative ap- plied over the gum in pericementitis. Opium, or an}^ cardiac stimulant, together with artificial respiration are used in cases of poisoning. The dose is 1-3 min- ims of the tincture. Quinine is a tonic, antiseptic, antipyretic and antiperiodic. It interferes with the functions of the red blood corpuscles and arrests the movements of the white. In small doses it stimulates the brain; in large doses, it produces cerebral anemia, ringing in the ears, headache, delirium and coma. The tonic dose is 2 grs.,the antipyretic 5-10 grs., and the anti- periodic 10-20 grs. Morphine antagonizes its cere- bral action. Atropine its cardiac and antipyretic ef- 202 THERA PE UTICS A ND MA TERIA MEDIC A* fects. Its use in dentistry is indicated when a patient gives evidence of septic fever through absorption of septic products in cases of acute septic pericementitis or alveolar abscess; in combination with acetanilid and salol, two grains of the sulphate of quinine given every two or three hours will have a controlling effect. Naphthol is a derivative of naphthalin, and has marked antiseptic properties. In dentistry it is used as hydronaphthol, a powerful antiseptic in 1-200 solution. Creasote locally acts as an escharotic. Internally in small doses, its action is similar to carbolic acid. It is eliminated by the bronchial mucous membrane, which it stimulates, producing the effects of an ex- pectorant. It is sedative to the mucous membrane of the stomach. In dentistry, it is indicated wherever carbolic acid is used, although the latter is favored because it has not the intensely disagreeable odor of creasote. Dose 1-3 minims in oil. Oil of cloves belongs to a group of aromatic oils that possess many properties, in general. They are antiseptics, stimulants, and local anesthetics. Dose 1-5 minims. In dentistry, it is used generally to allay pain in an aching pulp. What is formaldehyde ? State dental uses and strength of solution that should be used for each purpose. It is prepared by burning methylic alcohol in the presence of oxygen forming an oxide. It is used in the mouth as an antiseptic in % of one % solu- THERAPEUTICS AND MA TERIA MEDICA 203 tion. In gangrenous pulp canals it is used in about 10% solutions. Write two complete prescriptions, one containing a drug in aqueous solution, and the other containing a drug insoluble in water, also in solution. 1^ Plumbi acetatis, gr. v. Aquae dist., f5j. ]jk Hydronaphthol, 5j- Alcohol, f"5j. Sig. Teaspoonful in wineglass of water. Name three drugs useful in the treatment of em= pyema of antrum, and write a prescription containing one such drug in solution. Hydrogen dioxide, chloride of zinc, hydrona- phthol. 1^ Hydronaphthol, 5j- Alcohol. fjj. Sig. Teaspoonful in wineglass of water. Name three heart stimulants administered hypo= dermically in the order of their rapidity of action. State dose of each. Alcohol, strychnia, digitalis. .Alcohol (whiskey), 30-60 min. Strychnia sulphate, 60-20 gr. Digitalis (tincture), 5-10 minims. Name two drugs useful in failure of respiration under anesthesia, state dose, and how administered. Strychnine, 2 Z Q gr., and atropine, ^ gr. Adminis- tered hypodermically. Define styptic, irritant and astringent, and give an example of each. A styptic is an agent applied locally to check 204- THERAPEUTICS AND MA TERIA MEDICA. hemorrhage, like tannic acid. An irritant is an agent capable of drawing an excess of blood to the part upon which it is acting, like iodine. An astrin- gent causes contraction of living tissue, e. g. krameria. Name two drugs that are physiologically incom= patible, and two that are chemically incompatible. Aconite and morphine ; belladonna and opium, are physiologically incompatible. Tannic acid and iron ; sulphuric acid and lime, are chemically incom- patible. Give the dental uses of oil of cinnamon, silver nitrate, aconite, capsicum. Oil of cinnamon is used to allay an irritated pulp, or as an antiseptic application in root canals. Silver nitrate may be used in the form of lunar caus- tic to touch ulcers appearing in the mouth, or in full strength to obtund hypersensitive dentine. It has also been recommended, in 50% solution, in the treat- ment of pulpless canals. Tincture of aconite is used as a sedative application in pericementitis ; also, to control an aching pulp, and as an ingredient of oint- ments in neuralgia. Capsicum is used as an irritant in pericementitis, and as a stimulating ingredient in mouth washes in relaxed conditions of the mucous membrane. What are fluid extracts ? Alcoholic solutions, one minim representing one grain of the crude drug. How is the muscular system affected in complete anesthesia under ether and under nitrous oxide ? THERAPEUTICS AND MA TERIA MEDIC A. 2oj Under ether the muscles are relaxed. Under nitrous oxide the muscles are contracted. What are the advantages and disadvantages in the use of chloroform as an anesthetic in tooth extraction ? State symptoms of danger and treatment in case of collapse. The anesthesia resulting from inhalations of chloroform is prolonged, affording free opportunity for the removal of any number of teeth. The disad- vantages are decided. The upright position is against the patient; and, furthermore, failure of the heart's ac- tion is apt to result in consequence of the irritation of the puenmogastric induced through irritation of the fifth pair of nerves in the extraction. Symptoms of danger under chloroform are generally in relation to the heart's action. Failure of respiration would in- dicate danger, or sudden dilatation of the pupil of the eye. In collapse, raise the lower extremities and give an injection of strychnia and atropine. Emplo}^ artificial respiration, and warm applications to the body. What is ethyl chlorfde ? Describe method of pro= ducing local anesthesia by its use, and state precau- tions to be observed. Ethyl chloride is a volatile substance with a boiling point of about 60 ° F. When a spray is directed against tissue it acts as a freezing mixture by its very rapid volatilization. The tissue not to be affected should be protected against the spray. By the use of cold applications the tissue may be pre- vented from too quickly returning to a normal state, 206 THE RAPE UTICS A ND MA TERIA MEDIC A. and thus lessen the incident pain which is usually felt after the use of chloride of ethyl. Describe the three stages of anesthesia under ether. In the first stage we have irritation in the fauces and coughing, followed by the second stage of cerebral intoxication, followed by the third stage of anesthe- sia, in which the face is usually flushed, full and regu- lar breathing, reflexes of the eye abolished, and muscles completely relaxed. Give the physiological action of nitrous oxide. It is a stimulating narcotic and anesthetic, with asphyxiating features. Give the precautions to be observed before and during the administration of nitrous oxide. The patient should be examined as to physical condition, and also as to what teeth or roots are to be extracted, so that no time is lost later. Care should be taken that sufficient nitrous oxide is at hand for the operation, and a third party should be present. The jaws should be kept separated. During the admin- istration, the respiration should be carefully watched. Interference with respiration is the chief source of dan- ger. As soon as the anesthetic state is induced, further administration should at once cease. Describe fully two methods for producing local anesthesia. Hypodermically, with a \% or 2%solution of cocaine hydrochlorate, injecting about 20 minims of the \% or 10 minims of the 2% solution about the alveolar tissue; or by means of a spray of ethyl chlor- ide, protecting the tissues not to be affected. The THERAPEUTICS AND MATERIA MEDIC A. 207 spray is directed until the tissues whiten. It is also better not to allow of a too rapid return to normal con- dition of the anesthetized parts. This may be pro- duced by directing the patient to hold cold water in the mouth. Give conditions in which anesthesia is contra= indicated. When the patient is suffering from shock after an accident, and in serious organic cardiac lesions, like fatty degeneration or dilatation; or, where seri- ous interference with respiration is noted. Patients suffering from renal diseases, should not be given ether. Describe methods of procedure and precautions necessary in hypodermic injections for producing local anesthesia. The parts to be operated upon should be treated antiseptically, so that no adherent septic matter is carried into the subtissues. The needle should be as clean as it is possible to make it. Care should be taken not to penetrate a blood vessel. After injection the fluid should not be allowed to escape. The proper quantity and no more should be injected. How is anesthesia modified by age, sex and tem= perament ? In children we find a ready response to the in- halation of anesthetics. When ether is used, a hy- persensitive mucous surface in the pharynx and larynx induces coughing; in the aged, chronic bronchial irri- tation is apt to produce the same result. Women are 208 THE RAPE UTICS AND MA TERIA MEDIC A. apt to give manifestations of hysterical tendencies. Sex and temperament may influence the amount nec- essary to induce anesthesia. The stage of excite- ment may be prolonged in hysterical subjects, and also in those of bilious attributes. What anesthetic do you prefer, and for what reason ? For the extraction of teeth and minor operations in the mouth that require little time for their execu- tion, nitrous oxide is the safest anesthetic we have at the present time. From a most extended experience during which hundreds of thousands of patients have been placed under its influence, the death rate is prac- tically nil. Mention some of the organic lesions which contra* indicate the administration of anesthetics. Fatty degeneration, dilatation and valvular diseases of the heart. In patients with tendency to apoplexy. Renal complications. Serious interferences with respiration. These conditions either set aside the use of anesthetics, or make their use dangerous. flention the differences between cocaine and eucaine. Cocaine is an alkaloid, soluble to the extent of over 30% in water, disintegrates upon boiling, and frequently is followed by poisonous symptoms. Eu- caine is synthetically prepared; is soluble to the extent only of about 4% in water, does not disintegrate when subjected to heat, and its use is not so frequently fol- lowed by dangerous symptoms. THE RAPE UTICS AND MA TERIA MEDIC A. 209 At what period in nitrous oxide anesthesia may you have failure in circulation ? After the anesthetic stage, owing to the anemia of the brain. What causes the darkened appearance of the pa= tient under nitrous oxide, and state in what manner this may be lessened. The accumulation of carbon dioxide. Giving oxygen in combination with nitrous oxide will con- siderably lessen the bluish appearance of the coun- tenance. From what is nitrous oxide prepared ? From nitrate of ammonium, effecting its decom- position through heat. What is liquid nitrous oxide ? The gas nitrous oxide liquefies when subjected to a pressure of about 700 pounds at a temperature of about 45 F. From what is ether prepared ? Through the action of sulphuric acid upon ethy- lic alcohol. What is the appearance of the face under ether an= esthesia ? What is its effect upon the muscular system ? Generally flushed. It causes relaxation of the muscular system. What appliances should be at hand and in readi- ness when anesthetics are used ? Hypodermic syringe, with various respiratory and circulatory stimulants. Also the facility to perform artificial respiration. 210 THERAPEUTICS AND MA TERIA MEDIC A. What is bromide of ethyl ? An anesthetic agent prepared from bromide of potassium, sulphuric acid and ethylic alcohol. How is it administered, and what is its action ? The quantity to be administered is poured out upon a towel (about 2 drachms) and inhaled by the patient. Bromide of ethyl resembles chloroform in its action upon the heart. It interferes with the function of the red corpuscles, and affects conscious- ness last ; in many cases patients are conscious and yet not perceptive of any pain. The anesthesia generally lasts about five minutes. What strength of solution of cocaine would you employ for hypodermic use, and how much of the solution would you use ? Generally 1% or 2% solution is employed. 20 minims of the 1%, or about 10 minims of the 2% solu- tion may be injected. Give the antidote of the following drugs, (a) iodine, (b) bichloride of mercury, (c) arsenic, (d) phos= phorus. (a) Starch, (b) albumen, (c) hydrated ferric oxide (freshly prepared), (d) turpentine. Mention two drugs insoluble in water. Bismuth, chloride of mercury (mild). What alkaloids are found in opium ? What is its active principle ? Morphine, codein, narcotine, thebaine. The active principle is morphine. THE RAPE UTICS A ND MA TERIA MEDIC A. 211 What is meant by a mydriatic ? Name one. A mydriatic is an agent which causes dilatation of the pupil of the eye, e. g. belladonna. What is meant by a synergist ? Name the syner- gists of aconite. A synergist signifies an aid. Veratrum viride, tartar emetic or bromide of potassium act as syn- ergists to aconite. What is a cathartic, and how are cathartics divided ? Cathartics are agents which produce evacuation from the intestinal tract. They may be arranged according to the severity of the effect. Laxatives are the mildest, purgatives are more severe, and drastics most severe in their action. Give the treatment of poisoning from cocaine. Fresh air, inhalations of nitrite of amyl or am- monia. Alcohol, (brandy or whiskey), aromatic spirits of ammonia, strychnine, digitalis and atro- pine, hypodermically or by the mouth. External heat. State the local action of cocaine on the blood vessels. Cocaine applied to a mucous membrane or in- jected under the skin causes the blood vessels of the part to contract. As the effect passes off, the reaction results in dilatation. Name three mineral acids employed in dentistry and give their properties and uses of each. 212 THERAPEUTICS AND MA TERIA MEDIC A. Hydrochloric acid. — The strong acid is a power- ful caustic and escharotic ; also disinfectant and furni- gant. The dilute acid is tonic, refrigerant and astringent. The strong acid is employed as a local applica- tion in gangrenous stomatitis, or cancrum oris, for arresting the ulcerative process. Combined with equal parts of glycerine it is useful in inflammation and ulceration of the oral mucous membrane ; also in cases of sloughing. In aphthous ulceration of the mouths of children, it is often useful. Nitric Acid. — Pure nitric acid is a powerful caus- tic and escharotic. The dilute acid is an antalkaline, alterative tonic and refrigerant. The strong acid, when mixed with two parts of hydrochloric acid, is solvent for gold. It is employed as a caustic in cancrum oris ; also for malignant ulcers of the mouth and for devitalizing pulp of teeth when nearly exposed by mechanical abrasion. Sulphuric acid. — The strong acid is a powerful escharotic, the dilute acid is refrigerant, astringent and tonic. The concentrated sulphuric acid is used as a caustic in malignant ulcers, cancrum oris and gangrene in the form of a paste, made by mixing it with powdered sulphate of zinc. It is also used to cleanse metal plates. The dilute acid or the aromatic sulphuric acid which is more agreeable is used in pyorrhoea alveolaris, and in caries and necrosis of the maxillary bones, as an injection or lotion. It is also employed in cases of recession of the gums and ab- THERAPEUTICS AND MATERIA MEDIC A- 2i 3 sorption of the processes. It is valuable in alveolar abscesses as an injection. It is employed in stoma- titis and ulcers of the mouth. Mention (a) two heart stimulants, (b) two heart sedatives. State the dose of each. (A) Aromatic Spirits of Ammonia, 20 minims to 1 drachm. Whiskey, 2 drachms to 1 ounce. (B) Tincture of aconite, 1 to 5 minims. Tincture of veratrum viride, 3 to 30 minims. Mention three medicines used to produce emesis and state how each is administered. Sulphate of zinc, 10-30 grs. by mouth. Sulphate of copper, 2-4 grs. by mouth. Apomorphine hydrochlorate, le-^i g r - hypo- dermically. flention three medicines used to produce diapho- resis. Pilocarpine, tartar emetic and Dover's powder. What is the local action of chloroform ? Placed on the skin and allowed to evaporate it produces a sensation of cold. If the vapor be con- fined it causes irritation with redness and even vesi- cation accompanied by a sensation of heat followed by numbness and a decreased sensation of the part. Define materia medica, therapeutics. Materia medica treats of the source of drugs, their physical and chemical properties and may also include their physiological action. 2i 4 THE RAPE UTICS AND MA TERIA MED/CA. Therapeutics treats of the application of remedial agents to disease. In what ways may medicines enter the system ? Mouth, rectum, respiratory tract, absorbed through the skin and injected under the skin. What is the difference in the source of carbolic acid and creosote ? Carbolic acid is obtained during the distillation of coal tar. Creosote is obtained during the distilla- tion of wood tar. Name two drugs whose poisonous action is mark= edly manifest in the mouth. Give the distinguishing characteristics of the effects of these drugs. Iodides and mercury. Iodism is manifest by swelling and redness of the gums, fauces hard and soft palate, foulness of the tongue, fetid breath, and increase of mucus in the mouth; also headache, coryza and increased bron- chial secretion. Mercury may increase the salivary flow to several pints per day. At first the secretion is thick but later becomes thin. Fetid breath, sore gums may go on to ulceration of the mouth and cheeks. Low fever. Which of the vital organs fails first in collapse from (a) ether, (b) chloroform ? (a) Kills by paralysis of respiratory center (b) usually the heart, but may be respiratory center. Name two medicines that decrease blood pressure. Tartar emetic and tincture of aconite. THERAPEUTICS AND MA TERIA MEDIC A. 21 5 Describe the method of administering a medicine by which its quickest action is obtained. The medicine in solution is placed in a hypoder- mic syringe (the syringe and solution being as near aseptic as possible). The air is expelled while the needle points upward, sterilize the skin and inject con- tents into the cellular tissue. Define diuretic, diaphoretic, expectorant. Diuretics are agents which increase the flow of urine. Diaphoretics increase the perspiration. Ex- pectorants increase and modify the secretion of the bronchial mucous membrane. Differentiate a tonic and a stimulant. Tonics promote secretion and give tone to the s} T s- tem. Stimulants increase the function of the part or organ. Mention two medicines that may be used as cauteries. Nitrate of silver and carbolic acid. State the treatment of carbolic acid poisoning. Administer a soluble sulphate (sodium or mag- nesium) and follow by albumen and mucilaginous drinks. Wash out the stomach. Combat collapse by external heat and with hypodermic injections of strychnine and atropine. What is an emetic ? Emetics are agents which excite vomiting either by local or central action. 216 THERA PE UTICS A VD MA TERIA MEDIC A* flention two drugs that reduce fever. Acetanilid. Quinine. What is an analgesic ? An agent which relieves pain. This may be accomplished either by local or central action. Describe the symptoms of cocaine poisoning. A rapid feeble and irregular pulse, with shallow and labored respiration, clammy skin, dilated pupils, delirium and hallucinations. May have clonic con- vulsions and increased temperature. What restoratives are most desirable in case of threatened collapse during the administration of (a) Ni= trous Oxide, (b) Ether, (c) Chloroform. (a) Amyl nitrite, oxygen, atropine. (b) Ammonia, oxygen, strychnine, atropine and farradic current. (c) Ammonia, strychnine and digitalis. What is the antidote for opium ? Potassium permanganate (chemical). Atropine (physiological). What is the dose of bichloride of mercury ? Give its antidote. (kr-il gr. Antidote, albumen. flention two purposes for which medicines may be applied cataphorically in dentistry. For painless tooth extraction, and to antisep- ticize pulp canals. THERAPEUTICS AND MATERIA MEDIC A. 21 7 What medicines are indicated and about how long should they be applied cataphorically for the purposes mentioned in the preceding question. (a) Cocaine, (b) Silver Nitrate, 8-20 minutes. Hention three saline cathartics and state the dose of each. Sulphate of magnesia (Epsum salt), 1 drachm to iY 2 ounces. Tartrate of Potassium and Sodium (Rochelle salt), 1 drachm to 1 ounce. Solution of Citrate of Magnesia, 12 ounces. Distinguish between narcotics and hypnotics. Narcotics stupefy and weaken vital actions. Hypnotics produce sleep. Mention three good counterirritants. Cantharides, croton oil, and mustard. Define chemical antidote for a poison, physiologi= cal antidote for a poison. By chemical antidote is meant some substance which combines chemically with the poison produc- ing an inert or insoluble compound. By physiologi- cal antidote is meant a substance which is opposed to the poison in its action on the economy. Mention the source of carbolic acid. State three properties of carbolic acid. Coal tar. Local anesthetic, caustic and antiseptic. Name the antacids valuable for use in the mouth. 218 THERAPEUTICS AND MA TERIA MEDICA, Sodium bicarbonate, lime water, chalk and char- coal. What is the chief use of capsicum in dentistry ? As tincture or plaster in periodontitis. Name a condition about the mouth calling for the use of an escharotic. Name the escharotic best suited for the purpose. Cancrnm Oris. Carbolic Acid. What is meant by chemical and physiological in= compatibility of medicines ? Agents are said to be chemically incompatible when their mixture results in the decomposition of one or more of the ingredients. Physiological incompatibility is where one drug produces effects upon the system opposite to the action of some other drug, like aconite and opium. Give the physiological action of belladonna. Belladonna is an anodyne, an anti-spasmodic, a mydriatic, an irritant narcotic ; in small doses a resp- iratory, cardiac, and spinal stimulant; in large doses a paralyser of the secretory and motor nerve endings, and a stimulant of the sympathetic system. It pro- duces dryness of the mucous membranes of the nose, mouth, throat and larynx; and at first lessens the gastric and intestinal secretions, but soon reproduces them in large quantity. The heart-rate is at first slowed, but soon becomes vigorous and rapid. Give the mouth signs of mercurial poisoning. THE RAPE UTICS A ND MA TERIA MEDIC A, 219 Hyperemic mucous surface, teeth tender upon pressure and loose, increased flow of saliva, swollen tongue, and metallic taste. How should the administration of chloroform dif- fer from that of ether ? Chloroform should be administered a few drops at a time and the vapor allowed to mix freely with air while ether is administered in larger quantities and only a small amount of air allowed to mix with the vapor. flention the contraindications of ether anes- thesia. In cases where interference with respiration ex- ists. In affections of the kidneys. In plethoric indi- viduals with tendency to apoplexy. In abdominal operation where subsequent wretching or coughing would disturb the womb. State the objection to the use of iron salts, as styptics. The clot which is formed is soluble in the fluids of the mouth, frequently resulting in secondary hemorrhage. What drug is given hypodermically to produce emesis ? State the dose of this drug. Hydrochlorate of apomorphine, ^ to \ of a grain. flention, with doses, three coal tar preparations, useful in the treatment of neuralgia. Acetanilid, 2-5 grs.; phenacetin, 2-5 grains; an- tipyrine, 5-10 grs. 220 THERAPEUTICS AND MA TERIA MEDIC A. Differentiate poisoning by atropine and poisoning by strychnine. In atropine poisoning we have motor paralysis, delirium and death. In strychnine poisoning we have convulsive action of the muscles with consciousness. Mention three disinfectants suitable for use in pu= trescent root canals of teeth. Hydrogen dioxide, formalin, carbolic acid. What are the contraindications for the use of nitrous oxide ? In cases with marked interference with respira- tion. Write a prescription for an antiseptic mouth wash. R> Acidi carbolici (95%) mxxx. Aquae q. s. f.^v. Sig. Use as mouth wash. What is meant by the active principles of a drug ? Give an example. The extractive substance which gives the drug its medicinal properties. Quinine is an active prin- ciple of cinchona bark. Mention three alteratives. Arsenic, mercury and iodine. Give the physiological action of Ergot. Externally it acts as a slight astringent on the broken skin or mucous membrane. Gastro intestinal tract. — Disagreeble taste and may produce nausea and vomiting. THERAPEUTICS AND MATERIA MEDIC A- 221 Circulation. — Heart-beat becomes slow and in- creased in force. It stimulates the vasomotor cen- tre and unstriped muscular fibres of arteries raising blood pressure. Uterus. — It stimulates the contraction of the parturient uterus, increasing the force and frequency. There is a marked decrease in the blood supply of the nonparturient uterus. Nervous system.— It causes anaemia of the cen- tres, particularly in the spinal cord. Give the physiological action of digatalis. Gastrointestinal tract. — Digitalis may cause nausea, vomiting and diarrhoea. Circulation — Decreases the number of heart beats, lengthening diastole (stimulation of inhibitory fibres of vagus). It increases the force of the con- tractions (intrinsic ganglia). Arterial tension rises from increased cardiac force, excitation of vasomotor centre, and direct action on the muscular coats of the arteries. Kidneys. — Followed by relaxation of renal ar- teries resulting in an increased flow of urine. Later the heart becomes weak and irregular, beating with increased frequency. Large doses decrease abnormal temperature. It may cause headache, vertigo or de- lirium. It also stimulates the uterine contractions. Give the physiological action of nux vomica Gastrointestinal tract.— Small doses act as a bitter tonic increasing appetite, secretion and diges- 222 THERAPEUTICS AND MA TERIA MEDIC A . tion. It increases the muscular tone of the stomach and peristalsis is also increased. Circulation. — Cardiac centre, vaso motor centre and cardiac ganglia are stimulated raising arterial tension increasing the force of heart action but slow- ing its beat. The respiration centre is stimulated, the pupils dilate, the contractile power of the bladder is stimulated, the reflex activity of the spinal cord is increased. It also acts as an aphrodisiac. Give the physiological action of Opium. Externally it is slightly sedative. Stomach. — It decreases sensation, secretion and peristalsis, reducing hunger and pain. Continued use deranges digestion. Intestines. — Sedative action, relieving pain, se- cretion decreased and peristalsis is decreased by stimu- lation of the splanchnics (inhibitory nerves.) Large doses may cause diarrhoea leading to paralysis of the splanchnics. Bile and pancreatic juice are de- creased. Nervous System. — The convolutions of the brain are briefly excited, then depressed by direct action on nerve cells (possibly by causing anemia). Stage of Excitement. — Exaltation of feelings, happiness, brilliancy of imagination, increase of in- tellectual power and mental vigor. Imagination becomes extravagant, dreams of grotesque and im- possible things. Sensory and perceptive centres be- come depressed, stupor and sleep. Pupil of the eye is contracted. THERA PE [/TICS A ND MA TERIA MEDIC A . 223 Spinal Cord.— Reflex activity is increased due to stimulation of centres, followed Ity depression and decreased reflexes. Medulla. --The respiratory centre is slightly stimulated then depressed, respiration becoming slow; it kills by paralysis of respiratory centre. The cardiac centre is stimulated and the heart beats slowly and strongly, depression being late. The sensory nerve endings are depressed. Give the toxic symptoms of opium. Coma from which the patient cannot be aroused. The reflexes are abolished, skin moist and cyanotic, pulse weak, respiration slow and labored (five to six in a minute) pupils contracted (pin point) but may dilate just before death. Muscles are relaxed. Death is caused by paralysis of the respiratory centre. Give the toxic symptoms of nux vomica. The patient becomes restless with muscular twitching and a sensation of impending suffocation. Suddenly the patient is seized with a violent clonic convulsion which pervades the whole body (particu- larly the extensor muscles). The face is drawn, opisthotonos supervines, the eyes are prominent, pupils dilated, face is livid and congested, due to spasms of the- respiratory muscles. The intellect remains clear. The spasms are intermittent, lasting from one half to five minutes. Death results from accumulation of CO,. CHEMISTRY AND METALLURGY. What is water of crystallization ? Water of crystallization is such water in solid form as gives to a substance its crystalline shape and frequently its color. Give two methods of obtaining hydrogen ? (i) By the action of zinc on sulphuric acid. (2) By the electrolytic decomposition of water. What conditions are essential for the perfect weld= ing of metals, whether hot or cold ? Perfect cleanliness. Freedom from oxidation. Application of considerable compressing force. Selection of the proper metals. Give the chemical formula of bicarbonate of soda. NaHC0 3 What chemical change occurs in the action of H 2 2 as a germicide or antiseptic? H, 2 is changed into water and nascent oxygen in contact with organic matter. What properties does platinum impart to its alloy with gold ? Elasticity. Greater strength. Greater hardness. It gives a white color. How would you distinguish a bar, or plate, of tin from a metal similar in appearance ? CHEMISTRY AND METALLURGY. 225 By bending it, tin evolves a peculiar sound known as the - " tin cry." This is only evolved when the tin is quite pure. Name some of the purer forms of carbon as found in nature. Diamond and graphite. Define separately the terms Ductility, Mallea= bility and Volatility, and give examples of each. Ductility is that property of matter by virtue of which it may be drawn into wire, e. g. gold, silver, platinum. Malleability is that property of matter by virtue of which it may be hammered into sheets, e. g. gold, copper, and tin. Volatility is the readiness with which a metal passes into vapor with or without heat, e. g. mer- cury, zinc, tin. Give approximately the composition of Brass and German Silver. Copper 50 to 60 ] Zinc 20 to 30 y form German Silver. Nickel 10 to 20 J Brass is an alloy of zinc and copper ; the addi- tion of nickel forming German silver. In uniting platinum to platinum, what would you use as a solder, and why ? Gold, because it readily alloys with platinum, giving a strong, permanent union and a color like that of platinum. Place after each of the following metals, its chem= ical symbol : Gold, Platinum, Silver, Tin and Copper. Gold, Au.; Platinum, Pt; Silver, Ag.; Tin, Sn.; Copper, Cu. 226 CHEMISTR Y AND ME TALL URGY. Describe the simplest test for Sodium and Potas= sium Salts in solution. Wet a clean platinum wire in trie solution and hold in the inner Bunsen flame ; the outer flarne would be colored yellow if sodium, and violet if potas- sium be present. It may be necessary to concentrate the solution. Give a chemical test for Silver in solution. The addition of hydrochloric acid, or a soluble chloride, produces a white precipitate of chloride of silver, soluble in ammonium hydrate, but insoluble in nitric acid. Give the formula of Acetic Acid, Oxalic Acid. Acetic Acid, HC 2 H 3 2 . Oxalic Acid, H 2 C,0 4 . Define the term Amalgam. Amalgam is an alloy of two or more metals, one of which is mercury. Describe the methods of tempering steel instru= ments. The instrument is placed in a sand bath and covered with sand, leaving a minute point exposed to the air ; heat is then gradually applied to the sand bath until the desired temperature of steel has been reached, which can be told by the color of the ex- posed part. The instrument is then cooled quickly, as by immersing in water, acids or other liquids. Various methods of heating are used as hot lead, alcohol lamp, open fire. What are the advantages of annealing alloys for dental amalgam ? Describe the process. CHE MIS TR Y AND MET AIL UR G V. 227 To reduce brittleness. At times, to change the character of the alloy and to secure uniformity of the alloy. The substances are heated and then allowed to slowly cool, the process being the inverse of tem- pering. What elements constitute the chlorine group ? Are they metallic or nonmetallic ? Chlorine, Bromine, Iodine, Fluorine. Nonmetallic. Write the chemical formula for Potassium Iodide, Zinc Chloride and Calcium Sulphate. Potassium Iodide, KI. Zinc Chloride, Zn Cl 2 . Calcium Sulphate, CaS0 4 . What chemical changes result from the addition of Hydrochloric Acid to Silver Nitrate ? Answer by giving the equation. AgN03+HCl=AgCl f HNO3. Give two methods of obtaining oxygen. The oxides of the noble metals are by heat de- composed into the metal and oxygen. HgO+heat =Hg+0. Potassium chlorate, KCIO^, may be decomposed by heat into potassium chloride, KC1, and oxygen. KC10 3 +heat=KClH-30. What are the chemical and physical properties of asbestos ? Asbestos is a silicate of magnesium. It occurs in mineral deposits in silky like fibres and ma}' be 228 CHE MIS TR Y AND ME TALL UR G Y. woven into cloth. It is not dissolved or affected by water, acids, or heat. Name four organic acids. Acetic, citric, lactic, butyric. What metals and alloys are used for dies and counter=dies ? State for which each is best adapted. Zinc ; Babbitts metal ; alloy of zinc and tin. Zinc ; lead. Babbitts metal is used where tissues covering hard palate are thick and spongy while alveolar ridge is hard and covered by a thin membrane. For other purposes zinc is better for dies. In counter-dies zinc is serviceable in working platinum-gold or iridium-platinum. For more perfectly swaging the metal to the die, zinc is also of great assistance in conforming plates to dies for partial dentures. For other pur- poses lead is used. Name five metals all of which can be manufac= tured into wire, sheets, or foil. Gold, platinum, silver, copper, tin. Name some'of the metals for which mercury pos= sesses a great affinity. Silver, tin, sodium. What are the principal differences between metal= lie and nonmetallic elements ? A metallic substance is solid at ordinary tem- peratures, with few exceptions. Has considerable weight and is more or less malleable, ductile and CHEMISTR Y AND METALL URGY. 229 tenacious. It is opaque to light and is a good con- ductor of heat and electricity. It has a lustre, is electro-positive and forms bases with oxygen. It dis- places hydrogen from acids to form salts. Substances not possessing these characteristics are grouped as non-metals. Place the chemical formula after each of the fol- lowing acids : Sulphuric, Nitric, Hydrochloric. Sulphuric, H 2 S0 4 . Nitric, HNO3. Hydrochloric, HC1. How does plaster=of= Paris differ chemically from quick=lime ? Quick-lime is oxide of calcium, CaO. Plaster-of-Paris is dehydrated sulphate of calcium, 3CaS0 4 . 2H 2 0. (Bloxhain). What constitutes the difference between a noble and a base metal ? Give examples of each. A noble metal is one whose oxide is decomposed at a temperature not higher than a red heat, e. g. platinum, mercury and gold. A base metal is one whose oxide requires tem- peratures higher than a red heat and the use of a reducing agent to decompose them, e. g. lead, copper, and iron. Mention the three only metals which are attracted by the magnet and which can themselves become magnets. Iron, nickel, and cobalt. 2jo CHEMISTR Y AND METALL URGY. Give the chemical equation for the formation of water from its elements. 2H 2+ 2 +Heat=:2H 2 0. What is the difference between deliquescence and efflorescence ? Give examples of each. Some solid substances have the power of absorb- ing moisture from the air which is called deliques- cence', and the property which certain crystallized substances have of loosing water of crystallization when exposed to the air is known as efflorescence. Calcium chloride and potassium hydroxide are exam- ples of the former, and ferrous sulphate and sodium carbonate are examples of the latter. What is aqua regia and its principal property ? Aqua regia is a mixture of water, nitrosyl chlor- ide and chlorine gas, obtained by adding nitric acid to hydrochloric acid. It is a solvent for gold and platinum. It is also used medicinally. What is CaS0 4 and what are its uses in dent= istry ? CaS0 4 containing water of constitution is gypsum. On being roasted it parts with a portion of its water forming Plaster-of-Paris. This latter sub- stance is used for taking impressions or models of the interior of the mouth. What does the term carat signify ? The term carat refers to the proportionate amount of pure gold in a gold alio}', e. g. Pure gold CHEMISTR Y AND METALL URGY. 231 being 24 carat, 18 carat gold being 18 parts gold and 6 parts alloy, What do you know about Hg as a metal ? How are impurities detected and how readily removed ? Mercnry is the only metal liqnid at ordinary temperature, and resembles silver in appearance. Sp. Gr. 13.56. It does not tarnish in air and dissolves all metals except iron to form amalgams. A globule of Hg should be round. If it assumes an elongated shape or leaves a metallic mark as it passes over a smooth surface it is impure. To purify Hg distil it, or cover its surface with nitric acid and after 24 hours, decamp liquid and wash with water. Why cannot amalgam of aluminum and mercury be employed in filling cavities in teeth ? Because the formation of an aluminum amalgam is characterized by an exhibition of the affinity of aluminum for oxygen and its setting is attended by the evolution of great heat, expansion, oxidation of the instruments used, crackling of gas disengage- ment. Why do we find the quality of cohesiveness more marked in Gold than in Silver, Copper and Lead ? Because gold is of a closer texture than other metals. It does not oxidize directly and is probably not volatile. It has the power of welding when cold. How is hydrogen dioxide obtained and what is its formula? Formula, H 2 2 . Hydrogen dioxide is obtained by the decomposi- tion of barium dioxide by sulphuric acid, Ba Q 2 + 2 3 2 CHE MIS TR Y AND MET ALL UR G Y. H 2 S0 4 = Ba S0 4 + H 2 2 . The H 2 2 thus ob- tained is not pure, but contains a considerable quan- tity of water which is necessary to affect the decom- position. From the aqueous solution we can produce a 50% solution by 'evaporation at a temperature not exceeding 140 F. If this is heated in vacuo at an increased temperature a nearly pure hydrogen dioxide is obtained by distillation at a temperature of 185 ° F. What is purple of cassius and how does it interest dentists ? Purple of cassius is a purple precipitate pro- duced by a mixture of stannous and stannic chlor- ides with gold chloride. It is used by manufacturers of porcelain teeth in obtaining the gum color. What are the chemical constituents of tooth enamel ? Salts of lime, the calcium phosphate being in excess while the calcium carbonate and calcium fluor- ide are in smaller quantities. Name some of the more malleable metals ? Gold, Silver, Tin, Copper, Cadmium, Platinum, Lead and Zinc. What is meant by specific gravity and how is it obtained ? Specific gravity, or specific weight, denotes the weight of a substance as compared with the weight of an equal bulk, or equal volume, of another substance, which is taken as a unit or standard. To find the specific gravity of a solid or liquid, divide the weight of the solid or liquid by the weight of an equal vol- CHE MIS TR Y AND ME TALL UR G Y. 233 ume of water at 6o Q F. We may also find the spec- ific gravity of liquids by an instrument known as hydrometer; or, if made for some special purposes, as urinometers, alcoholometers, etc. The specific gravity of gases is determined by weighing the dried gas in a flask ; then exhausting the flask and filling it with dried hydrogen or air, and again weighing. If the temperature and pressure remain the same, divide the weight of the gas by the weight of air or hydrogen. Give the chemical formula for each of the following: Sulphate of Copper, Nitrate of Silver, Iodide of Potas= sium. Sulphate of Copper, CuS0 4 . Nitrate of Silver. AgN0 3 . Iodide of Potassium, KI. Write the equation for the reaction of Sulphuric Acid on common salt. 2 Na CI + H 2 S0 4 = 2HCI + Na 2 S0 4 . Why are the salts of some metals called Sul= phides, Sulphites and Sulphates? Sulphides are binary compounds, one of the ele- ments being sulphur ; sulphates and sulphites are oxy-salts, the sulphates containing a relatively larger quantity of oxygen. What are the essential properties of an Acid ? (a) The hydrogen present is replaceable by metals, the compound formed being a salt. (b) They change the color of many organic sub- stances. Litmus is changed from blue to red. 2 34 . CHEMISTR Y AND METALL URG Y. (c) They have (when soluble in water) an acid or sour taste. (d) It unites with and neutralizes the bases. (e) When concentrated it corrodes tissues. What are alkaloids? Name three. Alkaloids are active principles of organic sub- stances. They all contain nitrogen and are alkaline in reaction. Morphine, Strychnine, Quinine. By what principle do elements combine to form compounds ? In obedience to the laws governing chemical affinity. Electrical force plays an important part in the production of compounds. What is the compound of oxygen and another element called ? An oxide. What influence has temperature on a mixture of oxygen and hydrogen ? It produces an explosion with formation of water. How is muriatic acid prepared? Give the equa= tion. By roasting a mixture of sodium chloride and sulphur. NaCl+H a S0 4 =NaHS0 4 +HCL Give examples of analysis and synthesis. Heating mercuric oxide produces the metal mer- cury and the gas oxygen. (Analysis). Passing an electric spark through a mixture of equal volumes of hydrogen and chlorine produces hydrochloric acid. (Synthesis). CHEMISTRY AND METALLURGY. 23 5 Give the formula of carbolic acid, Mention an antidote. Carbolic acid, C 6 H 6 0. Antidote, a soluble sulphate, as epsom salt. By what force do atoms unite to form compounds ? Give an example. By the force of chemical affinity. Example, H 2 +Cl 2 -|-electricity==2HCl. Mention a solvent for gold and platinum, giving formula. Aqua regia; 3HC1+HN0 3 =2H,0 + NOC1+ Cl 2 . What is a chemical equation ? A chemical equation gives the formulae of sub- stances that undergo chemical action and the for- mulae of substances produced by chemical action. What is the source of tartaric acid ? Give its use in medicine. Fruit substances, particularly grape juice, in which it occurs as a salt called argol. Used in medicine as one of the ingredients of Seidlitz Powder, and its potassium and sodium salt is used as a laxa- tive. How is molecular weight obtained ? By adding the atomic weights of the elements forming a compound or by taking twice the density of a compound. What is meant by chemical reaction ? Chemical reaction represents by formula the re- 236 CHEMISTR Y AND METALL URGY. arrangement of atoms and radicals after they have, through chemical action, been separated from their former union. Name three metals and give the symbols and the atomic weight of each. Iron, Fe, 56. Gold, An, 196.6, Aluminum, Al, 27. What is ozone ? Name some of its properties ? Ozone, 3 , is electrified oxygen and is a blue gas acting strongly as a bleaching and disinfecting agent. Pure gas is irritating when breathed. Name the constituent elements and the properties of the atmosphere. Oxygen, active substance in supporting life. Nitrogen I ^ j-i i- -, > 1 o dilute oxygen to proper limit. Few others. How is aluminum obtained ? Give its symbol and its atomic weight. Aluminum is obtained by electrolysis upon fused bauxite. Symbol, Al. Atomic weight, 27. Give process of refining Gold by chemicals. By fusing silver with gold, rolling it thin, and subjecting it to the action of nitric acid or sulphuric acid. CHEMISTR Y AND METALL URG Y. 237 Name three acids used in medicine. Give form- ula for each. Acetic Acid, HC 2 H 3 2 . Sulphuric Acid, H 2 S0 4 . Hydrochloric Acid, HC1. Describe five metals and give the fusing point of each. Tin (fusing point, 442 ° F.) is a soft, silvery white, malleable metal, and is present in solder. Lead (fusing point, 61 7 F.) is a bluish, soft, malleable, ductile metal ; it is slightly tenacious and resists the action of sulphuric acid. Zinc (fusing point, 779 P.) is a silvery white, highly crystalline, brittle metal ; it is ductile and malleable at certain temperatures. It is used in solder. Gold (fusing point, 201 2 F.) is a yellow, soft, most malleable and ductile metal ; it is insoluble in single acids. Copper (fusing point, 2192 F.) is a flesh color, or reddish, malleable metal ; it is ductile, tenacious, tough and soft. Describe the chemical process by which minerals are converted into animal food. Mineral substances are dissolved in water from which they are absorbed by the rootlets of plants; then, stored in the tissues or fruits of the plant, they con- stitute a food for animals. This, undergoing pro- cesses of digestion and absorption in the animal, is converted into animal tissue. What is the difference between two acids com= posed of the same elements, the name of the one ending 2j8 CHE MIS TR Y AND MET ALL UR G Y. in OUS, and that of the other in IC ? Illustrate, giving name and formula. The one ending in ous contains relatively less oxygen than the one ending in ic. Sulphurous Acid, H 2 SO s ; Sulphuric Acid, H 2 so 4 . Write the equation showing the reaction of sul= phuric acid on common salt. State a general theory to this particular reaction. If two chemical compounds be brought in contact with each other, should one or more elements of one of the compounds have an attraction or affinity for one or more elements of the other compound, these elements will leave their compound, and, uniting, form new bodies. H 2 S0 4 + NaCl = NaHS0 4 + HC1. Distinguish between an element and a compound. Give an example of each. An element is a substance, the molecules com- posing which, contain the same kind of atoms ; for example, copper, gold. A compound is a substance, the molecules composing it are formed of different kinds of atoms, e. g. water, alcohol. Define effervescence, hydrate, and hydrite. Bffervescence is the escape of a gas through a liquid, producing bubbling. A hydrate is a combin- ation of a metal with a member of the water type, as KHO. An hydrite is an oxide of an elementary sub- stance, usually nonmetallic, which will unite chemi- cally with water to form an acid. CHEMISTR Y AND METALL URG Y 2 39 riention six nonmetallic and six metallic elements. Give the symbol of each Non-metallic : Metallic : Chlorine, CI. Iron, Fe. Iodine, I. Copper, Cn. Bromine, Br. Gold, An. Fluorine, F. Silver, Ag. Sulphur, S. Mercury, Hg. Boron, B. Calcium, Ca. Give an example of (a) a physical change, (b) a chemical change, (c) a mixture, (d) a chemical compound. (a) The dissolving of iodine in alcohol. (b) Union of silver with nitric acid to form lunar caustic. (c) Iron filings with sulphur. (d) Apply heat to above, they unite chemically to form a body having different properties than either alone. Classify the following acids, bases, or salts ; (a) lime, (b) vinegar, (c) cream of tartar, (d) baking soda, (e) ammonia. Acids : Bases : Salts : Vinegar Lime Cream of Tartar Ammonia Baking Soda How does N 2 rank as a supporter of combustion and respiration ? It supports combustion but does not support ani- mal respiration. Define negative element, positive element. Men- tion the conditions under which negative and positive ele- ments act on each other. Illustrate this action. 240 CHEMISTR Y AND ME TALL UR G Y. A negative element is one which if freed from a compound by electrolysis would be found at the posi- tive electrode. A negative element is one that com- bines with oxygen to form an acidulous compound. A positive element is one that combines with oxygen to form a basic or neutral oxide. A positive element is a metal. A negative element is a metalloid. How is matter classifed ? Simple and compound. Mineral, animal and vegetable. Organic, inorganic and organized. Atom, molecule and mass. What does HO represent ? One molecule of peroxide of hydrogen. What per cent, of C0 2 exists permanently in the atmosphere ? What per cent, of CO is dangerous to life ? Four parts of CO a exists permanently in ioooo parts by weight of air. More than six parts in 10 ooo parts, if accompanied by respiratory impurities, is dangerous to life. Air containing one-twelfth of its volume of C0 2 produces suffocation. In what condition are elements generally found in nature ? flention two exceptions. In combination with other elements forming compounds. Exceptions diamond and oxygen in the air. CHE MIS TR Y AND ME TALL UR G Y 241 In making dental alloy, state the order of fusing the metals so that volatilization of the base metal may be prevented. Melt the highest fusing metal first. Protect its surface well with borax. Add the other metals in the order of the fusing points, the lowest fusing metal last. For what element is there the most extensive affinity ? Oxygen. Describe the preparation of plaster=of=Paris. Ex= plain the setting of plaster=of=Paris. By roasting gypsum at temperatures between 300 and 400° F., when it looses about ^3 of its water, and then powdered. In the setting, the water added to it unites to plaster-of-Paris to give a substance closely resembling gypsum. What salt of silver is used in dentistry ? Give its formula. Nitrate of silver, AgN0 3 . Mention four compounds giving the symbol and the molecular weight of each. C0 2 — Carbon dioxide — 44. S0 2 — Sulphur dioxide — 64. N 2 — Nitrous oxide — 44. H 2 2 — Hydrogen peroxide — 34. What metal is the best conductor of heat ? Of Electricity ? 2^2 CHEMISTR Y AND METALL URGY. Silver is the best conductor of heat and electri- city. What is a metal ? An element generally solid, at ordinary tempera- tures (mercury is an exception) fusible by heat, insol- uble in water, with a metallic lustre and properties of conducting heat and electricity. Name three light metals, giving the symbol and the atomic weight of each. Metal. Symbol. Atomic Weight. Lithium : Li. 7- Potassium : K. 39- Sodium : Na. 23- Define atom, molecule. An atom is an individual particle of an element. A molecule is the smallest part of any substance that can exist alone and exhibit the properties of that sub- stance. It is a cluster of two or more atoms bound together by chemical affinity. Give the number of elements ? Name three ele= ments stating symbol and atomic weight of each. There are about 76 elements. Element Oxygen : Hydrogen : Nitrogen : What is meant by analysis ? Analysis is the process of determining the comp- position of a body by separating the elements. Symbol Atomic Weight O. 16. H. 1. N. 14. CHEMISTR Y AND METALL URG Y. 243 What is synthesis ? Synthesis is the process of producing bodies by combining elements. Give the atomic weight and the symbol of gold, silver. Metal Symbol Atomic Weight Gold : Au. 197. Silver : Ag. 108. State the theory of valence. Valence expresses the numerical power for union by volume which different elementary substances show. State how to obtain an atomic weight. The atomic weight equals 6.4 divided by the specific heat of the element. Define electrolysis. Describe an experiment illus= trating electrolysis. Electrolysis consists of the separation of the con- stituents of a compound through the action of an electric current. Iodine may be separated from potas- sium by passing an electric current through a solution of potassium iodide. Describe in detail the process of electro=p!ating. A trough made of wood contains a solution of chloride and cyanide of gold. Two wires from a bat- tery pass over the trough. From one, the positive wire, is suspended a gold coin. From the other, the negative wire, is suspended the object to be plated. The current flowing, gold leaves the solution and is 244 CHEMISTR Y AND METALL URGY. deposited upon the object to be plated. The weak- ened solution then dissolves from the gold coin suffi- cient gold to restore its strength. Compare gold, silver, copper and tin as to conduc= tivity of heat? Silver, copper, gold, tin. Give the name and the properties of H 2 S0 4 . De= scribe the manufacture of H.,SO,. H 2 S0 4 is sulphuric acid. It is highly corrosive, strong acid, heavy, oily-like liquid. It is known as a mineral acid, combines with water with great eleva- tion of temperature. Dissolves many metals. Sulphur or a sulphide is burned in air and the resulting S0 2 gas together with HN0 3 gas and steam pass into a leaden-lined chamber. These three vapor substances combine to form H 2 S0 4 , which liquefying falls in a rain to the floor of the chamber ; from this it is removed and concentrated by heat. Give the properties of iodine and state its use in dentistry. Iodine is a solid, purplish-black, shining, scale- like substance, non-metallic, but slightly soluble in water and freely soluble in alcohol, ether, and chloro- form. Its solution in alcohol is known as a tincture and is a counter-irritant ; a stronger tincture contains ether and is known as the dental tincture. It is used to remove green color from teeth. What is meant by spectrum analysis ? Spectrum analysis is a method for recognizing CHEMISTR Y AND ME TALL UR G Y. 245 the presence of different substances owing to charac- teristic optical effects produced when such substances are viewed through a prism. Define cohesion, adhesion, elasticity. Cohesion is that force wdiich binds the mole- cules of like character together. It is interior union. Adhesion binds molecules of unlike character together. It is surface union. Elasticity is that property by virtue of which substances resume their former size and shape when they are relieved from the action of force upon them. Distinguish between oxygen and ozone. Oxygen is a colorless gas, and there is no diffi- culty experienced in inhaling it. Ozone has a blue color and is very irritative when inhaled. Ozone may produce hemoptysis. Ozone is far more active in oxidizing substances than oxygen. A molecule of oxygen contains two atoms, while a molecule of ozone contains three atoms. Distinguish between alkali and alkaloid. Give examples. An alkali is an oxide or hydrate of an alkaline metal. It is a miueral substance turning red litmus blue. It neutralizes acids to form salts and water, forming soaps and fat. An alkaloid is an active principle of an organic substance, and is alkaline in reaction ; it always con- tains nitrogen and, in addition, carbon, hydrogen, and often oxygen. 246 CHEMISTR Y AND MET ALL UR G Y. Alkali, e. g. caustic soda, caustic potash. Alkaloid, e. g. morphine, nicotine. Describe the construction of each of two galvanic cells and mention the chemicals used in each. Grove cell. — Hard rubber cup filled with dilute H 2 S0 4 , containing U shaped strip of zinc. Immersed in this cup is a porous cup filled with strong nitric acid and sheet of platinum. Bunsen cell. — Exactly as above save that carbon is in porous cup in place of platinum. Describe the preparation of hydrogen. Place zinc in sulphuric acid and hydrogen gas will be evolved. Give the manufacture of chloroform. Chloroform is obtained by distilling a mixture of bleaching salt of lime and alcohol. By what processes are constituents of compounds obtained ? Give an example. By electrolysis and by heat. Separation of oxy- gen and hydrogen from water by electrolysis. Separation of oxygen and mercury from mer- curic oxide by heat. Explain the use of atomic weights. Atomic weights are used as combining weights, giving us the proportion by weight of one element required to unite with a definite weight of a second element in forming a compound. How can it be determined that the composition of water is H 2 0. ? CHEMISTRY AND METALLURGY. 2tf By passing an electric current through water obtaining the two gases hydrogen and oxygen. (Anal- ysis). By mixing two volumes of hydrogen and one volume of oxygen and passing an electric spark through it, the result producing water. (Synthesis). Define metallurgy. Metallurgy treats of the economical extraction of metals from their ores and the application of metals to useful purposes. It includes a description of the metal. Explain the use of symbols and formulae. Give and translate five examples of each. A symbol is used to represent one atom of an elementary substance. A formula is a combination of symbols that re- present one molecule of a substance. Examples of symbols. --Oxygen, O; hydrogen, H; sulphur, S; Nitrogen, N; chlorine, CI. Examples of formula.— Water, H 2 ; nitric acid, HN0 3 ; sulphuric acid, H 2 S0 4 ; hydrochloric acid, HC1 ; ozone, 3 . Mention three heavy metals. Give symbol and atomic weight of each. Gold, Au. 196.6; platinum, Pt. 197; mercury, Hg. 200. flention five constituents of the atmosphere. Oxygen, nitrogen, argon, water vapor, carbon dioxide. Give use of sulphuric acid in dentistry. 248 CHEMISTR Y AND METALL URG Y Used as a local application in root canals, clean- ing plates, refining gold, pyorrhoea. Where gold and amalgam are used in approximate cavities, which metal has the greater effect on the sur= rounding dentine ? Gold. State a process by which the constituents of mat= ter are obtained. Illustrate. By electrolysis of water we may obtain its con- stituents in gaseous form. State use of H 2 2 . As a disinfectant, bleaching and oxidizing agent. Distinguish between a simple molecule and a com= pound molecule. A simple molecule is composed of atoms of the same kind. A compound molecule is composed of atoms of different kinds. flention two ways in which elements occur in nature and give examples of three elements occurring in both of these ways. In uncombined state. In compounds or union with other elements. Oxygen mixed with nitrogen equals air. Oxygen combined with metals occurs as oxides. Nitrogen found elementary in the air. Nitrogen found combined in nitrates. Carbon found elementary in diamonds. Carbon found combined in carbonates. CHEMISTR Y AND MET ALL UR G Y 249 Define anhydrous, alkaline, neutral. Anhydrous is a substance deprived of water ; as, anhydrous sulphate of copper. Alkaline refers to the property a substance has which, when in solution, turns red litmus paper blue, unites with and neutralizes acids, forming salts; emul- sifies fats, makes soap, and possesses a harsh acrid taste. Neutral refers to that condition in which a sub- stance showing neither acid nor alkaline properties does not affect litmus in color. Define tenacity. Tenacity refers to the strength or resistance sub- stances show to mechanical force seeking to pull the molecules apart. riention (a)two disinfectants, (b) two antiseptics. Give an example of the use of each. S0 2 , sulphur dioxide, and H 2 2 , hydrogen per- oxide, are two disinfectants. Sulphur burned in a room produces S0 2 , which destroys germs. Hydro- gen peroxide in official solutions is added to collec- tions of pus when, by direct oxidation, it destroys the germs present. Bichloride of mercury and boric acid are two antiseptics. The parts bathed by a solution of bichloride of mercury in a proportion of one part in two thousand parts of water, render the field non-fertile for development of germs. Boric acid in three per cent, solution applied to the eye renders the field non-supportive of germ life. 2 so CHE MIS TR Y AND ME TALL UR G Y. Define chemical affinity. Chemical affinity is a peculiar force which acting at inappreciable distance binds elements and com- pounds together in chemical union forming new bodies. What proportion of the air is nitrogen ? One-fifth. Give formulas of three chemical compounds. Water, H 2 ; nitric acid, HN0 3 ; potassium iodide, KI. How is molecular weight obtained ? Give illus= trations. Molecular weight is obtained by taking the sum of the atomic weights. Molecular weight of H 2 equals 2 + 16 or 18. Molecular weight of H 2 S0 4 equals 2-1-32+64 or 98. flention three acids commonly employed in dent= istry and give the specific use of each. Sulphuric acid, — local application to root canals. Also used for refining gold and cleaning plates. Nitric acid, — used for refining gold, dissolving metals, and as an oxidizing acid. Glacial phosphoric acid, — its solutions are added to zinc oxide in making oxyphosphate of zinc cement. Describe a method of (a) refining gold sweepings and fillings, (b) separating gold from platinum. CHEMISTRY AND METALLURGY. 251 (a) Roast with potassium nitrate in a well boraxed crucible and pour out into moulds. (b) Dissolve the alloy of gold and platinum in aqua regia, dilute well, and add ferrous sulphate sol- ution ; collect the precipitate, wash with water, heat to fusion, and mould in ingot. Give the symbol and the valence of each of the fol= lowing; Hydrogen, oxygen, nitrogen, carbon, gold, iron, mercury, potassium. Symbol Valence Hydrogen, H 1 Oxygen, O 2 Nitrogen, N 5, 3 ° r i Carbon, C 2 or 4 Gold, An 3 or 1 Iron, Fe 2 and 4 Mercury, Hg 2 Potassium, K 1 State the conditions that generate galvanic cur= rents between gold and amalgam fillings and the condi= tions under which such currents may be avoided. In case of galvanic currents which metal, gold or amalgam, most affects the pulp ? If gold and amalgam fillings be in contiguous teeth and there be an acid salivary secretion, gal- vanism may occur. Currents may be avoided by not bringing different metals close together and by neu- tralizing acid saliva. Under the influence of galvanism gold affects the pulp most. What salt of iron is used as an antidote for ar= 2 5 2 CHEMISTR Y AND METALL URG Y senic poisoning ? State how this salt may be rapidly pre- pared. Freshly prepared hydrated sesqui oxide of iron. This may be obtained by adding a teaspoonfnl of ammonia to a cupful of tincture of the chloride of iron and quickly washing the precipitate with water. Give the common names of Ii 2 0, HNO , H 2 C0 3 , and N 2 0. H 2 0, water ; HN0 3 , nitric acid ; H 2 CO„ carbonic acid ; N 2 0, laughing gas. What special properties of metals are most af= fected by alloying. Malleability and ductility are lessened. Tenacity and hardness are increased. Fusibility is lowered. Mention five elements, giving the symbol and the atomic weight of each. Symbol Oxygen, O Sulphur, S Iron, Fe Aluminum, Al Gold, Au Describe the Bunsen burner and give the chemis- try of its flame. The Bunsen burner consists of a tube for the burning of gas, at the bottom of which are apertures for the admission of air. The air so dilutes the gas that all parts of the gas undergo combustion ; carbon dioxide" and water result from the burning. Describe the apparatus for generating electric cur- Atomic we ight 16 32 56 27 196.6 CHEMISTR Y AND MET ALL UR G Y. 2 5 j rents from chemical action. State the chemical action in= volved in the process. A sheet of copper and a sheet of zinc placed in dilute sulphuric acid Mall generate an electric current because the zinc will be acted upon chemically by the acid more than the copper. A solution of sulphate of zinc will form in the acid. Mention four of the principal elements found in the human body. Sodium, oxygen, calcium and iron. Give some of the characteristics of aluminum. State how aluminum is obtained from the ore. Aluminum is a white metal and is malleable, strong and tenacious ; it does not tarnish in the air and has a specific gravity of 2.58. It is obtained from bauxite by passing an electric current through it when fused. Bauxite is a hydrated silicate of alu- minum. Describe the manufacture of N 2 0. N 2 is obtained by heating ammonium nitrate at heat not exceeding 470 F. to 500 F. The vapor then passes through potassium hydrate solution, then through ferrous sulphate solution and then through water. Reaction— NH 4 N0 3 + heat=2H a O+N 2 0. Give an antidote for carbolic acid. A soluble sulphate, as magnesium sulphate. What is understood by H 2 S0 4 ? One molecule of sulphuric acid. 254 CHEMISTR Y AND ME TALL UR G K Give an antidote for corrosive sublimate and sugar of lead. Albumen, as white of egg, is an antidote for cor- rosive sublimate. A soluble sulphate, as epsom salts, is an antidote for sugar of lead. What is fermentation ? Fermentation is the decomposition of non-nitro- genous organic substances produced through the agency of nitrogenous bodies called ferments. Give two methods of refining gold. The roasting process. — Impure gold is placed in a graphite crucible that has been well boraxed, its surface is covered with potassium carbonate, heated to fusion, when potassium nitrate and more borax are added ; after roasting for from one-half hour to an hour, base metals are oxidized and resultant refined gold is poured into a mould. Wet method. — By quartation, add approximately three times as much silver as gold, fuse, cool, roll out, and digest in nitric acid or sulphuric acid, when gold is left undissolved. How do you reduce to higher from lower carat ? To reduce gold from a lower to a higher carat add pure gold or fine alloy. As the alloy in the re- quired carat is to the alloy in the given carat, so is the weight of the alloyed gold, used, to the weight of the reduced alloy, required. The weight of the al- loyed gold, used, subtracted from this, gives the amount of pure gold to be added. CHEMISTR Y AND mAtALL URG K 255 What is the difference between assay and analy= sis ? Ail assay is a process for determining the pro- portion by weight, of one or several metals in a com- pound, as an ore. Ananalys is is used for determining the proportion by weight of all substances in a com- pound non-metallic as well as metallic. Give common name for zinc sulphate, copper sul= phate, aluminum oxide. Zinc sulphate— White vitriol. Copper sulphate— Blue stone. Aluminum oxide— Alumina. How do you find the carat ? As the weight of the alloyed mass is to the weight of gold it contains, so is 24 to the standard sought. ( Gold 6, ~\ What carat would 1 Silver 2, |- be ? ( Copper 1, J 9 : 6 : : 24 : x x=6x24-^9=i6, etc. Would you use silver in making plates ? Why ? No. Because silver is blackened by the sulphur gases forming in the mouth from the decomposition of food particles. State the properties of N 2 which make it of use in medicine. It is used for producing anesthesia of short dura- tion . 256 CHEMISTR Y AND METALL URG K Mention the chemical constituents of saliva. Water, 994.10 Solids : Ptyalin, - 1.41 Fat, ------ 0.07 Epithelium and Proteids (including serum-albumen, globulin, mucin, etc.) 2.13 Salts : Potassium Sulpho-Cyanate, Sodium Phosphate, Calcium Phosphate, Magnesium Phosphate, Sodium Chloride, Potassium Chloride. 1000 What is the difference between a mixture and a chemical compound ? Mixtures are joined together by adhesion and cohesion, and can be separated by such mechanical means as heat and filtration, and may be mixed in any proportion. A chemical compound is one joined by chemical affinity. Give the formula and properties of (a) hydro= chloric acid, (b) sulphuric acid, (c) sulphurous acid, (d) phosphoric acid. Hydrochloric acid (HC1) is a colorless gas, has a sharp penetrating odor, and is very irritating when CHEMISTRY AND METALLURGY. 257 inhaled. It is neither combustible nor a supporter of combustion, and has great affinity for water. Whilst hydrochloric acid is a gas, this name is used also for its solution in water. The hydrochloric acid of the U. S. P. is an acid containing 31.9 per cent, of HC1, and is a colorless, fuming liquid. Sulphuric acid (H 2 S0 4 ). Pure acid has a specific gravity of 1.848 ; it is a colorless liquid, of oily con- sistence and has a great tendency to combine with water, absorbing it readily from atmospheric air. Upon mixing sulphuric acid and water heat is generated. It also has the property of destroying and blackening organic matter, and has poisonous caustic properties. The sulphuric acid of the U. S. P. should contain not less than 92.5 per cent, of H 2 S0 4 . Sulphurous acid (H 2 S0 3 ) is a colorless acid liquid, which has the odor as well as the disinfecting and bleaching properties of the dioxide ; it is completely volatilized by heat. The acid is easily oxidized by the air. Phosphoric acid (H 3 P0 4 ) is a colorless, odorless, strongly acid liquid, which, on heating, loses water, and finally is volatilized at a low red heat. Give two methods of obtaining hydrogen. (1) By the action of zinc on sulphuric acid. (2) By the electrolytic decomposition of water. Give the symbol and the method of preparation of iodine. State use of iodine in dentistry. Iodin (I) is prepared from any iodid by the 2 5 8 CHEMISTR Y AND METALL URGY. action of a mixture of manganese dioxid and sul- phuric acid. 2KI+MnO,+2H 2 S0 4 =K J S0 4 +MnSO + +2H a O+I a . The tincture is a counter-irritant, astringent, and antiseptic, in the latter office particularly useful in the last stages of putrefactive decomposition. In strong tincture, combined with tincture aconite, it is applied to the gums in chronic pericementitis as a counter-irritant. In diluted tincture it is applied as an antiseptic and astringent in cases of congestion of the gums and pyorrhea alveolaris. Give test for arsenic, antimony and gold. Reinsch's test for Arsenic : A thin piece of cop- per, having a bright metallic surface, placed in a strongly acidified solution of arsenic becomes, upon heating the solution, coated with a dark steel-gray deposit of arsenic, which can be vaporized by appli- cation of heat. Test for Antimony : Add hydrogen sulphide to an acidified solution of antimony ; an orange-red pre- cipitate of antimonous or antimonic sulphide is pro- duced. Test for Gold : Add hydrogen sulphide to a sol- ution of gold ; brown auric sulphide is precipitated, which is soluble in yellow ammonium sulphide. How many nitrogen acids are there? State the name and formula of each. Nitric acid, HN0 3 , Nitrous acid, HN0 2 ; Hypo- nitrous acid, HNO or possibly H 2 N 2 2 . CHEMISTR Y AND METALL URG Y 25Q What is meant by potential as applied to electric bodies ? Potential is the difference in electrical conditions. It represents a stored force, and is present before the wires are connected. It is to electricity what temper- ature is to heat. State the salts that enter into the formation of human bone. Calcium phosphate, sodium chloride, magnesium phosphate, calcium fluorid. HISTOLOGY. What is spongioplasm ? Spongioplasm is a part of the protoplasm of a cell. It is a very delicate network which supports the fluid portion of the protoplasm. What is the nucleus of a cell ? The nucleus is usually a round or oval body sit- uated in the interior of the cell body. It consists, like the protoplasm, of two parts ; (i), the chromatin, having, as the name implies, a great affinity for stains ; it is arranged in the form of a delicate reticu- lum. (2), The achromatin, a clear semi-fluid sub- stance, staining feebly, if at all, and occupying the meshes of the chromatin. Within the nucleus may be seen one or more smaller rounded bodies, — the nucleoli. The nucleus is in many instances limited by a distinct nuclear membrane. What is nuclear matrix ? The nuclear matrix is the inter-fibrillar substance of the nucleus. A clear semi-fluid, homogeneous siibstance. Is dentine developed inwardly or outwardly ? Dentine develops from without toward the papilla. In what manner does dentine increase ? By a gradual deposit by the odontoblasts, of HISTOLOGY. 261 layers of a substance which later becomes calcified. What would be the result of exposing dentine to the actions of a strong acid for several days ? The earthy substance would be removed and a substance yielding gelatin would remain. Name the salivary glands, where do they empty ? The parotid has its duct leading to the oral cavity entering opposite the second molar tooth of the upper jaw. The sub-m axillary enters the mouth on the summit of a small papilla at the side of the frenum of the tongue. The sublingual gland has its outlet at several points on either side of the fre- num of the tongue. What is the structure of human enamel ? Enamel is an exceedingly hard substance. It is composed of elements prismatic in shape, usually six sided, placed vertically to the dentine, and are united by a cement substance. It exhibits parallel stripes representing strata of lime salts deposited, called the stripes of Retzius. What are lacunae ? Lacunae are spaces found in compact bone con- taining bone cells and lymph. They are in reality lymph spaces formed by the osteoclasts. Give the varieties of connective tissue. White fibrous. Yellow elastic. Areolar and modifications : Adipose and adenoid. Mucous or embryonic. * 262 HISTOLOGY, Cartilage. Bone. Dentine. Give the analysis of cementum. Cementum has a composition like that of bone. Of organic matter, there is about 33%. The remainder consists of inorganic substance in the form of the phosphates of lime and magnesium, car- bonate of lime, sodium chloride and calcium fluoride. What is an organic tissue ? An organic tissue is one in which the structural elements are chiefly, if not entirely, composed of living organized substances. From what do the lower teeth derive their vas= cular supply ? From the dental and incisor branches of the internal maxillary artery. It divides into a series of branches, one of which enters the apical foramen to supply the pulp. From what do the upper teeth derive their vascu= lar supply ? From the alveolar or posterior dental and the anterior dental branches of the infra-orbital, which are branches of the internal maxillary. Define lymphatics. Are lymphatics found in the teeth ? Lymphatics are vessels with exceedingly delicate walls, the function of which is to take up the excess of nutrient fluids that have been poured from the ca- HISTOLOGY. 263 pillaries for the nourishment of the tissues, and return it to the blood stream. They also carry the nutrient fluids from the digestive canal. No distinct lymphatics have been demonstrated in the teeth. What is hemoglobin ? The coloring matter of the red blood cell, which, when separated from the blood, crystallizes into the form of elongated prisms. It is a proteid substance having a great affinity for oxygen. State the kinds of nerve fibers. Medullated, or white fibers ; non-medullated, gray, or Remak's fibers. State the function of the salivary glands. The salivary glands secrete a fluid containing a principle called pt3^alin which converts starch into sugar, and also aids in moistening the bolus of food, thus aiding digestion. Describe the secondary dentine. Late in life the pulp cavity becomes more or less filled with a dense substance, the structure of which is intermediate between dentine and bone. It is a secondary dentine, also called osteo-dentine. Describe a ganglion. Ganglia are bulbous structures situated on the posterior nerve roots of the spinal cord, on some of the cranial nerves and in the sympathetic system. They consist of a collection of nerve cells, each being enclosed in a capsule which is continuous with the sheath of the fiber communicating with it. The cells 264 HISTOLOGY are enclosed in a reticulum of connective tissue which also contains additional nerve fibers not connected with the cell. From what germ layers is epithelium developed ? Epithelium is developed from the ectoderm, en- toderm and mesoderm. What is histology ? The term histology is derived from the Greek " histos " a web, or tissue ; and " logos " a treatise. It is that part of science which has for its object the study of tissues. What is protoplasm ? Protoplasm is a proteid substance, containing, in addition, some inorganic substances, viz. : phos- phorus, calcium. Structurally it consists of a retic- ulum, the spongioplasm, in the meshes of which is contained a clear semi-fluid substance, the hyalo- plasm. What is a cell ? A cell is a structural element. It consist of a nucleated mass of protoplasm endowed with the properties of life, — growth, metabolism, reproduc- tion, motion and irritability. What is the peridental membrane ? It is that part of the alveolar periosteum which is reduplicated upon the root of the tooth for the pur- pose of binding the tooth in the socket, producing the cementum, and of supporting blood vessels. HISTOLOGY. 265 Give analysis of dentine and enamel. Dentine contains about 28% of animal matter and 72% of earthy matter. Enamel contains but about 4% of animal matter. The earthy matter in both consists of the phosphates of calcium and mag- nesium, carbonate and fluoride of calcium. What is a tooth germ ? The structure consisting of embryonal tissues from which the tooth is developed. How is bone developed ? (1) In cartilage, where the substitution of cal- cified substance is affected by the osteoblasts. (2) In fibrous tissue, by the deposit of calcified substance upon the bundles of fibrous tissue. (3) From the periosteum, by an ingrowth of periosteal buds. This variety also substitutes cartilage, but differs from the enchondronal in that it grows from the surface. What is epithelium ? Epithelium is an elementary tissue found cover- ing surfaces and lining cavities. The cellular ele- ment exceeds the inter-cellular in amount, the latter consisting of but a small quantity of inter-cellular cement substance. What is cartilage ? One of the dense forms of connective tissue, the matrix of which contains the principle known ' as chrondrin. Of what is each of the following composed : (a) the hair, (b) the nails, (c) the enamel of the teeth ? 266 HISTOLOGY. The hair is a modification of the epithelium of the epidermis ; the nails are a very highly developed part of the stratum lucidum of the epidermis. The enamel of the teeth is a product of the epithelium of the oral cavity. Describe the Haversian system. An Haversian system occurs in compact bone and consists of a system of channels through which the nutrient fluids pass. It consists of the following : a centrally placed canal, the Haversian canal, which is surrounded by concentric layers or plates of bone, the lamellae. Between the plates of bone are irreg- ular clefts, the lacunae, which communicate with each other and with the Haversian canal by means of rad- ially placed canals, — the canaliculi. What is periosteum ? Of what tissues is it formed ? A membrane which, as its name indicates, in- vests the bone for the purpose of supporting the blood-vessels, and, also, to take part in the growth of bone. It consists of two layers ; ( i ) an outer, com- posed of white fibrous tissue, containing numerous blood-vessels. (2) The inner, or osteogenetic layer, which is rich in elastic fibers and spindle-shaped cells, — osteogenetic cells. Describe the formation of the teeth. The teeth are composed of three substances, — the enamel, the dentine and the cementum. The enamel covers the exposed part of the tooth, the crown of the tooth. The cementum covers the part of the tooth HISTOLOGY. 26 j within the alveolus of the jaw. The junction of the enamel with the ceinentum is called the neck of the tooth. The bulk of the tooth is made up of the den- tine, which extends from the root to the crown. Each tooth contains a cavity, the pulp cavity, which communicates with the exterior through a small aperture at the apex of the root, the apical foramen. The cavity contains a soft connective tissue, — the pulp, rich in vessels and nerves. The fang, or root of the tooth has a fibrous investment called the peri- dental membrane, or periosteum. What is an odontoblast ? An odontoblast is a modified and specialized con- nective tissue cell, for the production of dentine. Where are nerve cells found ? Describe their structure and functions. Nerve cells exist in the gray matter of the cere- brum, cerebellum, spinal cord and the posterior nerve root ganglia of the sympathetic nervous system, and in the medullary portion of the supra-renal capsules, according to some authorities. A nerve cell consists of a cell body, — a large nucleated mass of protoplasm having prolongations or poles, and usually containing a nucleus. Nerve cells are classified according to the number of processes, as unipolar, bipolar and multi- polar. Each nerve cell is the point at which a nerve fiber originates in one of the protoplasmic processes, known as the axis cylinder process. The other processes when present are branched, therefore, are called dendrites. The function of nerve cells is to generate nervous impulses. 268 HISTOLOGY. Describe the structure of a salivary gland. A salivary gland is a tubuloracemose gland. It is invested with a fibrous tissue capsule which sends trabeculae into the substance of the gland to divide it into lobes ; these in turn are subdivided into lobules. Each lobule consists of a collection of secreting units, the acini, which are composed of glandular epithelium resting upon a basement membrane. The secretion leaves the gland through its ducts, named according to their position in the gland. The interlobular ducts be- tween the lobules, the intralobular ducts within the lobules, and the intermediate ducts leading from the acini to the intralobular ducts. Acini may be of the serous type,the cells of which are granular and stained deeply ; or mucous, the cells being clear and staining faintly. What tooth germ first appears and at what period ? Of the temporary teeth, the germ for the first molar appears in the sixth week of embryonic life. Is dentine vascular ? Explain. Dentine does not contain blood vessels. It prob- ably receives its nourishment indirectly from the ves- sels of the pulp as does the true bone by means of its canaliculi. Where is Nasmyth's membrane found ? Covering the crown of newly erupted teeth. After activity it soon becomes worn away. HISTOLOGY. 2 6g What is connective tissue ? A tissue of mesodermic origin which is composed of a cellular and inter-cellular substance, the latter being the predominant. The cells vary in shape, be- ing round, spindle-shaped, stellate and fusiform, for the most part. The inter-cellular substance consists of fibres and a matrix which vary in their character- istics in various kinds of connective tissue. Where does cementum form the thickest ? At the apex of the fang of the tooth. Mention the structures contained in a cell. A typical cell contains a cell wall or membrane, cell contents or protoplasm, nuclear membrane, nucleus, nucleolus. Some cells contain merely the protoplasm and the nucleus. What are the primary germ layers ? The ectoderm or epi blast, mesoderm or meso- blast, entoderm or hypoblast. Describe (a) mucous tissue, (b) white fibrous tis= sue, (C) elastic tissue. (a) Mucous tissue is a transparent, jelly-like tissue. Microscopically it is composed of stellate cells arranged in a homogeneous semi-fluid matrix. (b) White fibrous tissue consists of delicate white fibers. It may be dense, as in tendons, or loose, as in areolar tissue. The fibers do not branch. On boiling fibrous tissue it yields gelatin. (c) Elastic tissue consists of yellow highly re- flactile fibers which branch freely and have a great 270 HISTOLOGY. tendency to curl at the free ends. The fibers are very elastic, and when boiled yield elastin. Describe two kinds of bone development. In enchondronal bone hyaline cartilage becomes transformed into osseons tissue. First the cartilage cells multiply and become arranged in vertical rows, particularly at the epiphyses, and the substance be- tween the cells becomes the seat of a deposit of lime salts. In order that the marrow cavity and the Haversian canals or spaces be formed, certain cells called osteoclasts absorb some of the osseous- tissue. In long bones ossification also takes place from the periosteum by periosteal buds growing into the car- tilage. Infra-membranous bone develops in fibrous tissue. The bundles of fibres become calcified by the deposit of lime salts upon them by the osteoblasts. This usually takes place in a manner radiating from a centre of ossification. Describe osteoblast, osteoclast. As osteoblast, is a bone making counective tissue cell. An osteoclast is a cell which absorbs the calci- fied substance of bony structures. State the difference between compact bone and spongy bone. Compact bone is densely made up, being com-' posed of layers of calcified matrix, called lamellae. It contains Haversian canals, with concentric lam- ellae between the Haversian systems, — interstitial lamellae; lamellae concentric with the periphery of HISTOLOGY. 271 the bone ; and, if a long bone, perimedullary lamellae. Spongy bone is loosely constructed, being composed of an interlacement of calcified septa forming spaces called Haversian spaces. What tissue binds together the voluntary muscle fibers ? Extensions from the connective tissue covering of the mnscles, called the endo-mysium. What is the sarcolemma ? The delicate sheath investing the muscle fiber of striated voluntary muscle. Define neuro=epithelium and state where it is found ? Neuro-epithelium is of ectodermic origin, and consists of modified epithelial cells situated at the terminal oj nerves of special sense for the purpose of receiving impulses. Describe the axis cylinder, the medullary sub= stance, the neurilemma. These are parts of a so-called medullated nerve fibre. The axis cylinder is the essential part ; it be- gins at the origin of the nerve fiber in the cell and continues to the termination of the fiber. It occupies a central position in the fiber and appears to be made up of delicate fibrillar, the primitive fibrillae. It is said to have a delicate sheath, the axilemma. The medullary substance is the substance which invests the axis cylinder of medullated fibers. It is known as the white substance of Schwann. It is of a fatty nature and is regarded as serving to insulate the axis 272 HISTOLOGY. cylinder. It is not continuous, being interrupted at points called the nodes of Ranvier. The neurilemma is the primitive sheath forming the covering of the nerve fiber. It is a structureless, transparent mem- brane beneath which are situated nuclei, surrounded by a small amount of protoplasm forming the nerve corpuscles. From what layer of the embryo is the vascular system developed ? From the mesoderm. Where does calcification of a tooth begin ? Calcification of the enamel begins at that part nearest the papilla. In the dentine, it begins at the periphery of the papilla. What tissues are derived from the mesoblast ? All forms of connective tissue, muscular tissue, endothelium of the blood and lymph vessels, pericar- dium, endocardium, pleura, peritoneum, spleen, kid- ney and ureter, testicle and ducts, ovary and Fallopian tubes, uterus and vagina. Describe the cellular elements and the fluid por= tion of the blood. The cellular elements of the blood are the erythrocytes, or red blood cells, and the leucocytes, or white blood cells. The fluid portion is the plasma, or liquor sanguinis, in which the cells are suspended. The red blood cells are of a greenish-yellow cast, but when massed together give the red appearance to the blood. In distinction to the white blood cells, they are not nucleated as the latter are. They occur in HISTOLOGY. 273 the proportion of 500 red to 1 white. White blood corpuscles have the power of amoeboid motion. There are several varieties of leucocytes named accor- ding to the character of the nucleus and affinity for stains. The most important are the polynuclear leucocytes occurring in about 70% of all the leuco- cytes. The fluid part of the blood is a somewhat sticky, clammy fluid. It contains the factors of fibrin, namely, fibrinogen and fibrin ferment, which are the agencies active in the clotting of blood. Differentiate veins and arteries. Veins have, on the whole, much thinner walls than arteries in proportion to the calibre of the ves- sels. The endothelial cells of veins are broader and shorter than in arteries. Veins contain less muscle but more connective tissue than arteries. Most veins have valves. Describe the dental ridge. It consists of a linear thickening of the primi- tive oral epithelium from which the enamel germ is later formed. What layers of the embryo contribute to the de= velopment of the teeth ? The ectoderm and the mesoderm. Which of the permanent teeth first calcify? The first molars (sixth month) in the upper jaw. A little later in the lower jaw. What is the origin of the cementum? 2J4 HISTOLOGY. Cementum has its derivation in the alveolar periosteum. What is a phagocyte ? It is a cell possessing the power of amoeboid movement, by means of which it takes in and incor- porates particles with its own substance. It is usually a leucocyte. What is a vein ? A channel which conveys the blood from the capillaries in the tissues to the heart. Mention the two groups or systems into which the veins are divided. The systemic which conveys the blood from the periphery of the body, and the pulmonary veins which convey the blood from the lungs to the heart. What are leucocytes ? The colorless corpuscles of the blood, usually known as white corpuscles. What is adipose tissue ? A form of loose or areolar connective tissue in which the protoplasm of some of the cells has been replaced by fat. What are arteries ? The vessels which convey the blood from the heart to all parts of the body. How many kinds of bone tissue are there ? Bone is usually divided into two varieties ; ( i ) compact, or dense, and (2) cancellated, or spongy. HISTO.LOGY. 275 What is tissue ? Tissue is an arrangement of structural elements and consists of a cellular and an inter-cellular sub- stance. When the structural elements are of the same type, it is known as a simple or elementary tissue ; when of more than one type, it is a complex tissue. What is the blastoderm ? The blastoderm is a sac-like arrangement of em- bryonal cells formed by the cleavage of the ovum. It consists of three layers : ectoderm, mesoderm and entoderm ; from these all of the tissues of the animal body are developed. How do cells receive their nourishment? Cells are nourished by means of the nutrient blood plasma which escapes from the walls of the ultimate capillaries in the tissue. The cells are lit- erally bathed in the blood plasma. Describe metabolism. Metabolism is the process by means of which, as a result of a series of chemical changes, nutrient substances when taken up by the cells, become an in- tegral part of the cell substance. What is embolism ? The obstruction of a blood-vessel by a particle of coagulum which has been carried in the blood stream from one of the larger vessels until it reaches a vessel, the calibre of which is too small to allow it to pass. 2j6 HISTOLOGY. What is embryology ? That part of science which treats of the develop- ment of the embryo is known as embryology. What are phleboliths ? Literally, " vein-stones ". The term is applied to concretions formed in veins. They usually consist of dense fibrous bodies, the result of calcification fol- lowing a venous thrombus. Describe the development of blood vessels and lymphatics. Having a mesodermic origin, the blood and lymph vessels first appear as " cords " of cells which later become hollow to form tubes. The innermost cells become distinctly flattened to form the endothe- lial linings. The first blood vessels have their be- ginning outside the body of the embryo, in the yolk-sac. Describe the muscular tissue. Muscular tissue is of mesodermic origin and consists principally of elongated cells (fibrous cells) which have the inherent power of contracting. The muscle fibers contain nuclei and, sometimes, that which corresponds to a cell wall, the sarcolemma. Voluntary and cardiac muscles are striated, due to the arrangement of alternate light and dark discs. Non-striated muscle is involuntary. Microscopically, they may be differentiated as follows : HISTOLOGY, 27~ 5triated. Non=Striated. Cardiac. Fibers striated trans- No striations. Striated longitudinally ar.l versely. transversely. Has sarcolemma. Hyaline sheath. No sarcolemma. Nucleus beneath sar- Nucleus in cen- Nucleus oval and in cente: . colemma. i e r. T *--u i T-v, A t , , C1 ribers short. Fibers do not branch except in the tongue.' Fibers branch freely. To what class of tissues do the teeth belong ? With the exception of the enamel, which is v product of epithelium, the teeth belong to the con- nective tissue group. From what is the six year molar derived ? The enamel germ of the first permanent molar appears at the extremity of the dental ridge after the manner of a temporary tooth ; it appears about a week before the budding of the germs of the tem- porary teeth. Give the principal tissues of the animal body. Blood and lymph, epithelium, connective, mus- cular and nervous. The blood and lymph are often classified with the connective tissue. What is exostosis? It is a circumscribed overgrowth of the cemen- tum, extending beyond the line of the fang of the tooth and giving an irregular outline to its external surface. State the functions of epithelium. Protective, secretory, absorptive, to permit ex- change of gases, to produce motion (ciliary), for the reduction of friction (endothelium), and for the recep- tion of nervous impulses. 278 HISTOLOGY. What are the soft fibers of Tomes ? Prolongations of the odontoblasts into the den- tinal tubules are known as fibers of Tomes. State the size, shape and structure of a human red blood cell. The red blood corpuscles are disc shaped, bi- concave, and are 1-3200 of an inch in diameter. They are not nucleated ; and, though they probably have a delicate cell wall, none can be demonstrated. The cell contents contains a substance, hemoglobin, which gives the color to the cell. Describe the structure of arteries. The medium sized arteries are composed of three coats or tunics. The tunica intima (inner), consisting of an endothelial lining, resting upon a sub-en dothe- lial layer of loose connective tissue, which is separ- ated from the middle coat by a layer of elastic tissue, lamina elastica interna. The tunica media (middle) is a muscular tunic and consists of a layer of invol- untary (non-striated) muscle fibers circularly ar- ranged. The tunica adventiha (outer) consists of an admixture of white fibrous and yellow elastic connec- tive tissues. This tunic contains small vessels which nourish the artery, called vasa vasorum. To what tissue does dentine belong? To the connective tissue of the dense variety. What is bioplasm ? The living substance of the cell. The term is often used synonomously with protoplasm. HISTOLOGY. 279 flention the varieties of epithelium. Squamous, columnar, ciliated, glandular, transi- tional, pigmented, and neuro-epitheliuin. The first three may occur in a single layer when it is named " simple " ; or, in several layers when it is called Stratified". Describe the more minute structures which evolve the sense of taste. On the dorsum and sides of the tongue, partic- ularly the former, are elevations of the mucous mem- brane in the form of papillae. A few of the papillae (8-12), situated on the posterior part of the dorsum of the tongue, are sur- rounded by a furrow, hence called the circumvallate papillae. They are arranged in the form of the letter "V", the apex being directed posteriorly. These papillae usually bear secondary papillae. Embedded in the stratified squamous epithelium on the surface of the papillae are oval bodies composed of modified epithelial cells arranged "like the staves of a barrel." These are the taste buds which are communicant with the terminals of the gustatory nerve. The fungiform papillae, more numerous than the circumvallate, receive filaments of the nerves of taste; but there are fewer of the "special endings" than in the circumvallate. Secondary papillae do also occur on the fungiform papillae. The largest number of the papillae is of the 280 HISTOLOGY. conical or filiform variety, consisting of a conical elevation of connective tissue covered with epithelium. They carry the terminals of the nerve fibres to the periphery. Describe the cell structure of articular cartilage. The articular surfaces are covered with hyaline cartilage, the distinguishing feature of which is the translucency of its matrix. The matrix, which pre- sents a homogeneous appearance, contains many cartilage cells which occupy and completely fill spaces called lacunae. Somtimes, two or or more cells occur in a single lacuna. The cells are distinctly nucleated ; the youngest are spindle-shaped and occu- py a position next to the perichondrium, while the oldest cells are deeper and are irregularly rounded, having a tendency to become angulated. How does a mucous membrane differ from a serous membrane ? Mucous membranes line all cavities communica- ting directly or indirectly with the atmosphere. They consist of an epithelial covering, the variety of which varies with the location, resting upon a con- nective tissue base, — the tunica propria. Extensions of the epithelium into the connective tissue beneath, arranged in the form of tubes or sacs (usually the latter) which secrete mucous for the purpose of moistening the surface of the membrane, form the mucous glands. • Serous membranes are found lining closed sacs. They consist of a single layer of endothelial cells HISTOLOGY, 281 resting upon a connective tissue membrane. Minute openings, stomata, existing between some of the cells, communicate with lymph capillaries. The fluid found on the surface of serous membranes comes from the lymph channels. Serous sacs may be regarded as large lymph spaces. Describe the pericemental membrane. Give its origin and function. The pericemental membrane is the fibrous tissue investment which covers the root of the tooth. The fibres composing it run, for the most part, trans- versely. Elastic fibres are notably absent. It has its origin in the outer layer of the dental sac. This membrane serves to hold the tooth in the alveolus, and, to furnish the nutrition to the cementum through the blood vessels it carries. Acting as a cushion, it seems to diminish shock during mastication. Differentiate between osteoclasts and cemento= blasts Osteoclasts are connective tissue cells found in bone forming tissue. It is by their agenc} 7 , the absorption of calcified matrix, that the Haversian canals and spaces are formed. Cementoblasts are also connective tissue cells, but their function is that of depositing lime salts in the matrix of the cementum. Describe the process of dental calcification. At about the end of the fourth month, the enamel of the temporary teeth is formed. From the extrem- ity of the enamel cells, next to the papillae, develops 282 HISTOLOGY. a tuft-like projection, which becomes calcified, forming an enamel prism. The process of calcification pro- ceeds therefore from within outward. At about the same period, the deposit of dentine on the sides and apex of the dental papillae begins, and therefore proceeds from without inward. Calcifi- cation of the dentine is not complete, for the areas known as interglobular spaces are not calcified, nor are the processes of the odontoblasts, — the dentinal fibres. Describe the structure, blood supply and nerves of the pulp. The pulp consists of embr3 T onic connective tissue which is composed of stellate cells arranged in a semi- fluid, transparent matrix. Next to the wall of the pulp canal are columnar shaped cells, the odontoblasts, processes of which enter the dentine as the dentinal fibrils, The pulp is well supplied with blood-vessels and nerves which enter at the apical foramen. After entering the pulp canal they break up to form plex- uses which terminate in the la}'er of odontoblasts. The function of the pulp is that of furnishing nutrition to the dentine and enamel. Due to the rich nerve suppl}^, the pulp is very sensitive. From what is the mesoblast derived ? The mesoblast has its origin partly in the epi- blast and partly in the hypoblast, though chiefly the latter. What two tissues are formed by the dental pa- pilla ? HISTOLOGY. 283 The dentine which is deposited at the periphery of the papilla ; and the pulp, which is that portion of the papilla remaining after the dentine has been formed. Describe separately the calcified products of the connective tissue. Bone may be considered to be of two kinds : compact, or dense, and cancellated, or spongy. Compact bone consists of a dense matrix con- taining lime salts, which matrix contains numerous channels for the passage of nutrient vessels and fluids, also clefts or spaces, containing bone cells. The largest channels (1-500 inch in diameter), called "Haversian Canals", run parallel with the long axis of the bone and form anastomoses with one another. The canals are surrounded with concentric layers of osseous matrix : Haversian lamellae, between which are small spaces, the lacunae, which in recent bone contain bone cells. Radiating from the Haversian canals to the lacunae, are minute channels which con- vey lymph. They are the canaliculi. The above named structures form what is termed an u Haversian System." Between the systems, which are circular, interstitial lamellae occur, thus filling the space that otherwise would exist. Lamellae also occur concentrically with the per- iphery of the shaft of the bone, the circumjerential lamellae, and with the medullary canal, the perime- duttary lamellae. Spongy bone does not contain Haversian Sys- tems, and, therefore, no Haversian Canals. There 284 HISTOLOGY. are, however, as the name implies, numerous spaces in the matrix ; they are known as " Haversian spaces. " Dentine consists of a calcified matrix in which, extending through the entire thickness of the matrix, are seen the dentinal tubules which terminate in irregular clefts at the junction of the dentine with the enamel and cementum. These clefts are known as the interglobular spaces. The part of the matrix immediately surrounding the tubules forms the den- tinal sheaths. The tubules contain processes of cells at the periphery of the dentine, — the dentinal fibres. Cementum resembles very closely the structure of bone. Near the apex of the root, where the cementum is thickest, Haversian canals may some- times exist, though usually the}' are not present. What tissue is the origin of the enamel ? What are ameloblasts ? Enamel originates in the oral epithelium. Ameloblasts are the enamel producing cells. They are distinctly columnar in shape and occup} T a position in the enamel organ nearest the dentine. What cells form Dentine ? The odontoblasts. Describe the development of the dental papilla ? The dental papilla is of connective tissue origin. Its position is first evidenced by a proliferation and condensation of the mesodermic elements. This col- lection of cells soon assumes the shape of a cone, its apex pointing towards, and later invaginated by the HISTOLOGY. 28 5 enamel organ. The apex and sides of the conical mass become surrounded by columnar cells, -the odon- toblasts, which are the producing agents of the dentine. By what cells, and under what condition does re= sorption occur ? Cells which are endowed with the function of breaking down osseous tissue, namely the osteoclasts, are active in the process of resorption. Resorption takes place previous to the eruption of the perma- nent teeth and is stimulated by the increased blood supply stimulated by the pressure of the unerupted permanent teeth. Describe rieckel's cartilage. Meckel's cartilage is a rod of cartilage which appears in the mandibular arch, and partly enters into the formation of the inferior maxilla, namely, the ex- tremity at the symphysis and the proximal extremity, which persists with a covering of fibrous tissue to form the internal lateral ligament of the jaw. The greater part of Meckel's cartilage disappears at about the sixth month of foetal life. Name the specialized cell for each particular struc= ture of the teeth. The specialized cell of the enamel is the amelo- blast. That for the dentine is the odontoblast. For the cementum, the cementoblast. What are interglobular spaces ? At the junction of the dentine with the enamel and cementum are areas which are imperfectly calci- 286 HISTOLOGY. fled ; they are soinewhat globular in shape, hence, called interglobular spaces. Describe the dental follicle. The dental follicle is the result of the condensa- tion of the mesodermic cells surrounding the papilla, which later extends upward so as to surround the en- tire rudimentary tooth. Why should there be a difference between the structure of dentine and cementum ? Dentine is a product of embryonic connective tissue through the specialized cell, the odontoblast ; while the cementum is produced by the connective tissue cells of the alveolar periosteum, the cemento- blasts ; therefore, the structure of the cementum re- sembles that of bone. Describe the enamel organ and the cells that form enamel. The enamel organ has its origin in a down- growth of the oral ectodermic tissue. When full} 7 developed it consists of a sac, the lower margin of which is indented b}^ reason of its contact with the underlying papilla ; structurally, it consists of three layers of cells. An upper, continuous with the super- ficial cells of the ectoderm, a middle layer of stellate cells, and an inferior layer of distinctly columnar shaped cells. The last named cells are the cells which produce enamel. The enamel cells, when ac- tive in the production of enamel, exhibit, at their lower ext remit}' (toward the papilla), a tuft of short HISTOLOGY. 287 processes. It is along these processes that the de- posit of the enamel takes place. What is the primitive dental groove ? What organ of the teeth is developed from it ? A longitudinal furrow, seen on the surface of the ectodermic tissue, which marks the point of attach- ment of the dental ridge, l}^ing immediately be- neath. Describe the dental fibrillae; with what are they connected, and where do they terminate ? The dental fibrillae occupy the dental tubules and extend throughout their length. The fibrils are protoplasmic extensions of the odontoblasts termin- ating at the periphery of the dentine. Describe the stratum granulosum. At the periphery of the dentine, the substance is not completely calcified. As a result there are small irregular clefts, the interglobular spaces. This layer of the dentine is known as the granular layer. What is Neuman's Sheath ? The part of the dentinal matrix immediately surrounding the dentinal tubules constitute the so- called dentinal sheaths, or sheaths of Neuman. Describe the process of absorption. Absorption depends upon a force known as en- dosmosis, which is the change that occurs between fluids capable of mixing with each other through an animal membrane ; by this process the nutrient fluids get from the alimentary canal to the lymph vessels. 288 HISTOLOGY. What is calcification ? Calcification is the process by means of which tissue may become infiltrated with lime salts. It is a product of the cellular element of the tissue that is deposited in the intercellular substance of which it becomes a part. Calcification usually is effected in layers, and, in the instance of bone and cementum, the well defined lamellae are formed. flention the methods of distribution of cells in the various tissues. On surfaces, (epithelium and endothelium). Suspended in fluid, (blood and lymph). Interstitially, in a matrix (connective tissues). What is perichondrium ? A fibrous investment covering cartilage. It con- sists of an outer fibrous, the vascular layer ; an inner chondrogenetic layer, composed of spindle-shaped, cartilage-forming cells, Name the varieties of cartilage. White fibro-cartilage, yellow elastic cartilage, hyaline cartilage. Which variety of cartilage does not have a perichondrum ? White fibro-cartilage. How may all tissues be classified ? According to (i) their ancestry, (2) function, (3) morphological character. Explain the difference between epithelium and endothelium. HISTOLOGY. 289 Epithelium and endothelium occur on surfaces, but the location, the function and the arrangement varies. Epithelium. Endothelium. Ancestry Function M cC'tr l fs^-oui Ectoderm Entoderm Mesoderm (rarely) C Protective Secretory J Absorptive j Permit exchange of gases Motion L Nervous f Simple and Stratified. Mesoderm Reduction of friction Always in a single layer .' Columnar and (^ Polyhedral shaped cells Always squamous. What is meant by the ancestry of a tissue ? Its origin in the blastoderm. What is the function of connective tissue ? Connective tissue enters into the formation of the structure to make a supporting framework ; espe- cially where great strength is required. Blood ves- sels, nerves and lymphatics are always carried in connective tissue. What is the structure of capillaries ? Capillaries are the ultimate radicles of the vas- cular (arterial) system, and consist of a continuation of the lining of those vessels ; being made of a single layer of endothelial cells, united by a small amount of intercellular cement substance. ANATOMY. flention the branches of the facial artery on the face. Muscular, inferior labial, , inferior coronary, superior coronary, lateral nasal and angular. Describe the cavernous sinus. It is lodged in the cavernous groove, which is situated lateral to the sella turcica of the sphenoid bone. It extends from the sphenoidal fissure to the apex of the petrous portion of the temporal bone. Anteriorily it receives the ophthalmic vein, and behind it opens into the petrosal sinus through which the cavernous sinus communicates with the lateral sinus. Describe the Pons Varolii. It is the bridge of union of the various segments of the encephalon, connecting the cerebrum above, the medulla oblongata below, and the cerebellum behind. It is situated above the medulla oblongata, below the crura cerebri, and between the hemispheres of the cerebellum. It is about an inch in length and also in thickness, and about an inch and a half in width. Describe the superior maxillary nerve (second di= vision of the fifth nerve). It is a sensory nerve given off from the gasser- ANATOMY, 2gi ian ganglion. It leaves the cranial cavity through, the foramen rotundum, passes through the spheno- maxillary fossa, then through the spheno-m axillary fissure, enters the infra-orbital canal, and makes its exit on the face through the infra-orbital foramen. The branches of the nerve may be divided in four parts : — In the cranium, the meningeal ; {orbital, or temporo-malar, spheuo palatine, posterior superior dental. Infraorbital canal i mi f dd ! e su P eri ° r dental, ( anterior superior dental. tpalpabral, nasal, labial. Where is the foramen caecum? What does the foramen transmit ? It is situated at the junction of the crista galli of the ethmoid, and frontal crest of frontal bones. It is, as a rule, a blind foramen, but when open, transmits a vein from the nose to empty into the superior longi- tudinal sinus. flention the muscles attached to the temporal bone. Fifteen, viz.: — temporal, masseter, occipito-fron- talis, sterno-mastoid, splenius capitis, trachelo-mastoid, digastricus, retrahens aurem, stylo-pharyngeus, stylo- hyoideus, stylo-glossus, levator-palati, tensor tympani, tensor palati, and stapedius. Describe the thyroid gland. The thyroid gland is a ductless gland, i. e. one that does not possess an excretory duct. It is situated at the anterior aspect of the neck in front of the 292 ANATOMY. trachea, and consists of two lateral lobes connected across trie middle line by a narrow transverse portion, the isthmus. It weighs about one ounce. The lobes are conical in shape, the apex of each being directed upward and outward and the base downward. Give the origin, insertion, nerve supply, and action of the pterygoid muscles. The external pterygoid muscle arises by two heads. The upper head arises from the inferior sur- face of the great wing of the sphenoid and the ptery- goid ridge, the lower from the outer surface of the external pterygoid plate. Its fibers pass horizontally backward and outward to be inserted in the depression in front of the neck of the condyle of the lower jaw, and into the articular fibro cartilage. Internal pterygoid muscle arises from the ptery- goid fossa and is inserted on the inner side of the ramus and angle of the lower jaw. The inferior maxillary nerve supplies these mus- cles. The external assists in drawing the lower jaw forward upon the upper. The internal raises the lower jaw against the upper w T ith great force. Mention the arteries from which the superior max= illary bone derives its blood supply. Alveolar, anterior and middle dental, spheno- palatine and posterior palatine. Describe the salivary glands. Where do these glands empty ? Three pairs in number ; two parotid, two sub- maxillary, two sub-lingual. They are compound ANATOMY. 293 racemose glands, made up of a number of cells, con- nected by a number of tubuli, which empty into a central tube leading to their respective ducts (com- parable, in shape, to a bunch of grapes). The parotid gland is situated in front of the ear and rests upon the tympanic plate of the glenoid fossa of the tem- poral bone, internally, and extends as far down as the angle of the jaw ; anteriorly, overlaps a portion of the masseter muscle. The external carotid artery passes into the gland and gives off the posterior auri- cular, temporal and internal maxillary branches. It is also traversed by the facial nerve which emerges at its anterior border. Its duct (Steno's) is about two inch- es long and empties into the vestibule of the mouth on the inside of the cheek, opposite the second upper mol- ar tooth. This gland weighs from one-half to one ounce. The sub-maxillary gland is situated in the sub- maxillary fossa on the posterior part of the body of the inferior maxillary bone. It lies on the mylo- hyoid and hyo-glossus muscles, and is in relation, externally, with the skin and platysma. The facial artery lies in a groove embedded in its posterior and upper border. Its duct (Wharton's), which is about two inches in length, empties into the floor of the mouth, on the summit of a small papilla situated on the side of the frenum linguae. This gland weighs about two drachms. The sub-lingual gland is the smallest of the salivary glands and is situated in the sub-lingual fossa on the internal surface of the body of the in- ferior maxillary bone, close to the symphysis. It is 294 ANATOMY. in relation above with the muscle of the floor of the mouth (mylo-hyoid). The large duct is known as the duct of Bartholin, and empties into the mouth in common with Wharton's duct. The smaller ducts, ducts of Rivini, 15-20 in number, open into the floor of the mouth. Mention the bones and ligaments of the temporo= maxillary articulation. The condyle of the inferior maxillary articulates with the glenoid fossa of the temporal. The liga- ments are four in number, viz : capsular, internal and external lateral, stylo-maxillary. Describe the hyoid bone. This bone is situated in the supra-thyroid region of the neck, at the root of the tongue, serving for the attachment of the muscles of that body. It is shaped like a horse-shoe, and presents five parts for examina- tion viz. — body, two greater, and two lesser cornua It is suspended by the stylo-hyoid ligament, which is at- tached above to the tip of the styloid process of the temporal bone. Mention the muscles of the pharynx. Inferior, middle and superior constrictors, stylo- pharyngeus, palato-pharyngeus and salpingo-pharyn- geus muscles. Describe and give the articulations of the sphe= noid. The sphenoid is an irregularly shaped bone, situated at the base of the skull. It consists of a body, one pair of greater wings, one pair of lesser ANATOMY. 295 wings, and two pterygoid processes. The body presents on its upper surface from be- hind forward, (a) the dorsum ephippii, surmount. l! by the posterior clinoid processes. (b) The cella turcica or pituitary fossa for the lodgment of the pituitary body ; the fossa limite 1 anteriorly by the middle clinoid processes. (c) An olivary eminence. (d) The optic groove for the optic commissur . (e) The ethmoidal spine for articulation with the ethmoid. Laterally, may be seen the cavernous grooves, for the cavernous sinuses. Anteriorly, the body presents the sphenoidal crest for articulation with the perpendicular plate of the ethmoid ; the openings of the sphenoidal sinuses, and the sphenoidal turbinated bones. Inferiorly, on the body, is seen the rostrum, or beak, which articulates with the vomer. Posteriorly, the body is rough, articulating with the basilar portion of the occipital bone. The lesser wings project from the fore-part of the lateral aspect of the body. The anterior border of each is serrated to articulate with the frontal. At the junction of each wing with the body, is seen the optic foramen transmitting the optic nerve and oph- thalmic artery. The upper surface is smooth for the support of the cerebrum. The inferior surface forms the upper boundary of the sphenoidal fissure. The greater wing in each instance projects from the body of the bone, attached by means of the lin- gula. The upper surface is concaved, receiving the 2 9 6 ANATOMY, temporo-sphenoidal lobe of the cerebrum. From before backward are seen, the foramen rotundum for the second division of the fifth nerve, the foramen ovale for the third division of the fifth nerve, the for- amen spinosum for the middle meningeal branch of the internal maxillary artery. The anterior border of the greater wing, together with the body and lesser wing, form the anterior lacerated foramen or sphenoidal fissure. The pterygoid processes extend downward and backward. Each process possesses an external pter- ygoid plate. At the junction of the internal ptery- goid plate with the body and greater wing, a horizon- tal canal, called the Vidian, extends from behind forward. A subdivided recess is seen between the two pterygoid plates, the upper and smaller division called the scaphoid fossa, the lower and larger being called the pterygoid fossa. Projecting downward from the internal plate is the hamular process. The sphenoid articulates with the other seven bones of the cranium ; also, with the malar, vomer and palate bones. Describe the ethmoid bone. The ethmoid bone is a light spongy bone con- sisting of a body and two lateral masses. The body presents a horizontal plate, perforated for the trans- mission of the olfactory nerve filaments, hence called cribriform. Projecting upward from the anterior median portion of the horizontal plate is the crista galli, serving for the attachment of the falx cerebri. / ANATOMY. 297 The body of the bone also has in relation with it the perpendicular plate, which forms part of the nasal septum. The lateral mass, or labyrinth, of each side, consists of two curling pieces of bone denominated respectively the superior and inferior turbinals, lim- ited externally by a smooth plate of bone called the os planum, which assists in the formation of the inner wall of the orbit. Descending from the lateral mass is the unciform process articulating with the inferior turbinated bones, and assisting in forming part of the inner wall of the antrum of Highmore. Give origin insertion and action of the buccinator muscle. Origin, — From the alveolar processes of the super- ior and inferior maxillary bones, and behind, from the pterygo-maxillary ligament. It is a bipeniform mus- cle, its superior fibres blending with the fibres of the orbicularis oris in the lower lip, its inferior fibres with the fibres of the orbicularis oris muscle of the upper lip. Its action is to assist in keeping the food between the teeth in mastication ; and is used in such acts as whistling, blowing a trumpet or horn. What nerve supplies the muscles of expression ? The facial or seventh nerve. What nerve supplies the muscles of mastication ? Branches of the inferior maxillary division of the fifth cranial nerve. Mention the muscles attached to the occipital bone? 2 9 8 ANATOMY. Occipito-frontalis, trapezius, sterno-cleido-mas- toid, complexus, splenius capitis, obliquus capitis su- perior, rectus capitis posticus major aud minor, rectus capitis lateralis, rectus capitis anticus major and minor, and superior constrictor of the pharynx. Give the articulations of the great wing of the sphenoid. Superiorly, with the frontal, tip of the parietal, the outer and posterior border with the squamous and petrous portions of the temporal, and the outer border of the orbital surface with the malar. What blood vessels supply the antrum and teeth of the superior maxillary ? The molar teeth are supplied by alveolar branches of the internal maxillary artery. The an- terior teeth are supplied by the anterior and middle dental branches of the infraorbital, (a branch of the internal maxillary) artery ; the antrum is supplied by a branch of the same artery. Give the origin and distribution of the facial artery. Origin. — Branch of the external carotid, arising just above the lingual ; gives off branches in the neck to supply the palate, tonsils, sub-maxillary gland, structures around the chin, the internal pterygoid, and stylo-hyoid muscles. On the face it supplies the masseter and buccinator muscles, lower and upper lips, mucous membrane of both lips, side of the nose, the inner angle of the eye, and root of the nose. ANATOMY. 2 99 Give origin and course of three principal divisions of the fifth pair of nerves. Origin. — From the Gasserian ganglion, sitnated at the apex of the petrons portion of the temporal bone ; its three divisions are : first, ophthalmic which traverses the craninm through the sphenoidal fissnre and goes to the region of the eye ; second, superior maxillary which leaves the cranium through the foramen rotundum, passes through the spheno-max- illary fossa and supplies the superior maxillary bone and surrounding structures ; third, inferior maxillary which leaves the cranium through the foramen ovale, passes downward, and, entering the dental canal, sup- plies the inferior maxillary bone and surrounding structures. Name the three classes of articulations. Synarthrosis, amphiarthrosis and diarthrosis. What nerves pass through the spenoidal fissure ? The third, fourth, three branches of the ophthal- mic division of the fifth, and the sixth cranial nerves. Mention the muscles attached to the superior max= illary bone. Orbicularis palpebrarum, inferior oblique, leva- tor labii superioris alaeque nasi, levator labii superi- ors, levator anguli oris, compressor naris, depressor alae nasi, dilator naris posterior, masseter, buccin- ator, internal pterygoid, and orbicularis oris. JOO ANATOMY. Give the articulation of the lachrymal bone. Give the name of the muscle attached to this bone. It articulates with the frontal, superior max- illary, ethmoid, and inferior turbinated bones. The tensor tarsi muscle is attached to the bone. Describe the external jugular vein. It receives the greater part of blood from the ex- terior of the cranium and deeper part of the face, being formed by the posterior division of the tem- poro-m axillary and posterior auricular veins. It be- gins in the parotid gland on a level with the angle of the lower jaw, extends down the neck on, a line drawn from the angle of the lower jaw to the middle of the clavicle, lies in the platysma, and empties into the sub-clavian vein. Describe the common carotid artery. The common carotid artery in the neck, extends from the sterno-clavicular joint upward and back- ward in the carotid sheath, to the level of the upper border of the thyroid cartilage, where it bifurcates into its internal and external branches. In company with it, may be found the internal jugular vein and the pneumogastric nerve. The right common carotid is a derivative of the innominate, whilst the left is a branch of the arch of the aorta. The right begins behind the sterno-clavicular articulation ; the left lies deeply placed, overlapped by the left lung and pleura. Higher up, it lies beneath the sterno-hyoid and sterno- thyroid muscles. The artery on the right is 9. 5 cm. long; on the left, 12 cm. ANATOMY. joi Mention the branches of the hypoglossal nerve. Coranmmcating branches to pneumogastric, sympathetic, one to two cervical nerves, lingual. meningeal, Distributing j descendens hypo-glossus, thyro-hyoid, muscular. branches are Define osteology. Osteology is the science which treats of the structure, development and function of bones. It is that part of anatomy which treats of bones. What bones enter into the formation of the orbi- tal cavities ? The bones entering into the formation of the orbital cavity are the frontal, sphenoid, lachrymal, ethmoid, superior maxilla, malar, and palate bones. Describe the frontal bone and give its articula- tion. The frontal bone is situated at the fore part of the cranium and may be said to possess two portions : viz., a vertical and a horizontal plate. Internally on the vertical plate, may be seen the following : — a groove in the median line for the lodgment of the su- perior longitudinal sinus, the margin of the groove serving for the attachment of the falx cerebri. The foramen caecum, for the passage of a small vein to the sinus. Elevations and depressions accommoda- J02 ANATOMY. ting cerebral convolutions. Externally, — the frontal eminences located on either side of the midline ; the remains of the metopic suture ; two converging super- ciliary ridges ; the convergence marking the nasal eminence, behind which are located the frontal sinuses ; the supra-orbital ridges, terminating inter- nally in the internal angular, and externally in the external angular processes. Between the internal angular processes is noted the nasal notch, from the middle of which projects the nasal spine. The hori- zontal plate consists practically of the two orbital plates, separated by an interval known as the ethmoi- dal notch, which shows on its margins the anterior and posterior ethmoidal foramina. The notch re- ceives the cribriform plate of the ethmoid bone. The upper surfaces of the orbital plates show ridges and depressions to accommodate the convolutions of the cerebrum. The inferior surface of each plate is smooth, serving as the roof of the orbital cavity, marked to the inner side by a small depression, called the trochlear fossa, for the pulley of the superior oblique muscle ; and just within the exter- nal angular process is seen the lachrymal fossa, for the lodgment of the lachrymal gland. The frontal bone articulates with the parietal, sphenoid, ethmoid, lachrymal, malar, superior maxillary, and nasal bones. The frontal also articulates with epipteric bones when they are present. Describe the temporal bone. The temporal bone is located at the lateral and in part the basal area of the skull and consists of ANATOMY. 303 three portions, viz., squamous, mastoid and petrous. The squamous portion of the bone is marked inter- nally by grooves for the meningeal arteries and by depressions for brain convolutions. Externally, this scale-like portion of the bone shows a zygomatic pro- cess going forward to articulate with the malar bone. The process arises by three roots ; the posterior, con- tinuous with the temporal ridge ; the middle, extend- ing at the post-glen oid tubercle ; and the anterior, dipping at right angles to join the eminentia articu- laris. Inferiorly, the squamous portion of the temporal bone exhibits a fossa, called the glenoid fossa, which articulates with the condyle of the inferior maxillary bone. In front of this fossa is seen the eminentia articularis, a rounded bony mass. Dividing the fossa transversely is the Glasserian fissure, which trans- mits the laxator tympani muscle, the tympanic branch of the internal maxillary artery, and lodges the processus gracilis of the malleus. A narrow sub- division of this fissure is called the canal of Huguier. The mastoid portion of the bone projects, nipple-like, downward. Internally, a well-marked groove, called the fossa sigmoidea, is seen, which lodges the termi- nal portion of the lateral sinus. Externally, are seen the mastoid tip, for the insertion of the sterno-mastoid, splenitis and trachelo-mastoid muscles ; digastric fossa, for the attachment of the digastric muscle ; the occi- pital groove, for the occipital artery. On section the bone shows a series of cells opening into the tympan- 3<>4 ANATOMY. urn, The petrous portion of trie bone exhibits a base, marked by the meatus auditorius externus; an apex which assists in the formation of the foramen lacerum medius; an anterior surface, showing from within outward, the opening of the carotid canal ; a depres- sion lodging the Gasserian Ganglion ; two small openings, the larger called the Hiatus Fallopii, the smaller unnamed, transmitting respectively the greater and lesser petrosal nerves ; an eminence marking the superior semi-circular canal, and a translucent plate of bone, the tegnien tympani, overlying the tympanum. The posterior surface is marked by the meatus auditor- ious internus, transmitting the 7th and 8th nerves, together with a small auditory artery. To the outer side and below the meatus auditorus internus a small slit is seen, the aqueductus vestibuli, which transmits in early life the ductus endo-lymphaticus. The in- ferior surface of the bone is marked from within out- ward, by the following : a rough surface, for the attachment of the tensor tympani and levator palati muscles ; a large opening, the carotid foramen, the beginning of a canal of the same name, transmitting the internal carotid artery. Now, a triangular depres- sion is seen, at the bottom of which is the aqueductus cochleae, transmitting a loop of vessels to the cochlea. Next, an irregular fossa, called the jugular fossa, on the outer wall of which is seen the auricular canal, transmitting Arnold's nerve (auricular branch of the 10th). On the ridge between the carotid opening and jugular fossa is seen the tympanic canal for the trans- mission of Jacobson's nerve (tympanic branch of 9th). ANATOMY. 305 To the outer side of the jugular fossa is located the styloid process, for the attachment of the stylo-hyoid, stylo-glossus and stylo-pharyngeus muscles, and the stylo-hyoid and stylo-maxillary ligaments. The open- ing alongside of the process is called the stylo-mastoid foramen, transmitting the facial nerve and the stylo- mastoid artery. The petrous portion of the bone con- tains the tympanum and the aqueductus Fallopii, (live the articulations of the temporal bone. The temporal bone articulates with the occipital, parietal, sphenoid, inferior maxillary and malar bones. From how many centres is the temporal bone de= veloped ? The temporal bone is developed from ten centers. One for the squamous portion and zygoma, one for the tympanic plate, six for the petrous and mastoid segments, and two for the styloid process. Describe the ophthalmic artery. It is a branch of the internal carotid, just as that vessel is emerging from the cavernous sinus on the inner side of the anterior clinoid process, and enters the orbit through the optic foramen below and to the outer side of the optic nerve ; crossing the nerve, it terminates at the internal angular process of the frontal bone, where it divides into the frontal and nasal branches. Describe the pulmonary veins. The pulmonary veins are those vessels which re- turn the arterial blood from the lungs to the left auri_ jo6 ANATOMY. cle of the heart. They are four in number, two from each lung. The pulmonary veins differ from the other veins in several respects ; first, they carry arte- rial blood instead of venous blood ; second, they have no valves ; third, they are slightly larger than the arteries they accompany. They commence in a capil- lary network upon the wall of the air cells, where they are continuous with the capillary ramification of the pulmonary artery, and together form branches which converge to form a single vessel from each lobe, with the exception that the branch from the middle lobe of the right lung empties in the upper of the two right pulmonary veins. Describe the Otic Ganglion. It is a small oval flattened ganglion of a reddish- gray color, situated immediately below the foramen ov- ale, on the inner surface of the inferior maxillary nerve. It receives motor and sensory roots from the inferior maxillary division of the fifth nerve. The small su- perficial petrosal nerve also enters the ganglion as a motor root. It receives its sympathetic root from the plexus surrounding the middle meningeal artery. Give a brief description of the facial nerve. This nerve is the motor nerve to the muscles of expression in the face. Its superficial origin is from the pons at its lower border to the inner side of the eighth nerve. It arises deeply from a nucleus beneath the floor of the fourth ventricle in its upper half. It leaves the cranial cavity through the internal auditory meatus, then ANATOMY. joy passes above the crista falciformis through an opening in the lamina cribrosa, called aqueductus Fallopii, then passes through a canal in the petrous portion of the temporal bone and gives off in this canal a great and small petrosal ; leaving the temporal bone through the stylo-mastoid foramen, it passes through the parotid gland, downward around the angle of the jaw and up across the masseter muscle and breaks up into filaments to supply the muscle. Describe the hypoglossal nerve. It is the motor nerve to the tongue. Its superfi- cial origin is from the side of the medulla oblongata in the groove between the pyramidal and olivary bodies. Its deep origin is from the grayimatter on the floor of the fourth ventricle. It passes out of the cranium through the anterior condyloid foramen to the base of the tongue, and along the tongue to the tip which it supplies. It gives off communicating branches to, Pneumogastric. — First and second cervical nerves. Sympathetic. — Lingual. The branches of distribution are : Meningeal. — Thyro-hyoid. Descendens Hypoglossis. — Muscular. Describe the outer surface of the occipital bone. It is convex ; and, midway between the superior angle and posterior border of the foramen magnum, is the external occipital protuberance. Extending towards the lateral angular process from the external jo8 ANATOMY. occipital protuberance are the superior curved lines of the occipital bone. Passing from this protuber- ance to the foramen magnum is the external occipital crest. Midway between the foramen magnum and the protuberance, extending parallel with the superior curved lines, are the inferior curved lines. The por- tion of bone above the superior curved lines is smooth; over it glides the occipital frontalis muscle. The bone between the lines and the foramen magnum is rough for the attachment of muscles. Describe the inner surface of the frontal bone. It is concave, smooth, and contains eminences and depressions for the reception of convolutions of the brain. In the median line is the groove for the lodgment of the superior longitudinal sinus. At the outer part of the median line above the external notch is the foramen caecum. When open, it transmits a small vein ; above this is a sharp crest of bone, called the frontal crest, which gives attachment to part of the falx cerebri. Describe the nasal bone and give its articulations. It is a flat bone situated at the root of the nose, helping to form the bridge of the nose. It presents two surfaces and four borders. The external surface is concave from above downward and slightly con- vex from side to side. It is covered by the com- pressor nasi and pyramidalis nasi muscles. The internal surface presents a groove, the nasal groove, transmitting the nasal nerve. Its superior border articulates with the nasal notch of the frontal bone. ANATOMY. 3 og the anterior border articulates with its fellow ; and, on the inner edge of the inner border, it also articu- lates with the perpendicular plate of the ethmoid. The posterior border articulates with the superior maxillary bone ; its superior border is rough for articulation with the nasal notch of the frontal bone. It gives attachment to the cartilage of the nose. What is an aponeurosis ? It is a broad and expanded portion of a tendon, consisting of white fibrous tissue ; it may connect two bellies of muscles, as, occipital frontalis. Give origin and insertion of each of the muscles of the palpebral region. Four ; orbicularis palpebrarum, corrugator su- percilii, levator palpabrae and tensor tarsi. Orbic- ularis palpebrarum, orgin, — internal angular pro- cess of the frontal bone, and nasal process of the superior maxillary and tendon oculi, passes out- ward around the circumference of the orbit and is inserted, — some fibres into the tarsal ligaments, oftener, fibres form a complete ellipse ; the re- maining fibres blend in with the surrounding mus- cles. Corrugator supercilii ; origin, — from the inner extremity of the superciliary ridge, passing out to be inserted into the skin. Levator palpabrae ; origin, — under the surface of the lesser wing of the sphenoid above and in front of the optic foramen. It passes outward along the roof of the orbit, becoming aponeu- rotic, and it is inserted into the upper margin of the superior tarsal plate. Tensor tarsi ; origin. — from the crest and adjacent part of the orbital surface of the jio ANATOMY. lachrymal bone, extendiug across the lachrymal sac, it is divided into two tendons to be inserted into the tarsal plates. Mention the muscles of the tongue. Genio-hyo-glossus, hyo-glossus, stylo-glossus, palato-glossus, chondro-glossus. Give the origin, insertion and nerve supply of the styloglossus muscle. The origin from the anterior and outer side of the styloid process near its apex, passing downward and forward it is inserted into the side of the tongue. Nerve, the hypoglossal. Describe the middle cerebral artery. It is a large branch of the internal carotid, passes obliquely outward along the fissure of Sylvius and opposite the island of Reil, divides into terminal branches. It gives off the following branches : An- terolateral ganglionic^ inferior external frontal, par- ietotemporal, ascending frontal, ascending parietal. / Bound the superior carotid triangle (triangle of election). It is bound anteriorly and above by the posterior belly of the digastric and stylo-hyloid muscles ; bounded posteriorly by the anterior margin of the sterno-mastoid muscle ; anteriorly and inferior^, b} T the superior border of the omo-hyoid muscle. Describe the superior longitudinal sinus. It occupies the attached margins of the falx cere- bri ; begins at the foramen caecum of the frontal ANATOMY. j ii bone, passes vertically upward and backward, groov- ing the inner surface of the frontal and adjacent edges of parietal and inner sides of occipital bone, and teminates by opening into the torcular Herophili. It is triangular inform, narrow in front, gradually in- creasing in size as it passes backward. Describe the subclavian vein. It is a continuation of the axillary ; extends from the outer border of the first rib to the inner end of the clavicle, where it unites with the internal jugular to form the innominate vein. The subclavian vein lies anterior to the correspond- ing artery, and in the second part of its course is separated from the artery by the scalenus anticus muscle. Near the point where the external jugular empties a pair of valves is seen. Describe the submaxillary ganglion. It is a very small ganglion situated above the deep portion of the submaxillary gland, being connect- by filamants with the lower border of the lingual nerve. It also communicates with the corda tympani, and the s} T mpathetie plexus around the facial artery. Describe the ophthalmic nerve. It is the first division of the fifth, sensory in function arising, from the upper part of the Gasserian ganglion and leaves the cranium through the sphe- noidal fissure, and divided into three branches, — the frontal which supplies the eyebrow, forehead and nose; the lachrymal which supplies the lachrymal j 12 ANATOMY. gland; and the nasal which supplies the mucous membrane and septum of the nose. Name the arteries and nerves of the gums. The gums receive blood supply from the vas- cular mucous membrane covering them, and from terminal branches of the internal maxillary. The nerve supply is from the branches of the superior and inferior maxillary divisions of the fifth and fila- ments from Meckel's ganglion. What bones encase the brain and what is their relative position ? Occipital, two parietal, ethmoid, frontal, and sphenoid. The occipital bone is in the back part of the head ; the parietal bones form the top of the head ; the temporal bones are at the sides of the head ; sphenoid and ethmoid form part of the base of the skull ; the frontal bone forms the front part of the head and also enters into the formation of the orbit. What is the structural difference between an artery and a vein ? The main difference is in the middle coat of the vessels, which is much weaker in the veins than in the arteries, and which allows the veins to collapse when divided. Veins have valves, whilst the arteries have none. Describe the spinal column. The spinal column is a flexible column formed by a series of bones of which there are 33 in number. They are named, according to the position they occupy, cervical, dorsal, lumbar, sacral, and coccygeal. The column is situated in the median line at the posterior ANATOMY. j/j of the trunk ; its average length is seventy centime- tres (70 cm), and it contains the spinal cord. What are tendons and their function ? They are white glistening cords or bands com- posed almost entirely of white fibrous tissue ; they have but few vessels, no nerves, and serve to connect the muscles with the structures upon which they act. Describe the elbow joint and the manner of its lubrication It is a ginglymus articulation formed by the lower end of the humerus with the greater sigmoid cavity of the ulna and the head of the radius. It has four ligaments, viz : anterior, posterior, external and internal lateral. It is lubricated by the endothelial cells which line the synovial membrane and which secrete the synovial fluid. Describe the knee joint and its manner of lubri= cation. It is a ginglymus articulation formed by the con- dyles of the femur with the head of the tibia and the patella in front. It has fourteen ligaments, of which six are external and eight are internal. The liga- ments are as follows : Anterior or ligamentum patella ; posterior, or ligamenta Winslowii ; in- ternal lateral, two external lateral, capsular, an- terior crucial, posterior crucial, two semi-lunar fibro cartilages, transverse, coronary, ligamentum mucosum and ligamenta alaria. It is lubricated by the endo- thelial cells which line the synovial membrane and which secrete the synovial fluid. j 14 ANATOMY. What muscles are involved in respiration ? Diaphragm, external and internal intercostal, infracostals, pectoralis minor, rhomboideus, trapezius, serratus magnus. Describe the osseous structure which protects the thorax. It is an osseo-cartilaginous cage, formed by the dorsal vertebrae posteriorly, the ribs and costal cartil- ages laterally, and the sternum in front. Give the muscles of facial expression. Risorius, levator labii superioris alaeque nasi, orbicularis, depressor anguli oris, depressor labii in- ferioris, buccinator, platysma myoides, zygomaticus major and minor, levator labii superioris. Describe the joint in which the lower maxilla' works and the tissues constituting the joint. It is a double arthrodial joint. The parts enter- ing into the formation are : above, the anterior part of the glenoid cavity of the temporal bone and eminen- tia articularis ; and below, the condyle of the lower jaw. The ligaments entering into the formation of this joint are : internal and external lateral, stylo-maxillar}^ capsular, inter-articular fibro cartilage. Two synovial membranes are placed, one above and one below the fibro articular catilage. ( 1 ) The external lateral liga- ment is attached above to the outer surface of the zygoma and tubercle adjacent, and is inserted into the outer surface of the posterior border of the neck of the lower jaw. (2) The internal lateral ligament extends from the inner margin of the glenoid fossa, and spine ANATOMY. 3 J 5 of the sphenoid, to the inner aspect of the neck of the condyle. (3) The stylo-maxillary, extends from the apex of the styloid process of the temporal bone and is attached to the angle and posterior border of the ramus of the lower jaw, between 1 the masseter and in- ternal pterygoid muscles. (4) The capsular is attached to the circumference of the glenoid cavity. (5) The inter-fibro-articular cartilage is placed between the condyle of the jaw and the glenoid cavity. Name the bones of the head and face and give the articulation of the superior maxillary. Head : — Occipital, two parietal, two temporal, frontal, sphenoid, ethmoid. Face : — Two lachrymal, two malar, two turbinated, vomer, two superior max- illary, two palate, inferior maxillary, two nasal. The superior maxillary articulates with nine bones, viz : — frontal, ethmoid, nasal, malar, lachrymal, inferior tur- binated, palate, vomer, and with its fellow of the op- posite side. Give the origin, insertion, nerve supply and action of the gastrocnemius muscle. It arises by two heads, — the inner head, which is the larger and a little more posterior, arises from a depression at the upper and back part of the inter- nal condyle of the femur ; the outer head arises from the external condyle of the femur, the converging heads forming a fleshy belly to be inserted into the os calcis by the tendo Achilles. The nerve is the inter- nal popliteal, and the action is to extend the foot. What structures pass through the foramen mag= num. ji6 ANATOMY. The foramen magnum transmits the medulla oblongata and its membranes, spinal accessory nerves, the vertebral arteries, posterior spinal arteries and the occipito-axial ligaments. What is a mucous membrane, serous membrane ? Give example of each. A mucous membrane is a soft, velvety structure; it consists of epithelial cells which rest upon a basement membrane and secrete a fluid called mucus. It com- municates with the exterior of the body. A serous membrane is also a soft, velvety structure ; it consists of endothelial cells which rest upon a basement mem- brane, but does not communicate with the exterior of the body, e. g. mucous membrane of the mouth, serous membrane of the peritoneum. Name the principal muscles involved in mastica= tion and give the origin and insertion of two. Masseter, temporal, internal and external ptery- goid. The masseter muscle arises from the anterior two-thirds and inner surface of the zygoma and malar process of the superior maxillary, and is inserted into the angle, ramus and coronoid process of the lower jaw. The temporal muscle arises from the temporal fossa, and fascia, and is inserted into the anterior bor- der and inner surface of the coronoid process of the inferior maxillary bone. Describe the occipital bone and give its articu= lations. It is situated in the back part and the base of the cranium, and presents for examination two sur- ANATOMY. 3*7 faces, four borders and four angles. On its external sur- face there is a protuberance which affords attachment for the ligamentuni nuchas, also curved lines for the attachment of muscles. The internal surface is di- vided into a ridge and four fossae which lodge the occipital lobes of the cerebrum, and the hemispheres of the cerebellum. It also presents a protuberance similar to the one on the external surface, called the internal occipital protuberance. Posterior to the basilar process of the occipital bone is the foramen magnum. The occipital bone articulates with six bones, viz., two parietal, two temporal, atlas and sphenoid. Describe the shoulder joint with its integuments. It is an enarthrodial or ball and socket joint. The bones entering into its formation are two in num- ber, — the large head of the humerus which is received into the glenoid cavity of the scapula. The ligaments are the capsular, glenoid, transverse humeral, coraco- humeral. The capsular ligament encircles the glenoid cavity. The glenoid ligament is a fibro-cartilaginous rim attached to the margin of the glenoid cavity. The transverse humeral ligament is a broad band of fibrous tissue passing from the lesser to the greater tuberosity of the humerus. The coraco-humeral lig- ament strengthens the upper part of the capsular ligament. What muscles move the lower jaw ? Give origin and insertion. Temporal, masseter, digastric, genio-hyoid, mylo- hyoid, platysma myoides, external and internal ji8 ANA TO MY. pterygoid. The temporal arises from the temporal fossa and fascia, and is inserted into the coronoid pro- cess of the lower jaw. The masseter arises from the anterior two-thirds and inner surface of the zygoma and malar process of the superior maxillary, and is inserted into the angle, ramus, and coronoid process of the lower jaw. The digastric arises by two bellies- posterior, from the mastoid process of the temporal bone ; the anterior, from the fossa on the inferior maxillary near the symphysis, and is inserted into the central tendon, perforating the stylo-hyoid muscle and being bound down to the hyoid bone by aponeurotic loops. The genio-hyoid arises from the inferior genial tubercle of the inferior maxillary and is inserted into the hyoid bone. The mylo-hyoid arises from the mylo-hyoid ridge and is inserted into the hyoid bone. The platysma-myoides arises from the cellular tissue and integuments below the clavicle and is inserted into the chin and fascia of the lower jaw. The in- ternal pterygoid arises from the internal surface of the external plate of the pterygoid process, and is in- serted into the angle and inner surface of the ramus as high as the dental foramen. The external ptery- goid arises from the external surface of the external plate of the pterygoid process of the sphenoid bone, pterygoid ridges, and tuberosities of the palate and superior maxillary bones, and is inserted into a de- pression in front of the condyle of the lower jaw and inter-articular fibro cartilage. Describe the superior maxillary bone and give its articulations. ANATOMY. ji 9 The superior maxillary bone, with its fellow, forms a large part of the face. It presents for examination a body with nasal, malar, alveolar and palate pro- cesses. On ;the body may be noted four surfaces The facial, or anterior surface, presents a well-marked ridge of bone, the canine eminence. In front of the canine eminence is a depression, called the incisive fossa. Internally, this fossa is limited by a rounded border, which terminates in a process in the median line, called the nasal spine. Above the canine fossa is seen the infra-orbital foramen, which is the termination of the infra-orbital canal, transmit- ting the vessels and nerves of the same name. The posterior, or zygomatic surface, forms part of the zygomatic fossa. About its centre are seen several apertures leading into the posterior dental canals. Inferiorly, is the maxillary tuberosity, rough internally for articulation with the palate bone. By articulating with the palate bone, a posterior groove is converted into the posterior palatine canal. The superior, or orbital surface, forms part of the floor of the orbital cavity. Along the middle of this surface is seen a deep groove, called the infra- orbital groove, leading into a canal of the same name ; this is subdivided, transmitting the infra-orbital nerve and its anterior dental branches. The internal surface is unequally divided into two parts by the palate process ; the portion above the process forms part of the outer wall of the nasal fossa ; that below, forms part of the oral cavity. 3 20 ANATOMY. Superiorly, the opening into the antrum of High- more is seen. The malar process is a rough eminence, concave in front, forming part of the facial surface ; behind, the concavity forms part of the zygomatic fossa. The nasal process anteriorly is serrated for articula- tion with the nasal bone. Behind, it is smooth, articulating with the lachrymal bone. The surface presents superior and inferior turbinated crests ; the former articulating with the middle turbinated pro- cess of the ethmoid. On the posterior border is seen a groove, which assists in forming the nasal duct. The alveolar pro- cess, curved, presents the alveoli, or sockets for the teeth. The palate process forms part of the floor of the nasal cavity and the roof of the mouth. It presents, just behind the incisor teeth, a fossa, the anterior palatine fossa, at the bottom of which are seen four small foramina, two placed laterally, the foramina of Stenson, two antero- posterior^, the foramina of Scarpa. The fora- mina of Stenson transmit the anterior palatine arteries, whilst the foramina of Scarpa transmit the anterior palatine nerves. The superior maxillary bone articulates with the frontal, ethmoid, vomer, nasal, lachrymal, malar, palate, inferior turbinated, and with its fellow. Give origin, insertion, nerve supply, and action of the omo=hyoid muscle. ANATOMY. 3 21 It arises from the upper border of the scapula and transverse ligament (converts the supra-scapu- lar notch into a foramen), and passes forward and slightly upward across the lower part of neck, be- coming tendinous back af the sterno-mastoid muscle, and is bound down by a loop of the cervical fascia. The anterior belly forms an obtuse angle with its posterior belly, and passes upward to be inserted into the lower border of the body of the hyoid bone. Nerve supply — Branches from the loop of communi- cation between the descendens and communicans hypoglossi. Action — Depresses the hyoid bone, car- ries it backward and to the side. Give the origin, insertion, nerve supply and action of the genio=hyo=glossus muscle. It arises from the superior genial tubercles, passes backward and downward to be inserted into the under surface of the tongue, and body of the hyoid bone. It receives its nerve supply from the hypoglossal. Its action is to draw back the tip and create a dorsal transverse concavity, to draw the dor- sum at the back part forward, to protrude the tongue, and to assist in raising the hyoid bone. Describe the superior thyroid artery. It is the first branch given off from the external carotid just below the great cornu of the hyoid bone. It passes upward and inward, then, curving down- ward and forward in an arched and tortuous manner, proceeds to the upper part of the thyroid gland, pass- ing beneath the omo-hyoid, sterno-hyoid and sterno- thyroid muscles, and supplying them. It gives off 322 ANATOMY. the following branches ; hyoid, sterno-rnastoid, su- perior laryngeal and crico- thyroid. Describe the mylo=hyoid nerve. It is a branch of the inferior dental just as the nerve is about to enter the inferior dental canal ; it descends in a groove on the inner side of the jaw and supplies the mylo-hyoid, and anterior belly of the digastric muscles. Describe the os planum. It is a flat smooth surface situated on the outer surface of the lateral mass of the ethmoid bone. It is quadrilateral in outline, helping to form the inner wall of the orbital cavity. The superior border articu- lates with the frontal, the anterior border with the lachrymal, the inferior border with the superior maxilla and palate, and the posterior border with the sphenoid. riention the number of points of ossification of the inferior maxillary bone, and describe its development. Five centres of ossification. The lower jaw is developed principally from membrane, but partly from cartilage. The pro- cess of ossification commences earlier than in any other bone except the clavicle. The dentary centre of ossification appears between the fifth and sixth week in the membrane on the outer surface of Meckel's cartilage. The splenial centre appears in the mem- brane on the inner surface of Meckel's cartilage and from this centre the inner wall of the sockets of the teeth is formed. The anterior extremity of Meckel's ANATOMY. J2J cartilage becomes ossified forming the body of the bone on each side of the symphysis. A separate patch of cartilage appears at the condyle, and one at the angle, in each of which is a separate centre of ossifi- cation. The coronoid process is also ossified from a separate centre. At birth the bone consists of two halves united by fibrous symphysis, which ossifies during the first year. Give origin, insertion, nerve supply and action of the digastric muscle. This muscle consists of two fleshy bellies united by a rounded tendon. The posterior belly, longer than the anterior, arises from the digastric groove on the inner side of the mastoid portion of the temporal bone and passes downward, forward and inward. The anterior belly arises from a depression on the inner side of the lower border of the inferior maxillary, close to the symphysis, and passes downward and backward to join the posterior belly by a rounded tendon which perforates the stylo-hyoid muscle and is bound down to the hyoid bone by a fibrous loop lined by synovial membrane. The posterior belly is sup- plied by the facial nerve and the anterior belly by the mylo-hyoid nerve. Action : With the posterior belly fixed and the hyoid bone depressed, it acts by de- pressing the inferior maxilla. The attachment of the anterior belly being fixed, it raises the hyoid bone. Give the articulation of the ethmoid. It articulates with 15 bones, viz. : Sphenoid and frontal of the cranium, all the bones of the face ex- 3H A NATO MY. cept the two malar and inferior maxillary bone, and with the two. sphenoidal turbinated bones. flention the muscles of mastication and give their origin and insertion. Temporal : Origin, temporal fossae ; insertion, coronoid process and the whole length of the anterior border of the ramus of the inferior maxilla. Masseter : Origin, two heads, — the deep, from the inner inferior surface of zygomatic process of the temporal bone ; the superficial, from the zygoma and malar bone. Insertion, on the outer side of the ramus of the inferior maxilla. External pterygoid : Origin, two heads. — the long head, from the pte^goid ridge and under sur- face of the great wing of the sphenoid bone ; the short head, from the ^external surface of the pterygoid plate of the sphenoid bone. Insertion, — into a fossa on the anterior border of the neck of the condyle of the lower jaw and interarticular fibro cartilage of the temporo-maxillary articulation. Internal pterygoid : Origin, from the pteiygoid fossae ; insertion, into the inner side of the ramus and angle of the inferior maxilla. Buccinator : (Is sometimes described as a muscle of mastication). Origin, from the alveolar process above the upper and below the lower molar teeth and the anterior border of the pterygo-maxillary ligament. Insertion, into the orbicularis oris muscle at the angle of the mouth. ANATOMY. 325 Mention the muscles attached to the hyoid bone. Sternohyoid, thyro-hyoid, omohyoid, aponeurosis of digastric, stylo-hyoid, mylo-hyoid, genio-hyoid, genio- hyo-glossus, chondro-glossus, hyo-glossus, middle constrictor of the pharynx, and sometimes a few fibres of the inferior lingualis. Describe the aorta. It is this main artery that conveys the pure blood to the tissues of the body for nutrition. This vessel commences at the upper part of the left ventricle, as- cends a short distance to the right of the vertebral column, then arches backward and to the left side over the root of the left lung, and then descends into the thorax on the left side of the vetrebral col- umn, passes through the aortic opening in the diaph- ragm, enters the abdominal cavity, and terminates op- posite the lower border of the fourth lumbar vertebra. Here it divides into the right and left common iliac arteries. It is divided into the ascending aorta, the arch of the aorta, the descending aorta, thoracic aorta and abdominal aorta. Describe the superior vena cava. It receives the blood from the upper half of the body and conveys it to the heart. It is seven or eight centimetres in length and is formed by the junction of the two innominate veins. It commences immedi- ately below the cartilage of the first rib, close to the sternum on the right side, enters the pericardium, and empties into the right auricle of the heart. Describe the fissure of Rolando and give its location. j 26 ANATOMY. It is situated about the middle of the outer sur- face of the cephalic hemisphere. It commences near the longitudinal fissure and terminates a little above the horizontal limb of the fissure of Sylvius, running obliquely downward and forward. Describe the inferior maxillary nerve. The inferior maxillary nerve is formed by two parts, viz.: the entire motor root of the fifth nerve, and a group of fibers sent from the sensory root through the Gasserian ganglion. These bundles pass through the foramen ovale and unite on the outside of the cranium to constitute a trunk which in turn speedily divides into an anterior and a posterior portion. The anterior, the smaller, and which receives nearly the whole of the motor root, divides into branches that supply the muscles of mastication — the masseter, deep temporal, buccal and pterygoid. The posterior trunk which is the largest and for the most part sensory, but which receives a few fila- ments from the motor root, divides into three branches, auriculotemporal, lingual, and inferior dental. Mention the muscles attached to the sphenoid bone. Temporal, external pterygoid, internal pterygoid, superior constrictor, tensor palati, levator palpebrae superioris, superior rectus, internal rectus, inferior rectus, superior oblique, and external rectus. Describe the Vidian nerve. The vidian nerve is formed by the union of the large superficial petrosal branch of the facial and the ANATOMY, 3 2 7 large deep petrosal branch of the carotid plexus ; they join to form the nerve trunk in the cartilage which fills in the middle lacerated foramen. The nerve then passes forward through the vidian canal and joins the posterior angle of Meckel's ganglion, which is located in the spheno-maxillary fossa. flention the branches of the occipital artery. Muscular, sterno-mastoid, auricular, meningeal and arteria princeps cervicis. Describe the inferior maxillary bone. It is situated at the anterior and inferior part of the face and is the only movable bone of the skull. Presents for examination a horizontal part and two vertical portions. The horizontal part or body is shaped like a horse-shoe, presenting an external and internal surface, and two borders, — superior and inferior. The external surface presents the following points: — In the median line, the symphysis ; on each side of the symphysis, the incisive fossa, mental fora- men; external oblique line. Internal surface. — In the median line, four genial tubercles situated in pairs, on each side the lingual fossa, the internal oblique line, digastric de- pression, and the sub-maxillary fossa. The superior border or alveolar process presents sockets for the reception of eight teeth. The inferior border is rounded and smooth. Anteriorly is the attachment of the platysma, and j 2 8 ANATOMY. near the angle is a groove for the facial artery. The ramus is quadrilateral, and presents two surfaces and four borders. The external surface is rough for the insertion of the masseter muscle. The internal sur- face, presents in the center, the beginning of the in- ferior dental canal, a spine projecting from it, the lingula, for attachment of the internal lateral ligament of the lower jaw ; near the angle, a rough surface for insertion of the internal pterygoid muscle. The anterior border gives attachment in part to the temporal muscle ; and the posterior border gives attachment to the stylo-maxillary ligament ; while the superior border presents two processes separated by the sigmoid notch, the coronoid and condyloid. The coronoid process is sharp and thin and gives insertion to the temporal muscle. The condyle is an ovoidal process with a constricted portion called the neck. Its longest diameter is transversly or obliquely set on the neck. On the outer part of the neck is a pro- cess for the insertion of the tendon of the external pterygoid muscle. The inferior maxillary articulates with the two temporal bones. Describe the palatoglossus muscle. Give origin, insertion and nerve supply. Origin : From the anterior surface of the soft palate on each side of the uvula, it passes downward, forward and outward, and is inserted into the side of the tongue. Nerve supply : From the pharyngeal plexus formed by the vagus and glosso-pharyngeal nerves. ANATOMY. j 2 g Describe the facial surface of the superior maxil= lary bone and give the centre of ossification. It is slightly concave, presents above the incisor teeth the incisive fossae, for origin of the compessor nasi muscle ; to one side is the canine eminence, showing position of canine tooth ; a little above is the canine fossae, for the origin of the levator anguli oris muscle ; above this, is the infra orbital foramen through which passes the infra orbital vessels and nerves. Still more superiorly is a rough ridge for attachment of the lavator labii superioris muscle. The centres of ossification are four in number all of which are deposited in membrane. One for the facial surface, one for that portion about the infra orbital canal, one for the palatine process and one for the alveoli of the incisor teeth. Describe the internal jugular vein. It collects the blood from the interior of the cran- ium, and from the superficial portions of the face and neck. It begins at the jugular foramen, being formed by the union of the lateral and inferior petrosal sin- uses. It descends in the carotid sheath to the outer side of the internal carotid and common carotid arter- ies, and at the root of the neck, joins the subclavian vein to form the innominate vein. What muscles control the soft palate ? Tensor palati and levator palati. What are the terminal branches of the external carotid artery ? Temporal and internal maxillary. j jo ANA TO MY. Describe the maxillary sinus, (or antrum of High= more). It is a triangular shaped cavity situated in the body of the superior maxillary bone. Its base is toward the nasal' cavity, and its apex points towards the molar process. The roof is formed by the orbital surface of the bone, the anterior wall by the facial surface, and the floor by the alveolar process. It is sometimes divided into compartments by osseous septa. Extending along the posterior wall, is the pos- terior dental canal which transmits the posterior dental vessels and nerves ; and on the anterior surface is the anterior dental canal for its vessels and nerves. Some- times there are conical projections in the floor of the cavity as the result of the roots of the first and second molar teeth. The opening in the base is closed in by the palate, ethmoid and inferior turbinated bones, leaving a small orifice at the anterior and superior part to communicate with the middle meatus of the nose. What muscles depress the lower jaw ? Digastric, stylo-hyoid, mylo-hyoid and genio- hyoid. / What forms the circle of Willis ? It is formed by nine arteries, viz. : — Two pos- terior cerebral, two posterior comimmicating, two in- ternal carotid, two anterior cerebral, and one anterior connecting. Describe the gustatory nerve. It is sometimes called the lingual nerve and is a ANATOMY. 33 r branch of the inferior maxillary division of the fifth. It passes down along the pterygoid muscles and then forward to the tongue. At the angle of the jaw, it is joined by the chorda tympani, which gives it special sense fibres. It supplies the mucous membrane and papillae of the anterior two-thirds of the tongue. What are the articulations of the malar bone ? With four bones,— -frontal, sphenoid, superior maxillary, and temporal. Name articulations of the occipital bone. With six bones, ---two temporal, two parietal, sphenoid and atlas. Describe the inferior maxillary artery and name its branches. It is generally called the inferior dental artery.lt is a branch of the first part of the internal maxillary ar- tery, and passes down and enters the inferior dental canal ; as it enter, it gives off the mylo-hyoid branch ; continuing downward, it turns horizontally forward at the angle occupying the canal in the body of the bone to one half inch in front of the mental foramen ; then, turning back, it forms a loop where the incisive branches are given off, and comes out of the mental foramen. After emerging, it gives off the mental and labial arteries. Name the muscles of the soft palate. Palato-glossus, palato-pharyngeus, azygos mus- cle, levator palati, tensor palati. What artery supplies the tongue with blood ? The lingual. 33 2 ANATOMY. Name the articulation of the temporal bone. Parietal, occipital, malar, sphenoid, and inferior maxillary. Name the muscles of the tongue and their attach- ments. Genio-hyo-glossus, hyo-glossus, stylo-glossns, palato-glossus, chondro-glossns : Origin, from the superior genial tubercle ; insertion, — hyoid bone and side of tongue. Hyo-glossus. {Origin, — great cornu of hyoid bone. Insertion, — side of tongue. f Origin, — styloid process of the Styly-glossus. \ temporal. j Insertion, — side of tougue, near [ the dorsal surface. f Origin, — base of lesser cornu of m. j i ! hyoid bone. Lnondro-glossus. -< T J ,, , .^ . . & j Insertion, — blends with intrinsic [_ muscular fibres of the tongue. {Origin, — soft palate on each side of uvula. Insertion, — side of tongue. Palato-glossus. Describe the lingual artery and give its branches. It is a branch of the external carotid, and arises between the facial and the superior thyroid. Passes upward and inward to the greater cornu of the hyoid bone and forward, crossed by the hypo-glossal nerve beneath the digastric, stylo-hyoid, and hyo-glossus muscles ; then horizontally forward to the tip of the ANATOMY. jjj under surface of the tongue under the name of the ranine artery. Its branches are four, viz. : — hyoid, dorsalis linguae, sublingual and ranine. Describe the occipito-frontalis. It arises from the superior curved lines of the oc- cipital bone and mastoid portion of the temporal, forms a fleshy belly about two inches in length ; then be- comes aponeurotic, passing over the vertex of the skull, and, terminating at the frontal bone into an an- terior belly of muscular fibres, its insertion is formed by blending with the pyramidalis nasi, orbicularis palpebrae, and corrugator supercilii muscles. Its action is to raise the eyebrows and produce transverse wrinkles on the forehead. Nerve supply : The frontal portion is supplied by the temporal branch of the facial ; the posterior portion, by the posterior auricular branch of the facial. What muscles control the eye ? Superior oblique, inferior oblique, internal rec- tus, superior rectus and inferior rectus. Which artery is the longest, the external or in- ternal carotid ? Internal carotid. Mention the bones of the cranium. Occipital, sphenoid, ethmoid, two temporal and two parietal. flention the muscles of the pharynx. Inferior constrictor, middle constrictor, superior 334- ANATOMY. constrictor, stylo-pharyngeus. palato-pharyngeus, and salpingo-pharyngeus. Describe (a) the facial vein, (b) the internal max= illary vein. The facial vein commences at the side of the root of the nose, being a continnation of the angular vein. It lies posterior to the facial artery, and, fol- lowing a less tortuous canal, it passes downward and backward, and then over the body of the lower jaw. It lies with the facial artery ; continuing obliquely outward and backward, it unites with the anterior di- vision of the tempero-m axillary vein, forming the com- mon facial vein, which enters the internal jugular. (b) The internal maxillary vein is a vessel which accompanies the internal maxillary artery and is of considerable size. It receives the following veins : Middle meningeal, the deep temporal, the pterygoid, the masseteric, the buccal, alveolar, in- ferior dental and some palatine veins. The trunk of the vein passes backward behind the condyle of the inferior maxillary bone, and unites with the temporal vein, forming the tempero-maxillary vein. Give the branches of the external carotid artery. Superior thyroid, lingual, facial, occipital, pos- terior auricular, ascending pharyngeal, temporal and internal maxillary. What muscles have their origin in the styloid process ? Stylo-pharyngeus, stylohyoid, and stylo-glossus. Give the origin and insertion of the sterno=rnas= toid muscle. ANATOMY. 335 It arises by a round tendon from the anterior part of the front of the sternum, and by a flat tendon from the inner superior border of the clavicle, the two heads converging about an inch above the origins to form a strong muscle which passes obliquely up- ward and backward to be inserted into the mastoid process of the temporal bone. Describe the tensor palati. It arises from the scaphoid fossa of the sphenoid bone and the margin of the Eustachian tube, passes at first downward, then becoming tendinous, reflected around the hamular process of the internal pterygoid plate, and extends horizontally to be inserted into the soft palate, its fibres blending with its fellow of the opposite side ; it is also attached to the transverse ridge of the horizontal portion of the palate bone. Nerve supply. — A branch from the pharyngeal plexus. Its action is to make the palate tense. What bones articulate with the vomer? Sphenoid, ethmoid, two palate and two superior maxillary. Describe the sphenoidal fissure. It is situated in the posterior part of the orbital cavit}' between the greater and lesser wings of the sphenoid bone. It is bounded above by the lesser wing, below by the greater wing, internally by the body, and is converted into the foramen lacerum arteritis by the articulation of the frontal bone. It transmits the third and fourth ophthalmic divisions of the fifth and sixth cranial nerves, some filaments jj6 ANATOMY. of the cavernous plexus of the sympathetic system, a branch of the orbital artery to supply the dura mater, the recurrent branch of the lachrymal artery, ophthalmic vein, and processes of the dura mater. Describe the glenoid fossa. It is situated between the anterior and middle roots of the zygoma of the temporal bone. It is bounded anteriorly by the anterior root and eminentia articularis ; above and externally, by the middle root and auditory process ; posteriorly, by the tympanic plate. It is divided into two parts by the Gasserian fissure ; the anterior part receives the condyle of the lower jaw, and the posterior part receives the parotid gland. riention the bones of the face. Two nasal, two superior maxillary, two lach- rymal, two malar, two inferior turbinated, two palate, vomer, and inferior maxillary. What nerve and artery passes through the fora= men ovale of the sphenoid bone ? The inferior maxillary division of the fifth nerve, and the small meningeal branch of the first part of the internal maxillary artery. Mention the muscles attached to the inferior max= illary bone. Fifteen pairs, viz., levator men ti, depressor labii in- ferioris, depressor anguli oris, platysma myoides, buc- cinator, masseter, orbicularis oris,genio-hyo-glossus, genio-hyoid, mylo-hyoid, digastric, superior constrict- ANATOMY. 337 or, temporal, internal pterygoid, and external ptery- goid. Mention the principal veins of the head and neck. The principal veins of the head are the frontal, angular, facial, temporal, internal maxillary, temporo- maxillary, occipital ; of the neck, external jugular, internal jugular, anterior j ugular and vertebral. What muscles are attached to the basilar process of the occipital bone ? Rectus capitis anticus, major and minor, and superior constrictor of the pharynx. Give the boundary of the anterior triangle of the neck. It is bounded superiorly by the inferior border of the lower jaw, and a line extending from the angle of the mastoid process of the temporal bone. Posteriorly, by the anterior margin of the sterno-mastoid muscle. Anteriorly, by the median line of the neck. flention the muscles attached to the outer surface of the malar bone. Levator labii superioris, zygomaticus major and minor. Describe the sigmoid notch. It is situated between the condyloid process and coronoid process of the superior border of the inferior maxillary bone. It transmits the masseteric vessels and nerves. Mention the branches of the maxillary portion of the internal maxillary artery. 33 8 ANATOMY. Tympanic, great or middle meningeal, small meningeal, and inferior dental. Mention the branches of the posterior auricular artery. Stylomastoid, anricnlar, mastoid, muscular and glandular. Give the branches of the internal maxillary artery. This artery is divided into three parts, namely : Maxillary, pterygoid and spheno-maxillary. C Tympanic, r Deep temporal, Maxillary \ Middle meningeal, Pterygoid \ Buccal, portion: / Sma11 meningeal, portion: ) Pterygoid, v Inferior dental. V. Masseteric. C Alveolar, \ Infraorbital, Spheno-maxillary j Descending palatine, portion: \ Vidian, .' Pterygo-palatme, t Spheno-palatine. Describe the Gasserian ganglion. It is found on the fifth nerve and is situated in the Gasserian depression on the apex of the petrous portion of the temporal bone, between the bone and dura mater. It is entirely sensory, and, as the motor root passes beneath it, it gives off three large branches or divisions, — ophthalmic, superior maxillary and inferior maxillary. Give the origin and insertion of the sternothyroid muscle. It arises from the posterior surface of the upper part of the sternum and cartilage of the first rib, and is inserted on the oblique line on the side of the ala of the thryoid cartilage. A NATO Ad Y. 339 Describe the myIo=hyoid muscle, giving its origin and insertion. This muscle forms with its fellow the floor of the mouth. It arises from the whole length of the mylo- hyoid ridge of the inferior maxillary bone and is in- serted into the hyoid bone, meeting its fellow in a median raphe. Nerve, the mylo-hyoid, a branch of the inferior dental. Its action, assists in carrying the tongue upward and forward. /lention the orbital branches of the ophthalmic artery. Lachrymal, supra-orbital, posterior ethmoidal, an- terior ethmoidal, palpebral, frontal, nasal, muscular, ciliary. Describe the temporal fossa. It is situated at the side of the skull, and is bounded above by the temporal ridge ; in front by the frontal, malar, and great wing of the sphenoid ; ex- ternally, by the zygomatic arch. Below, it is sepa- rated from the zygomatic fossa by the pterygoid ridge, seen on the outside of the great wing of the sphenoid bone. This fossa is formed by parts of five bones, viz. : Sphenoid, frontal, parietal, temporal and malar. It gives origin to the temporal muscle. Describe the great wing of the sphenoid bone. It projects from the sides of the body and presents three surfaces, — superior, anterior and ex- ternal. 340 ANATOMY. Superior surface : Smooth and concave, and helps to form the middle fossa of the cranial cavity ; it contains the following foramina : Rotundum, ovale, vesalii, spinosum. Anterior surface : Is quadrilateral, smooth, con- cave and helps to form the outer wall of the orbital cavity. The superior border articulates with the frontal, the external border articulates with the malar, the inferior border forms the posterior boundary of the spheno-maxillary fossa, and the internal border helps to form the sphenoidal fissure. External surface : Helps to form two fossae, temporal and zygomatic, which are separated by the pterygoid ridge. PHYSIOLOGY AND HYGIENE. Give the sources of saliva and its chemical func- tions and otherwise. Saliva is the secretion of the parotid, submaxil- lary and sublingual glands. It contains a ferment, ptyalin, which converts starch into maltose. The saliva facilitates speech by moistening the mucous membrane of the mouth ; and on account of its con- tained mucin facilitates deglutition by lubricating the bolus of food. By dissolving some of the solids in the food it allows them to be tasted. Where and how are the products of digestion fin- ally incorporated into the tissues ? The digested food is absorbed mainly by the villi of the small intestines. The water, soluble salts, glucose and peptones are passed through the columnar epithelium of the villi into the capillaries. These capillaries are radicals of the portal vein, and through this vein the products are carried to the liver. The blood of the liver passes out through the hepatic vein into the inferior vena cava and thus into the general circulation. The peptones during their passage through the columnar epithelium are converted into albumens and globulins. The digested fat passes through the columnar epithelium of the villi into the central lymphatic vessel or lacteal. These lacteals 342 PHYSIOLOGY AND HYGIENE. carry the absorbed fats to trie thoracic duct, which in turn empties thein into the left sub-clavian vein, and thus into the general circulation. Describe the physiological process that takes place in the kidneys. The kidneys are compound tubular glands secret- ing urine. The tubules commence in the Malpighian corpuscles in the cortex. After leaving these the tubules become convoluted, then pass down as the loops of Henle, again become convoluted, and finally empty into the collecting tubules. The convoluted portions are lined with rodded epithelium, and it is by these cells that the urea ;s picked out of the blood. All the substances found in the urine are waste products cir- culating in the blood, and these the epithelium picks out from the blood. The one exception to this is hippuric acid which is formed by the kidney cells. Describe the stomach and its secretions. The stomach is the ovoid dilation of the gastro- intestinal tract ; and is a muscular sack lined inside with mucous membrane, and outside with a serous membrane. The food enters from the oesophagus at the cardiac orifice, and'passes out into the duodenum at the pyloric orifice. The stomach has two curva- tures, the upper, or lesser curvature, and the lower, or greater curvature. That portion of the stomach, lying towards the spleen and forming a part of the greater curvature, is called the fundus. The stomach has four coats : serous, or outer ; muscular, of which there are three distinct layers, circular, longitudinal PHYSIOLOGY AND HYGIENE- 3 4 3 and oblique; submucous; and mucous, imbedded in which we have the tubular glands that secrete the gastric juice. The gastric juice is a limped, acid secretion, specific gravity 1005, containing salts, hydrochloric acid (.2%), and two ferments, pepsin and rennin. About ten pints are secreted daily. How is the skin kept moist and the cuticle pliable ? The skin is kept moist by the sweat, and the cut- icle pliable by the sebaceous secretion. What are the sources of heat in the body ? Heat is produced in the body by katabolism prin- cipally in the muscular and glandular tissues. Trace the circulation of the blood once around its course beginning at the right auricle. The blood enters the right auricle from the sup- erior and inferior vena cavas, thence through the right auriculo-ventricular or tricuspid valve into the right ventricle , past the pulmonary semilunar valve into the pulmonary artery to the capillaries of the lungs ; from the lungs it is carried back through the pulmonary veins to the lejl auric le, past the left auriculo-ventri- cular or mitral valve into the left ventricle, through the aortic semilunar valve into the aorta and its branches to the capillaries of systemic circulation, and from these it is carried back to the heart by the systemic veins. What is waste, and by what organs is it elimi- nated from the system ? 344 PHYSIOLOGY AND HYGIENE. Waste is products of metabolism of no further use to the organism. Waste is eliminated by the lungs, kidneys, skin and liver. In what various ways is the loss by waste re- stored ? By food, water and respiration ; the blood acting as a medium of exchange. Describe the mechanical process by which the blood receives oxygen. The blood receives its oxygen in the lungs where the capillaries containing venous blood are separated from the oxygen of the air by a single layer of pave- ment epithelium. Three factors are concerned in the absorption of oxygen : mechanical law of pressure of gases, chemical affinity between hemoglobin and oxygen, and the vital activity of the epithelium of ' the air vesicles. By what special fluid is nourishment to the tissues delivered, and how ? By the circulating blood, by osmosis through the capillary walls. Describe fully the preparation of pabulum for the blood. The starches are converted by ptyalin of saliva and amylopsin of pancreatic juice into maltose. Maltose and cane sugar are converted into glu- cose by the invertin of succus entericus. Caseinogen is converted into casein by therennin of gastric juice, and the milk curdling ferment of pancreatic juice. PH YSIOL OGY AND HYGIENE. 345 The proteids are changed into proteoses and peptones by the pepsin of gastric juice and the trypsin of pancreatic juice. The fats are split up into fatty acids and glycerine, saponified and emulsified by the steapsin of pancreatic juice and by the bile. The digested food is then absorbed by the villi of the small intestines. The fats are carried by lacteals to the thoracic duct ; and the glucose, water, soluble salts and peptones are carried by portal vein to the liver, the peptones being changed into native proteids while passing through the epithelium of the villi. What is the medulla oblongata ? Give a short description. The medulla oblongata is that portion of the cen- tral nervous system between the upper end of the spinal cord and the lower boundary of the pons Varolii. It is pyramidal in shape with the base upward, and is about one inch long, three fourths of an inch wide and half an inch thick. Anteriorly is seen the anterior median fissure, the olivary bodies, and the anterior pyramids. The posterior surface of the medulla forms part of the floor of the fourth ventricle bounded on each side by the diverging posterior columns of white mat- ter. Laterally we find emerging the cranial nerves from the sixth to the twelfth inclusive. In structure we find that it is made up of gray and white matter. 34-6 PHYSIOLOGY AND HYGIENE. The gray mattter is cut up into small masses by the motor and sensory decussations. These masses of gray matter form the nuclei for most of the cranial nerves. Describe the mechanism of the heart. The heart is a hollow muscular organ divided in- to four cavities, two on the right side and two on the left. Between the two sides there is no communica- tion. The right side receives venous blood and forces it into the pulmonary circulation. The left side re- ceives arterial blood and forces it into the general, systemic or greater circulation. The two auricles, contracting simultaneously toward the end of ventri- cular diastole, force the blood into the ventricles. The ventricles then contract, the auriculo-ventricular valves are closed, and the blood is forced into the arteries. The ventricles then relax and the blood flows in from the auricles, the auriculo-ventricular being open. The blood tends also to regurgitate into the ventri- cles from the arteries, but is prevented by the closure of the semilunar valves. The heart has been likened to a force pump, but it is also a suction pump, for dur- ing diastole, there is a negative pressure in the vent- ricles due to the elasticity of the muscular wall tend- ing to produce a vacuum. As to the nervous mechanism of the heart, we find in the medulla the cardio inhibitory aud the cardio accelerating centres. The efferent nerve from the cardio-inhibitory centre to the heart is the vagus PHYSIOLOGY AND HYGIENE. 347 or pneumogastric ; the efferent from the cardio-accele- rator centre is the accelerator branch of the sym- pathetic system. These nerves end in ganglionic masses in the heart. There is also an afferent nerve from the heart called the nervous depressor of the Cyon and Ludwig. When there is danger of rupture of the heart from over-pressure, it is irritated and carries an im- pulse to the vasomotor centre that depresses its tonus and lowers the blood pressure. Describe the pancreas, and the character and func= tions of its secretion. The pancreas is a tongue-shaped organ about six inches long, weighing about two ounces and situated back of the stomach. It is sometimes called the ab- dominal salivary gland. The duct enters the duodenum about an inch and a half below the pylorus. The bile duct joins with it just before it opens into the duodenum. The pancreatic juice is a transparent, viscid, alkaline fluid, specific gravity 1012. There are about eight ounces secreted daily. It contains salts, espe- cially sodium salts and four ferments. Amylopsin converts starch into maltose. Trypsin converts proteids into peptones and even into lower bodies, leucin, tyrosin and arginin. Steapsin splits up the fats into fatty acids and glycerine. The fatty acids combine with the alkalies present to form soap and this aids the emulsification of the rest of the fat. There is also a milk curdling ferment. 3*8 PHYSIOLOGY AND HYGIENE, The pancreas has also an internal secretion as extirpation of the organ causes diabetes. In what way does the blood lose material ? By osmosis through the capillary walls into the tissues ; by excretion from the lungs, skin, kidneys and liver, and by osmosis into gastro-intestinal canal as in the watery stool following saline cathartics. Describe fully the white corpuscles of the blood, and give their origin. The white corpuscles at rest are globular nu- cleated masses of protoplasm about 1-2500 of an inch in diameter. There are a number of varieties. The small mononuclear or lymphocyte, the large mono- nuclear or transitional, the poly-morphonuclear, which is the most abundant, and the eosinophite containing coarse granules readily stained with eosen. The leucocytes have the power to throw out pseu- dopodia, or, it is called amoeboid movement. They originate in the lymphatic tissue and in the marrow of bones. What is the cerebro=spinal axis, and what is its function ? The cerebro-spinal axis is that portion of the nervous system consisting of spinal cord, medulla, pons varolii, crura cerebri, basal ganglia, cerebrum and cerebellum. Its function is to receive afferent impulses and to send out as the result of these efferent impulses, to keep the body in normal condi- tion, and through the cerebrum presides over thought, volition and perception. PHYSIOLOGY AND HYGIENE. 349 What is the purpose of the lymphatic system and how fulfilled ? The liquid portion of the blood osmoses through the capillary walls into the tissue. This diluted blood plasma is called lymph and is carried by the lymphatics back to the general circulation through the thoracic duct. They also carry absorbed material as the fat from the intestines, into the general circu- lation. The secretion of some of the ductless glands is emptied into the blood through its lymphatics. The cells formed in the lymph glands become leucocytes. What chemical exchange is effected in the lungs during respiration ? Oxygen is obsorbed by the blood. Carbon- dioxide, nitrogen, water and very small quantities of organic volatile principles are thrown off. How is the normal temperature of the human body maintained ? The normal temperature of the body is main- tained at about 98.4 ° F., by the proper balancing of heat production and heat dissipation. The production and dissipation of heat are controlled by the thermo- taxic centres of the nervous system. These include the thermolytic, thermogenic and thermoinhibitory centres. Describe the process of deglutition and name the glands where secretions are an essential aid in the process. Deglutition is the act of swallowing or passing of the food from the mouth into the stomach. There j So PHYSIOL OGY AND HYGIENE. are in this act three stages, buccal, pharyngeal and oesophageal. The first is voluntary, the last two are involuntary. The bolus of food is forced by the tongue froni the mouth into the pharynx. The muscular wall of which contracting from above downward forces the bolus into the oesophagus. A peristaltic wave of con- traction then forces the bolus through the oesopha- gus into the stomach. Thus the deglutition of solids is a peristaltic act. But liquids are squirted through the pharynx and oesophagus with bulb syringe effect by contraction of the mylo-hyoid muscle. The centre of deglutition is in the medulla. It receives afferent impulses through the trifacial and glosso-pharyngeal nerves, and gives off efferent impul- ses through the inferior maxillary division of the trifac- ial and glosso-pharyngeal and vagus. The glands whose secretions aid deglutition are the salivary especially the sub-maxillary and sub- lingual ; also the mucous glands of the mucous mem- brane of the mouth, pharynx and oesophagus. Name the digestive secretions, mentioning the principal action of each upon food. Saliva, gastric juice, pancreatic joice, bile and succus entericus are the digestive secretions. Saliva converts starch into maltose. Gastric juice converts proteids into peptones, and caseinogen into casein. Pancreatic juice converts preteids into peptones, starch into maltose, splits up the fats into fatty acids PHYSIOLOGY AND HYGIENE. 35 1 and glycerine, and converts caseinogen into casein. Bile emulsifies fats and prevents excessive action of bacteria. Succus entericns converts maltose and cane sugar into glucose. Give the apparent origin and general distribution of the pneumogastric nerve. Mention some of the organs whose action it influences. The superficial origin of the pneumogastric is from the groove on the lateral surface of the medulla between the olivary and restiform bodies. It is dis- tributed to the pharynx, larynx, oesophagus, heart, lungs, stomach and to the abdominal sympathetic system. It is the motor nerve to the pharynx ; mo- tor and sensory to the larynx ; motor, sensory and respiratory to the lungs ; motor, sensory and secre- tory to the stomach ; cardio inhibitory to the heart, and secretory to the pancreas. Describe the liver, its secretion and the function thereof. The liver is the largest gland in the body weigh- ing about four pounds, and measuring transversely about twelve inches, antero-posteriorly about seven inches, and at its posterior part is about three inches thick. It is situated principally in the right hypochon- driac region, but extends through the epigastrium into the left hypochrondriac region. It is divided by five fissures into five lobes, the largest of which is the right lobe. The most impor- 352 PHYSIOLOGY AND HYGIENE, tant fissure is the transverse ; for through this the blood enters the liver through the portal vein, and hepatic artery, and passes out through the hepatic vein. The bile also passes out through the hepatic duct through this fissure. The secretion of the liver is bile. Bile is a reddish yellow, or reddish green, alka- line, viscid, bitter liquid with a specific gravity of about 1020, There are about two or two and half pints secreted daily. It contains among other substances bilirubin, biliverdin, taurocholate and glycocholate of sodium, cholesterin, mucin and inorganic salts. The bile neutralizes the acid chyme precipitat- ing the pepsin, it emulsifies fats and aids in their absorption ; it increases peristalsis ; it is a slight an- tiseptic ; and contains waste products thrown off by the liver. State the average proportion of carbon=dioxide in iooo parts of atmosphere. What should be the maximum limit of carbon=dioxide in school rooms. Four parts of carbon-dioxide to ten thousand of air is the normal. The maximum limit of carbon-dioxide in a school room should be .05%. flention the nutritive fluids of the body. Blood, lymph and chyle. What conditions affect the body temperature ? All conditions affect the body temperature that destroy the balance between heat production and heat dissipation . PHYSIOLOGY AND HYGIENE, 353 Among these you have muscular exercise, diges- tion, prolonged exposure to extremes of temperature, shock (mental or physical), hysteria, drugs (as anti- pyrin, chloral hydrate and atropine), toxins of bac- teria, injection of peptones and ptomaines, irritation of any one of the thermotaxic centres. Give the composition of the pancreatic secretion. According to Halliburton you have 97.6% of water; 1.8% of organic matter of which the most im- portant are the ferments ; and .6% inorganic salts, among which are sodium chloride, sodium phosphate and potassium chloride. Give the properties of pancreatic juice, and state its reaction. Where does the pancreatic juice enter the intestine. The pancreatic juice is a colorless, transparent, viscid, alkaline fluid with a specific gravity of 1012. It contains four ferments ; trypsin, amylopsin, steap- sin and a milk-curdling ferment. The pancreatic juice enters the intestine through an opening in the posterior surface of the duodenum about its middle. Give the composition of blood, and state the use of each component part. The blood is composed of sixty parts of plasma or liquor sanguinis, and forty parts of corpuscles. The plasma is the liquid portion and contains about ten per cent of solid matter of which four-fifths are proteids. The solid matter is made up of serum albumen, serum globulin, fibrinogen, salts, glucose, fats and extractives. 354 PHYSIOLOGY AND HYGIENE. There are two kinds of corpuscles, red and white. The red corpuscles are the more numerous, the proportion being five hundred red to one white. The principal substance in the red corpuscle is the hemo- globin. The white corpuscles have amoeboid movement, and have a phagocytic action. By their disintegration fibrin ferment is formed. The red corpuscles carry the oxygen to the tissues. The fibrinogen clots after leaving the vessel and thus stops bleeding. The plasma carries the absorbed food to the tissues and the waste products to the excretory organs. The blood also keeps the various parts of the body at a fixed temperature. The function of the blood plates is not known. State the difference between the vasoconstrictor nerves and the vaso=dilator nerves. The vaso-coristrictors, when stimulated, decrease the calibre of the arterioles by causing a contraction of the muscular fibres in the middle coat of the vessels. The vaso-dilators, when stimulated, increase the calibre of the arterioles by inhibiting or decreasing the tonus of the local vaso-motor ganglia in the mus- cular wall. Define voluntary muscle ; involuntary muscle. Give example of each. The voluntary muscles are those under the con- PHYSIOLOGY AND HYGIENE, 355 trol of the will, and are transversely striated. The biceps is an example of a voluntary muscle. The involuntary muscles are those not under the control of the will, and are not transversely striated. The muscular coat of the arteries is an example. State the function of the hypoglossal or sublingual nerve. It is the motor nerve of the tongue and the mus- cles connected with the hyoid bone. What special centers exist in the medulla ob= longata ? Deglutition, salivation, mastication, vomiting, diabetic, cardio-inhibitory', cardio-accelerator, vaso- motor and respiratorion. What is the function of the cerebrum ? The cerebrum is the center of volition, perception and ideation. What is the difference between proteid and amy- loid food ? Proteids contain carbon, hydrogen, oxygen, nitro- gen and sometimes phosphorus. The amyloid foods contain carbon, hydrogen and oxygen ; the last two elements in the proportion to form water ; and in the molecule, six atoms of carbon or a multiple of six. The body can form amyloids from proteids, but cannot form proteids from amyloids. Describe the nerve fibre. 35 6 PHYSIOLOGY AND HYGIENE- A nerve fibre consists of an axis cylinder or nenroaxon covered with myelin or white substance of Schwann, which in tnrn is covered by the neurilemma or sheath of Schwann. Along the nerves there are constrictions known as the nodes of Ranvier. The nerves of the sympathetic system do not contain myelin, or are non-medullated. What is meant by flexion and extension of muscle? By flexion is meant the shortening or contraction of the muscle. The relaxation or lengthening of the muscle is called extension. Describe the form and give the location of the stomach. State the work accomplished by the stomach. The stomach is somewhat ovoid in form with its large end toward the left. It is situated in the front part of the upper abdomen in the epigastric region with its pyloric end a little below and to the right of the xiphoid cartilage, and its fundus projecting over into the left hypochondrium. The stomach changes the proteids into peptones, curdles milk, and liquefies fats. Describe the stomach and its movements during digestion. The stomach is an irregularly ovoid, muscular sack lined inside with mucous membrane, and outside with serous membrane. It is the dilated portion of gastrointestinal tract between the oesophagus and small intestine. The stomach holds, when full, about three pints. It has two openings, the cardiac, through PHYSIOLOGY AND HYGIENE. 35 y which the food enters the stomach, and the pyloric, through which the food leaves the stomach. It has two curvatures, the upper or lesser and the lower or greater. The portion of the greater curvature lying toward the spleen is called the fundus. When the food reaches the stomach the two ori- fices close tightly like sphincters ; the muscular wall also contracts down upon the food, and by means of the three muscular layers keeps the food in constant motion. Thus it brings fresh portions constantly to the surface to be acted upon by the gastric juice. A current passes down the fundus and greater curva- ture to the pylorus and back along the lesser curva- ture. After an hour of gastric digestion, the tightly closed pylorus gradually relaxes allowing some of the liquid chyme to enter the duodenum. Finally, at the end of three or four hours, even the more or less solid undigested portion is allowed to escape and enter the duodenum. Describe the alveolar process and state how it is developed. The alveolar process is made of an inner plate and an outer plate which are of compact osseous tis- sue. Between these plates there is a cancellous structureiwhich is hollowed out into compartments for the different teeth. The alveolar process is of mesoblastic origin be- ing formed by the osteoblasts of the periosteum. As the permanent teeth form, the process is somewhat rebuilt to accommodate them. 358 PHYSIOLOGY AND HYGIENE. What is the epiglottis ? The epiglottis is one of the single cartilages of the larynx. It is fonnd at the base of the ton gne and on the anterior edge of the upper opening of the larynx. State the distinction between mucous membrane and serous membrane. A mucous membrane consists of a layer or lay- ers of epithelial cells on a basement membrane and secretes mucus. A serous membrane consists of a single layer of endothelial cells on a layer of fibrous tissue. The mucous surfaces communicate with the ex- ternal surface. The serous cavities are closed sacs, and belong to the lymphatic system. Give the percentage of (a) animal matter in enamel ; give the percentage of (b) mineral matter in enamel. (a) Animal matter 3.5%. (b) Mineral matter 96.5%. Describe (a) the arterial system, (b) the capillary system. The arteries are tubes that carry the blood from the heart to the capillaries. The systemic arteries commence in the aorta which divides and sub-divides. The cross-section of the aorta is much less than the combined cross-section of the arterioles. The arteries have three coats. The intima consists of a layer of endothelial cells on a basement membrane, and num- erous yellow^ elastic fibres ; the media consists princi- PHYSIOL OGY AND HYGIENE. 359 pally of involuntary muscular fibres, arranged cir- cularly, which are controlled by the local vasomotor ganglia ; the adventitia consists principally of areolar tissue containing some elastic fibres. The yellow elastic fibres are comparatively more abundant in the large arteries; the muscular more abundant in the arterioles. The capillaries are small tubes consisting of a sin- gle layer of lance-shaped endothelial cells. They connect the smallest arteries with the smallest veins. They are about one-thirtieth of an inch long, and of sufficient calibre to allow a red corpuscle to pass through. How is bone nourished? How is dentin nourished ? Bone is nourished by the blood through the nutrient artery circulating in the marrow and Haver- sian Canals. It is also nourished by the perios- teum. The dentin is nourished by the dental pulp. State the function of epithelium. Epithelium secretes and protects. State the importance of the blood to the body. The blood carries the food and oxygen to the tissues, and carries the carbon-dioxide and other waste products from the tissues to the excretory organs. It is also by the circulation of the blood that the the temperature of the various parts of the body is equalized. j6o PHYSIO LOG Y AND HYGIENE, State the influence of posture on the action of the heart. There is an increase of nine to sixteen pulse beats when one rises from a reclining to a standing posture ; the volume and force of the pulse increases at the same time. The effect of the sitting posture is intermediate between the two. flention three inorganic substances found in the body. State in what part of the body each is found. Hydrochloric acid in the gastric juice. Sodium chloride in blood. Calcium carbonate in bone. How is animal heat regulated and maintained ? Animal heat is regulated by the thermotaxic centres which keep a proper balance between heat production and heat dissipation. It is maintained by katabolism, especially oxida- tion, in the tissues. What is the difference in function between the right and left sides of the heart ? The right side receives venous blood and forces it through the pulmonary circulation. The left side receives arterial blood and forces it through the systemic or greater circulation. State the hygienic precautions that should be taken to prevent the spread of typhoid germs. The drinking water should be boiled, and the milk also if it is suspected of possibly being in- fected. The feces and all secretions, like urine and PHYSIOLOGY AND HYGIENE. 3 6r nasal mucus should either be destroyed by fire or properly disinfected with a strong solution of bichlo- ride of mercury, chlorinated lime, formalin or car- bolic acid. The clothing of the patient and the bed linen should be placed in strong bichloride solution, or pre- ferably boiled for a half hour. The glasses and other dishes used by the patient should be boiled. What instruction as to hygiene and sanitation should be given in a case of diphtheria? The case should be isolated, the house quaran- tined, and possibly those who have been exposed (es- pecially children) had better be given a small dose of antidiphtheritic serum. The room should be well ventilated and as much sunshine as possible should be allowed to enter. The discharge from the mouth and nose should be destroyed by fire ; the dishes should be boiled. The clothing and bed linen should be boiled or destroyed by fire. After the case has terminated the room should be thoroughly disinfected with formalin or sulphurous acid, and the woodwork washed with i to 1,000 bichloride of mercury solution. Describe the physiological action of (a) saliva, (b) gastric juice, (c) pancreatic juice. The ptyalin of saliva converts starch into mal- tose. 362 PHYSIOLOGY AND HYGIENE. The rennen of gastric juice changes caseinogeii into casein, and pepsin in an acid medium converts proteids into peptones. As to pancreatic juice, trypsin in an alkaline so- lution converts proteids into peptones or even into lower bodies leucin, tyrosin and arginin. It also changes some of the albumoids into peptone-like bodies. Amylopsin com^erts starch into maltose. Steapsin splits up the fat into fatty acids and glycerin. The milk curdling ferment curdles milk. State the function of each of the following mus= cles : (a) temporal, (b) masseter, (c) occipito=frontalis, (d) orbicularis palpebrarum, (e) orbicularis oris. The temporal and masseter draw the lower jaw upward and are muscles of mastication. The occipito-frontalis moves the scalp and raises the eyebrows. It is a muscle of expression. The orbicularis palpebrarum is the sphincter mus- cle of the eyelid ; and is also used as a muscle of expression. The orbicularis oris is the sphincter of the mouth. It is a muscle of mastication, and also used in speak- ing and expression. State the normal pulse at each of the following ages : One year ; ten years ; fifty years. One \^ear it is 115 to 120. Ten years it is 80 to 90. Fifty years it is 70 to 75. Describe the capillaries. The capillaries are small tubes connecting the smallest arteries with the smallest veins. They con- PHYSIOLOGY AND HYGIENE. j6j sist of a single layer of lance-shaped endothelial cells. They are about one- thirtieth of an inch long, and on an average one-three-thousandth of- an inch in diameter. Why is blood light in the arteries and dark in the veins? Oxyhemoglobin found in the arteries is a lighter red than the deoxidized hemoglobin found in the veins. Is the natural condition of saliva alkaline or acid, and how is it tested ? It is alkaline, and is tested with litmus or phe- nol phthalein. What is the reaction of gastric juice ? Acid. What is the normal temperature of the surface of the body ? Very variable. The axillary temperature is about 98 degrees Fahr. Name some of the impurities found in rain water that is stored in cisterns. Unicellular organisms of many kinds, decaying vegetation, nitrites, ammonia, nitric acid, and mechan- ical impurities. What is bile ? What are its functions, and by what organ is it secreted ? Bile is the viscid bitter, greenish-brown or yellow, alkaline secretion of the liver, having a specific grav- ity of about 1020. There are about two pints secret- ed daily. 364 PHYSIO LOG Y AND HYGIENE. Bile neutralizes the acid chyme, precipitates the pepsin ; it emulsifies fats and aids in their absorption ; it increases peristalsis, and is an antiseptic ; it also contains waste products thrown off by the liver. Define assimilation. Assimilation means the conversion into proto- plasm of the nutrient material or food ingested. State the use and importance of (a) perspiration, (b) bathing. By the evaporation of perspiration the body is kept at a fixed temperature. The perspiration carries off waste products ; keeps the skin pliable, and when need exists relieves the kidneys of stress of work. Bathing cleanses the external surface, stimulates the function of the skin, and increases the general tone of the body. Define tissue. A tissue is a collection of intercellular substance and cells having the same anatomic and physiologic characteristics. State the object of respiration. By the act of respiration oxygen is taken into the blood, and carbon-dioxide, small quantities of ni- trogen, water and some organic volatile substances are thrown off from the body. In some animals the evaporation of water, and thus dissipation of heat by frequent respirations, is quite marked. Describe the movements of the heart. PHYSIOLOGY AND HYGIENE j6j The two auricles contracting force the blood through the auriculo-ventricular orifices into their cor- responding ventricles. These in turn contracting, force the blood past the semilunar valves into the pulmonary artery and aorta. The blood is prevented from regurgitating into the auricles during systole by the closure of the auriculo-ventricular valves. The ventricles then relax to be refilled with blood from the auricles. At the same time the semilunar valves are closed by the blood attempting to regurgitate from the arteries. During ventricular systole the heart becomes shorter and more globular, the base being forced down by the recoil from the forcing of the blood into the aorta. The heart rotates a little during systole. Give the mechanical uses of saliva. Saliva assists in deglutition, in mastication, in speaking and in taste. In what way does absorption of food occur ? Most of the food is absorbed by the villi in the small intestines. Two factors are concerned in absorption, — osmo- sis and vital activity of the columnar epithelium of the villi. The soluble salts, glucose, water and peptones are carried by the capillaries through the portal vein to the liver and from here into the general circulation. The fat is carried by the lacteals to the thoracic duct, and through it into the left subclavian vein. What is the function of the liver ? 366 PHYSIOLOGY AND HYGIENE. The liver secretes bile ; it forms glycogen, urea r uric acid and conjugate sulphate. Some of the red corpuscles are formed and others destroyed in the liver. The liver also destroys some poisons in the circulating blood. What are the functions of the muscles ? The muscles move the various parts of the body, and produce most of the heat necessary to keep the body at the normal temperature. Give the symptoms of insufficient oxygen in the blood. Dyspnoea, cyanosis, increase of blood pressure, and finally exhaustion with decrease of blood pressure, weak, flabby pulse, irregular, shallow breathing, con- vulsions and death. Describe the sympathetic nervous system, and state its functions. The sympathetic nervous system consists of a double chain of ganglia extending from the base of the skull to the coccyx along the anterior surface of the vertebral column. These ganglia are connected by intervening nerves. Besides this double chain of ganglia there are three large plexuses of fibres and ganglia (cardiac, solar and hypogastric) and numerous smaller plexuses. Proceding from the plexuses are numerous nonmedullated nerve fibres. The sympathetic system controls the movement of the abdominal viscera, and contains the vasomotor nerves and the cardioaccelerator. How should school seats be arranged with refer= ence to the windows ? PHYSIOLOGY AND HYGIENE* 3 6? The windows should be in back and to the left of the scholars ; on no account should they be placed in front. Describe the physiologic action of alcohol. Alcohol in small doses is a stimulant to the cere- brum, respiration, heart, and gastric mucous mem- brane. In large doses it is a depressant to cerebrum , respiration, heart, vasomotor system and gastric mu- cous membrane. It interferes with nutrition and causes a fall in temperature. Flention the valves of the heart and give their location. The mitral valve is located at the left auriculo- ventricular orifice. The tricuspid valve is located at the right auri- culo-ventricular orifice. The aortic semilunar valve is located between the left ventricle and aorta. The pulmonary semilunar valve is located be- tween the right ventricle and pulmonary artery. What is the composition of bone ? Bone is composed of 33% organic matter, chiefly collagen, and 67% inorganic matter, chiefly calcium phosphate and smaller quantities of calcium carbonate, calcium fluoride and magnesium phosphate. Name five of the principal elements of the body. Carbon, hydrogen, oxygen, nitrogen and sulphur. Define function. Function is the normal activity of an organ or group of organs. j 68 PHYSIOLOGY AND HYGIENE. State (a) the normal temperature of an adult ; the normal pulse of an adult. Normal temperature is 98.4 degrees Fahr. Normal male adult pulse is 72 per minute. State why blood does not coagulate within the blood vessels. The blood does not coagulate on account of its contact with the endothelium of the intima. Describe the origin and fate of the red corpuscles. In embryonic life the red corpuscles are first formed in the island Pander, later by the liver and spleen. After birth the red corpuscles are formed in the liver and spleen and the red marrow of bones, especially of the ribs. They are probably destroyed in the liver and spleen. How does the blood coagulate ? Fibrinogen, a proteid dissolved in the plasma, when acted upon by fibrin ferment in the presence of calcium salts is changed into fibrin.. The clot con- sists of this insoluble fibrin in the meshes of which are the corpuscles. The fibrin ferment is formed by the disintegration of the white corpuscles. Where and how is the blood changed from arterial to venous, from venous to arterial ? By the process of osmosis, the oxygen passes out through the capillary walls into the tissues and car- bon-dioxide passes into the capillaries ; thus it is changed from arterial to venous in the capillaries of the tissues. PHYSIOL OGY AND H YGIENE. 369 The venous blood is forced by the right ventricle into the pulmonary capillaries where the blood is sep- arated from the atmospheric air by only the capillary wall and the squamous epithelium of the air cells. There are three factors concerned in the ex- change of the respiratory gases or changing the venous blood into arterial blood. The first is the physiologi- cal law of pressure of gases ; the second chemical af- fiinity between hemoglobin and oxygen; and third, the selective vital activity of the epithelial cells of the air vesicles. Describe the red and white corpuscles, giving the characteristics of each. The red blood corpuscles are yellowish, bicon- cave, circular, non-nucleated, elastic discs about 1-3200 of an inch in diameter. After leaving the ves- sel they have a tendency to form in rouleaux or pile of coins. The red corpuscles are composed of a stroma in which is imbedded the hemoglobin, the oxygen car- rier of the blood. The white corpuscles when at rest are globular, granular, nucleated masses of protoplasm about 1-2500 of an inch in diameter and capable of amoe- boid movement. Some of them pass through the ca- pillary walls into the tissues and eat up bacteria ; these are called phagocytes. There are four principal varieties of leucocytes ; the lymphocyte, the large mononuclear transitional leucocyte, the polymorphonuclear leucocyte, and the 370 PHYSIOLOGY AND HYGIENE. eosenophile which contains coarse guanules readily stained with eosin. State the effects of starvation on the human body. The bodily weight gradually decreases and the temperature becomes subnormal. The fats are used up first, followed finally by the proteids, especially of the muscles. The amount of urea excreted is first, decreased ; but as the increased oxidation of proteids begins, the urea is increased. Finally death ensues from exhaustion. The heart and central nervous system lose but little in weight. Give the physiological properties and the chemi= cal composition of gastric juice. Gastric juice is a limpid acid liquid with a spe- cific gravity of about 1005. It is composed, of about 99.5% water and .5% solid. The bulk of which is made up of pepsin, rennin, and hydrochloric acid. Of the hydrochloric acid there are about two parts to the thousand. State the effects of battery currents on the normal human nerves. The faradic current stimulates them. A nerve during the passage of a constant cur- rent through it is said to be in a state of electrotonus. There is an increase of excitability at the negative pole or kathode, and decrease of excitability at the positive or anode. Differentiate between voluntary muscles and in= voluntary muscles. PHYSIOLOGY AND HYGIENE. 37 r Voluntary muscles are transversely striated, and are under the control of the will. Involuntary muscles are non-striated, not under the control of the will, and are much slower in action. How is the process of nutrition carried on ? The blood receives the digested and absorbed food and also the oxygen from the lungs. It carries these products to the tissues which take out what they need. The blood the receives the waste and carries it to the various excretory organs. The lym- phatics also carry some of the waste from the tissues and empty it into the venous blood. How does lime or other inorganic matter find its way into the blood ? Lime and other inorganic matter enter the body in the food and drinking water, and, being absorbed by the villi of the small intestines are carried by the portal vein to the liver and then into the general cir- culation. Describe the structure and give the functions of the veins. Tfae veins have three coats : The inner, com- posed of a layer of endothelial cells and elastic fibers; the middle, composed principally of involuntary muscular fibers, and the outer, composed of areolar tissue with numerous yellow elastic fibers. Many of the veins, especially of the extremities contain valves which help the movement of the blood in the veins. 372 PHYSIOLOGY AND HYGIENE. The veins carry the blood from the capillaries to the heart. They all contain venous blood except the pulmonary veins which contain arterial blood. State the functions of the nerves. The nerves conduct afferent impulses to the cen- tral nervous system and efferent impulses from the central nervous system. What are the general effects of breathing im= pure air? You get the symptoms of intoxication from the impurities of the air, such as headache, general ma- laise, loss of appetite, interference with mental activity, also interference with muscular activity, weak, low tension pulse.* State the characteristics of the parotid and sub= maxillary glands. The parotid secretion is thin, watery, poor in solids (.3% to .5%) contains no mucin, and has excel- lent penetrating powers. The submaxillary secretion on account of con- taining a quantity mucin is ropy, contains 2% to 2.5% solids, is of a greater specific gravity, and is excellent for aiding deglutition. The mixed saliva has a spe- cifiic gravity of about 1005, is alkaline, and contains especially ptyalin, potassium sulphoc3^ariide, mucin, sodium chloride and other salts. Of what two great groups of substances is the body composed ? Organic and inorganic. Mention the organs that compose the respiratory apparatus. PHYSIOLOGY AND HYGIENE. 373 The respiratory apparatus consists of the nose, pharynx, larynx, trachea, bronchi and air vesicles ; also of muscles moving the thorax, the diaphragm, the nerves (afferent and efferent) and the respiratory center in the medulla. What are the three kinds of digestion ? The three kinds of digestion are that of proteids, of carbo-hydrates and of fats. What are the direct sources of the heat of the body ? The most of the heat of the body is produced by katobolic changes, especially oxidation, taking place in the muscular and glandular tissues. Describe the parotid gland and give its function. Give location of the parotid gland. The parotid gland, the largest of the salivary glands, lies below and in front of the ear. The gland empties its secretion by Stenson's duct into the mouth through an opening in the mucous membrane oppos- ite the second upper molal tooth. It is a compound racemose gland composed of acini lined with polyhedral cells resting on abasement membrane. Under this is a close network of capillaries. The parotid secretes saliva. State the uses of perspiration. Perspiration is one of the excretions containing waste products and somewhat supplements the work of the kidney. By evaporation of perspiration the excess of heat produced in the body is dissipated. The perspiration keeps the skin moist. 374 PHYSIOLOGY AND HYGIENE. State the functions of dental pulp. The dental pulp nourishes the dentine. The odontoblasts which it contains form the dentine. The pulp contains nerves which give sensation to the tooth and thus protects it indirectly. How many pairs of cranial nerves are there ? What nerves supply the teeth ? There are twelve pairs of cranial nerves. The teeth are supplied by the superior and infer- ior maxillary divisions of the tri-facial nerve. On what particular phenomena does the study of Physiology depend ? Physiology is the study of the phenomena of living organisms. To what class of tissues do the teeth belong? The teeth belong to osseous tissue, and are formed from the mesoblast with the exception of the enamel which is formed from the epiblast. At what period of life is the development of teeth first indicated ? About the fortieth day of foetal life. Define calcification. By calcification we mean the deposition of calcium salts in a structure. How does alcohol affect digestion ? In small doses by its irritant action on the muc- ous membrane it causes an increase in secretion of gastric juice. Large doses retard digestion especially that of the stomach. PHYSIOLOG Y AND HYGIENE. 375 Define plethora anemia. In plethora there is an increase in the number of red corpuscles. In anemia there is a decrease of red corpuscles. In what organs is the blood changed ? It is changed in all the organs except the heart, but especially in the liver, kidneys, lungs, spleen, bone marrow and skin. What per cent of the weight of the body is water ? State the function of water in the body, and how it is eliminated from the body. About 75% of the body weight is water. In all the fluids of the body, water acts as a gen- eral solvent, beiug necessary to secretion and the carrying of nutrition to and the waste products from the tissues. By its evaporation it dissipates large quantities of animal heat. It is eliminated from the body by the kidneys, sweat glands, lungs and in feces. Describe the structure of the teeth. The tooth is made up of a central pulp cavity containing connective tissue, blood vessels, nerves, and around these a layer of odontoblasts which form the dentine and send protoplasmic prolongations into the dentine tubules. Around the pulp cavity is this covering of dentine which in chemical composition resembles bone but contains a little more inorganic material. Below the neck of the tooth the dentine is surrounded with the crusta petrosa which is formed by the osteoblasts of the dental periosteum. $76 PHYSIOLOGY AND HYGIENE. Microscopically it resembles bone with the ab- sence of the Haversian canals. Above the neck of the tooth, the dentine is covered with enamel which is formed by the ameloblasts derived from the epi- thelium of the mouth. The enamel consists of hexagonal columns set on end radiating from the center of the tooth. The en- amel contains very little organic matter, about 3.5%. What set of muscles gives the horizontal motion to the inferior maxillary ? Internal and external pterygoids. Define afferent and efferent nerves. Afferent nerves carry impulses from the peri- phery to the central nervous system. Efferent nerves carry impulses from the central nervous system to the periphery. Name three kinds of food from which starch is de- rived, and give the percentage of starch in each. Potatoes 23.7%. Wheat 70%. Rice 84.5%. What is the function of the gustatory nerve ? The gustatory nerve is the nerve of taste. What is casein, and where is it found ? Casein is a coagulated proteid found in curdled milk and cheese. How are bone and dentine formed ? Bone is formed by the osteoblasts of the peri- osteum. PHYSIOLOGY AND HYGIENE, 377 : Dentin is formed by the odontoblasts. The ex- ternal layers of cells of the pulp cavity. What is the function of the dental periosteum ? The dental periosteum forms and afterwards nourishes the crusta petrosa, and holds the tooth in the alveolar process. How does the blood circulate through the heart ? The blood passes from the superior and inferior vena cava into the right auricle, which contracting, forces it through the tricuspid valve into the right ventricle. The right ventricle then contracts and forces the blood past the pulmonary semilunar valve into the pulmonary artery. This artery carries the blood to the lungs, and from these it is carried back through the pulmonary veins into the left auricle. Then it passes through the mitral valve into the left ventricle, which, contracting, forces the blood into the aorta. What is the function of the nervous system ? The function of the nervous system is to carry afferent impulses from the periphery and as a result of such impression to send out efferent impulses, to receive impressions, to preside over thought, and to control the action of the various parts of the body. Give the functions of connective tissue. The connective tissue binds, protects, supports and connects the softer and more vital tissues. Give the size and function of the red corpuscles. The red corpuscles are 1-3200 of an inch in diameter and 1-12000 of an inch in thickness. They j?8 PHYSIOLOGY AND HYGIENE. carry the oxygen to the tissues from the lungs and possibly a little carbon-dioxide back to the lungs from the tissue. How may coagulation be hastened ? It may be hastened by increasing the tempera- ture, injury to the vessel walls, contact with foreign matter and oxygen, agitation and addition of calcium salts. State how many of the seventy known elements form a practical part in making up the animal tissue, and mention the four most important of these elements. There are sixteen to nineteen elements found in the tissues of the body. Of these the most import- ant are carbon, oxygen, hydrogen and nitrogen. Name the four groups of tissues of which the organs of an adult are composed. Epithelium, connective, nervous and muscular. What is food ? State why milk is so nearly a perfect food. Food is that which taken into the body nourishes the tissues or supplies heat. Milk is so nearly a perfect food because it con- tains all the chemical compounds necessary to life, that is, proteids, carbohydrates, fats, salts and water. What are proximate principles ? Proximate principles are substances that enter in- to the composition of the body. Name three of the most important inorganic prox= imate principles, and state where they are found in the body. PHYSIOLOGY AND HYGIENE. 3 y 9 Calcium phosphate is found in bone. Sodium chloride is found in the blood. Water is found all through the body. Are inorganic ingredients of food necessary to sus= tain life ? Why ? They are necessary because they are indispensa- ble constituents of the structure of the body, — as cal- cium salts in bone ; because the alkaline bases are necessary to neutralize the acids formed by the pro- teid metabolism ; because they are necessary for di- gestion and absorption, and because water is the gen- eral solvent of the body. Describe the lymphatic system and give its func= tion. The lymphatic system consists of numerous thin walled vessels lined with endothelium, of lymphatic glands situated on these vessels, of the thoracic duct, of the lymphatics of the intestines called lacteals, and the spleen. The thoracic duct begins in a dilated extremity called the cisterna magna about the level of the second lumbar vertebra, and runs up along the vertebral col- umn emptying into the left subclavian vein. It re- ceives the lymph from the lower extremities, abdomen, left lung, left arm and left face. The lymph of the right lung, right arm and right face is emptied through a small vessel into the right subclavian vein. The lymphatic glands are found along the course of the lymphatic vessels,and are composed of lymphoid tissue in the center of which are cells rapidly under- going karyokinesis. The lacteals are the lymphatic j8o PHYSIOL OGY AND HYGIENE. vessels of the intestines and carry the absorbed fats from the villi to the thoracic duct. The lymphatic S3^stem carries back into the blood circulation the blood plasma that has osmosed through the capillary walls into the tissues. It also forms leucocytes and carries the absorbed fat from the intestines into the general circulation. The secretion of some of the ductless glands passes through the lym- phatics into the blood channels. Describe the circulatory apparatus. The circulatory apparatus consists of the heart, arteries, capillaries and veins. The heart is a hollow,muscular organ, lined inside with the endocardium and outside with the pericardi- um. It is pyramidal in shape about 5^ inches long, 3^/2 inches wide and weighs about ten ounces. It is divided into four cavities, two auricles and two ven- tricles. The ventricles are the most^important cavities, the left ventricle being three times as thick as the right ventricle. The ' arteries are the vessels that carry the blood from the heart to the capillaries. They all contain arterial blood with the exception of the pulmonary artery. Histologically they consist of three coats. The intima or internal coat is composed of yellow elastic fibers lined internally with a layer of endothe- lium ; the media or middle coat is made up mostly of involuntary muscular fibers running transversely to the long axis of the artery ; the adventitia or external coat is composed of areolar tissue containing numerous yellow elastic fibers. The vaso-motor nerves end in PHYSIOL OGY AND HYGIENE. 3 8i the ganglia in the muscular coat. The elastic fibers are found comparatively more numerous in the larger arteries, and the muscular fibers in the arterioles. The capillaries are the small blood vessels con- necting the smallest arteries with the smallest veins, and consist of a single layer of lance shaped endothe- lial cells. The capillaries on an average are 3 o of an inch long and 1-3000 of an inch in diameter. The veins are similar in structure to the arteries but the coats are not so thick. Some of the veins, especially those of the extremities have valves which prevent the regurgitation of bloodj during muscular contraction. What is the function of the red blood corpuscle ? Has it a nucleus ? The red corpuscles are not nucleated. They carry oxygen from the lungs to the tissues and possib- ly a little carbon-dioxide back to the lungs What is pepsin ? Where is it found ? Pepsin is a ferment that in an acid medium changes proteids into peptones. It is found in the gastric juice. What disposition is made of gastric juice after serving its purpose in aiding digestion ? The hydrochloric acid is neutralized by the al- kaline bile and the pepsin is precipitated. Define endosmosis, exosmosis. Endosmosis is the passage of a liquid through a porous diaphragm from without inward. Exosmosis is the passage of a liquid through a porous diaphragm from within outward. SPECIAL DENTAL ANATOMY AND PHYSIOLOGY. Give the most prominent differences between the form of the upper and lower bicuspids and some of the reasons therefor. The inferior bicuspids are somewhat smaller in every respect ; the crowns are much more rounded, cusps not so strongly developed ; buccal and lingual cusps are unlike superior bicuspids, being connected by a transverse ridge ; the roots are more flattened from mesial to distal and seldom, if ever, bifurcated. The upper bicuspids show a greater tendency to bifurca- tion. Name the muscles which effect the various move= ments of the lower jaw. Temporal, masseter, internal and external ptery- goid, genio-hyoid, mylo-hyoid, platysma-myoides,and the digastric. How is secondary dentine formed ? By the odontoblasts, being stimulated into ac- tivity by irritation of the pulp. It is most frequently caused by the advance of caries. How is cellular activity stimulated in the resorp= lion of the roots of deciduous teeth ? By the vascular papilla and probably by the pressure caused by the advance of the permanent teeth. ANA TOMY AND PHYSIOLOG Y 3 8j Give the foramen of exit, principal branches of distribution and function of the hypoglossal nerve. Anterior condyloid foramen ; branches of distri- bution are : Meningeal descendens hypoglossi, thyro- hyoid and muscular. It is the motor nerve of the tongue. Give the functions of that part of the facial nerve which is distributed to the oral cavity. Influences the sense of taste, deglutition, move- ments of the uvula, and soft palate and the secretion of the submaxillary and parotid glands. How, and from what source does a tooth receive its blood supply ? By means of the pulp and pericemental mem- brane ; from the inferior dental to the inferior teeth, and from the alveolar and infra-orbital to the upper teeth. What is the function of the fifth pair of nerves ? Gives sensibility to all parts of the face to which it is distributed, is the motor nerve of the muscles of mastication, and through fibers from the sympathetic governs the nutrition of the special senses. What anatomical structures are engaged when the food passes from the mouth to the stomach ? The tongue, soft palate, constrictors of the pharynx, uvula, pharynx and esophagus. What noticeable change would appear if the sev- enth nerve were excised ? * Complete loss of motion of the muscles of expres- sion of the face. 384 ANATOMY AND PHYSIOLOGY. Mention the difference between parotid and sub= lingual saliva. The parotid saliva is thin and watery, while the sublingual is thick and viscid, as it contains much mucin. More ptyalin is found 'in parotid saliva than in sublingual saliva. Describe the natural means by which the de= ciduous teeth are shed. The resorption begins at the apical extremities of the root and gradually progresses towards the crown. It is brought about by the agency of the osteoclasts ; resorption taking place in the order of eruption contained in vascular papillae. What muscles are most active in opening the mouth ? Digastric, genio-hyoid, mylo-hyoid and platysma- myoides. Give in the regular order the normal average age at which the deciduous teeth are erupted. C. I. 5th to 7th month L. I. 9th " nth 1st M. 1 2th " 14th Cuspids, 14th " 1 8th 2nd M. 1 8th " 25th Describe how salivary calculus is deposited. Where most abundant and why ? Deposited upon the surfaces of the teeth from the saliva ; most abundant at the necks of the inferior anterior teeth because there is less friction, and the submaxillary and sublingual glands open near them. a ANATOMY AND THYSIOLOGY. jXj Name the muscles concerned in the act of de= glutition. Extrinsic and intrinsic muscles of the tongue, tensor palati, azygos uvuli, palato-pharyngeus, su- perior constrictor of pharynx, middle and inferior constrictor of pharynx, also the muscular coat of the esophagus. What are the fluids of the mouth ? Give their active principle and function ? Saliva from the salivary glands, and mucus from the mucous glands. The active principle of saliva is ptyalin, that of mucus is mucin. The function of saliva is to soften and moisten the food and to con- vert starch into maltose. The function of the mucus is to keep the mucous membrane of the mouth moist. Give the period of eruption of the permanent teeth. 1st M. 6th to 7th year. C. I. 7th " 9th " L. I. 8th " 10th " 1st B. C. 10th " nth " 2nd B. C. nth " 12th " Cuspids, 1 2th " 13th " 2nd M. 1 2th " 13th " 3rd M. 1 6th " 25th " What is the function of the peridental membrane and how dees it receive its blood supply ? The function of the peridental membrane is to hold tooth in socket, give sense of touch to tooth, act as cushion to receive shock due to mastication, 386 ANATOMY AND PHYSIOLOGY. to nourish tooth when pulp is devitalized, and to nourish cementuni of tooth. It receives its blood supply from the same arterial branch as the tooth, this branch giving off several twigs before entering the apical foramen. Describe the changes which occur in the tis= sues in the movement of the teeth in orthodontia. There is first a compression of the peridental membrane and pressure on the alveolar wall in the direction of the applied force, and a distention of the peridental membrane in the opposite direction, the hard structure in front is then acted upon by the osteoclasts and the bone behind is built up by the osteoblasts. When a tooth is rotated in its socket, the fibers of the peridental membrane are stretched. Describe the third division of the fifth nerve, and tell how it differs from the second division. The larger or sensory root of this compound nerve arises from the inferior angle of the Gasserian ganglion and passes downward through the foramen ovale in the sphenoid bone, when the motor branch unites with it forming one nerve. It then descends vertically and divides into the anterior, middle and posterior branches. The anterior branches divide in- to the buccal, deep temporal, masseteric, and ptery- goid branches ; the middle divides into the lingual, and inferior dental ; the posterior branch divides into the auriculo-temporal branches. It differs from the second division in having a motor root. ANA TOMY AND PHYSIOLOG Y. 387 Describe the second division of the fifth nerve. The second division of the fifth nerve is a sensory nerve. It commences at the middle of the Gasserian ganglion and passes forward through the foramen rotundum, before going through this foramen it gives off a recurrent meningeal branch. It then crosses the spheno-maxillary fossa, enters the orbit through the spheno-maxillary fissure, traverses the infra-orbital canal, and appears upon the face at the infra-orbital foramen. In the spheno-maxillary fossa it gives off the spheno-palatine, temporo-malar and posterior superior dental. In the infra-orbital canal it gives off the anterior and posterior superior dental, on the face it gives off the labial, nasal and palpebral branches. Describe the physiological action of the saliva in digestion. The action of the saliva in the process of digest- ion is to soften and moisten the food and convert starch into maltose, by the agency of the organic fer- ment, ptyalin. Describe the process of absorption of the roots of the teeth and trace the absorbed material to its terminal. The absorption of the roots begins at the apical end and gradually progresses towards the crown. Commencing about the 4th year in the central incisor, decalcification takes place in the teeth in the order of their eruption. This phenomenon is due to the action of the ce- mentoclasts and odontoclasts. The decalcified mater- ial is absorbed by the vascular papilla, transferred by j88 ANATOMY AND PHYSIOLOGY. this means into the general circulation, carried to the various excretory organs and eliminated from the body. Describe the dental tubuli. The dental tubuli are small wave-like canals which run from the periphery of the pulp in a perpen- dicular direction to the surface. They vary in size from i.i to 2.3 microns. They anastomose freely. Describe the process of the development of the inferior maxilla, from which layer, and what tissue. Development takes place from six centres for each lateral half, the nuclei being deposited as early as the sixth or eighth week. The mandibular plates which are thrown off from the sides of the cranial base unite at the median line, after this period Meckel's car- tilage is developed in the substance of the mandibular plates and it is about this band that ossification takes place. The inferior maxilla is derived from connec- tive tissue of the mesoblastic layer of the blasto- derm. What differences are there between the roots of the deciduous and permanent molars, and some of the reasons ? The roots of the deciduous molars are the same in number as the roots of the permanent molars, but they are more widely separated at their apical ex- tremities and are smaller than the roots of the per- manent molars. At what age are the roots of the six anterior teeth fully developed ? ANA TO MY AND PHYSIOL OGY. 3 8 9 The permanent incisors are developed at the age of eleven years, the cuspids at thirteen years. The deciduous C. I. at eighteen months after birth and L. I. at sixteen months, and the cuspid two years after birth. In what abnormal condition will resorption of the roots of temporary teeth cease ? When the pulp of the deciduous tooth dies. Describe an odontoblast and give its function. They are large elongated, multipolar, nucleated cells. Before dentiniiication they are spheroid. Dur- ing this process their extremities become somewhat flattened and square, and in the old they again assume their spherical form. The function is to build up the dentine. What tissue is developed from the outer layer of cells, and what of the inner layer of the follicular sac? From the outer the peridental membrane is de- veloped and from the inner la}^er the cementum is developed. From what sources do the different structures of a tooth receive their nourishment? The enameljfrom the dentine. Dentine, through the pulp. Pulp, from its vascular supply. Cement- um, from the peridental membrane. What great muscle lifts the lower jaw ? De= scribe its origin and insertion, and to what order of levers does it convert the lower jaw? The temporal muscle. It arises from the temporal fossa and fascia, and is inserted into the coronoid pro- 39 o ANA TOMY AND PHYSIOLOG Y. cess of the inferior maxillary at its inner surface, apex and anterior border. It converts the lower jaw into a lever of the second order. In how many and what bones are the teeth located ? The teeth are located in three bones, two superior maxillary bones and the inferior maxilla. Describe the manner of their attachment. They are placed in the alveolar sockets of the up- per and lower jaw, and held in place by the transverse fibres of the peridental membrane and the dental lig- aments ; the articulation being known as a gomphosis. Give the forms and location of the several classes of the human teeth and the functional reasons therefor. The human teeth are divided into two classes, the simple and complex. In the simple class, the modi- fied cone is the predominating form, the free extrem- ity of the crown forming the base of the cone ; this class of teeth is found in the anterior part of the sup- erior and inferior maxillary bones and are so formed in order to best perform their function of grasping, in- cising and tearing. The complex teeth are composed externally of a number of cones all uniting at a com- mon base, — the neck. The roots are formed of sim- ple cones while the crowns are formed of smaller modi- fied cones; these teeth are placed posterior to the simple class, and are so formed and placed in order to best perform their function of grinding and crushing. Describe the maxillary sinus. The maxillary sinus is a pyramidal shaped ANATOMY AND PHYSIOLOGY. 39 i cavity, situated within the superior maxillary bone, its apex is directed outward and is formed by the malar process, the base by the outer wall of the nose, the roof by the orbital plate and the floor by the alveo- lar process. The walls of the sinus are very thin and lined with mucous membrane. The sinus communi- cates with the middle meatus of the nose. Describe the aveolus. An alveolus or tooth socket is formed by the outer and inner plate of the alveolar process. The shape and depth is regulated by the forms and length and number of the roots of the tooth which it sup- ports. What are the interproximal spaces and by what are they normally occupied ? The interproximal spaces are V shaped spaces between the points of contact and the cervical line ; they are normally occupied by gum tissue. Describe the different tissues of the teeth and give their location. Enamel, dentine, cementum and pulp. The en- amel covers the crown of the tooth, dentine forms the body of the tooth and is intermediate in position be- tween the enamel and pulp ; the pulp occupies the central chamber of the tooth and the cementum covers the roots of teeth. Trace nerve supply of the lower teeth. The lower teeth are supplied by small twigs given off by the inferior dental nerve as it passes through the inferior dental canal. The inferior dental is a 392 ANATOMY AND PHYSIOLOGY. branch given off by the third division of the fifth } after it passes through the foramen ovale. Describe the root of a superior central incisor. The root of this tooth is conical in form, its base is directed downward,,, the apex upward. It has three surfaces, mesial, distal and labial. The labial side is the most flattened, while the two remaining sides are of equal length and oval in form. What do you understand by the horns of the pulp and why is a knowledge of their existence important ? The horns of the pulp aie prolongations of pulp which penetrate the various lobes of the tooth. A knowledge of their existence is necessary in order to prevent injury to pulp in operations on the teeth. How do the arterial vessels in the pulp differ from those just outside of the apical foramen ? The arterial vessels in the pulp are found as a capillary network, composed of a layer of endothelial cells while those outside of the foramen are much larger consisting of two coats. What various tissues and forces hold the tooth in the superior maxilla ? They are firmly imbedded in the alveolar socket. There is a special development of bone closely moulded to the roots of the teeth. Between the roots of the teeth and the walls of the alveoli is the peri- dental membrane which is attached to root and alveoli. This is one of the agents which hold the tooth in place. ANATOMY AND PHYSIOLOGY. 393 Describe the occlusal surface of a superior second bicuspid and the manner of formation of the sulci. The occlusal surface presents a central groove, two triangular grooves, mesial marginal ridge. Buc- cal grooves are shallow. The sulci are formed by the union of the cuspid. Describe the crown of a superior central incisor in its form and tissues. The crown of a superior central incisor is wedge shape, labial surface convex, palatal surface concave, composed externally of enamel under which is the body of the crown which is composed of dentine. This encloses the pulp. What variation occurs in a pulp chamber of a su- perior central incisor ? During the early life of the tooth, the margins of the chamber nearest the cutting edge, presents three well defined lobes. These disappear as the tooth grows older, and are seldom found after the 15th year. At the time of eruption the pulp cham- bers form almost a perfect cone. At the tenth year the apical foramen is established. What is the difference between a sulcus and a fis= sure ? A sulcus is a short and shallow groove while a fissure is longer and deeper. What are the labial lobes of superior central incisor? The labial lobes are the three parts of the labial 394- ANATOMY AND PHYSIOLOGY. surface marked off by the developmental grooves. They originate one from each centre of calcification. Describe the bone of the aveolar process ; how does it differ from the upper and lower dentures ? The alveolar process of the superior maxilla is formed on the lower edge of the external surface. It is broader behind than in front, and is divided into sockets for the reception of the teeth. The sockets are divided into compartments for the reception of the roots. The differences between the upper and lower processes are, first, the sockets are smaller ( in the lower, and the sockets of the molars have two compartments while the upper have three. Describe the variations in the lingual surface of a superior lateral incisor. It is subject to much variatiou and form, the palatal fossa may be present as a smooth unbroken con- cavity, or may be sub-divided by a longitudinal ridge. The marginal ridges are usually well pronounced, but the surfaces may in some cases be smooth and flat with absence of ridge and fossa. What cranial nerves supply the superficial muscles of the face with motion ? The seventh pair or facial nerves. To what class do the nerves which supply the teeth belong ? Describe their function. To the class of sensory nerves. They carry sen- sations to the brain. Describe the difference of the cusps of the superior and inferior first molars. ANATOMY AND PHYSIOLOGY. 395 The cusps of an inferior first molar are not so well defined as that of the superior,and in the inferior there are always five in number, while those in the super- ior have four cusps, but may have five cusps. With what is the surface of the gum covered ? Mucous membrane. Describe anatomically a vital cuspid tooth. The tooth is divided into crown, neck and root. The crown presents four surfaces, labial, palatal, mes- ial, and distal, two margins cervical and cutting edges and the mesial distal angle. The cusp divides the cutting edge into mesial and distal cutting edges, the neck makes a decided construction between the crown and root on labial and palatal sides. The root is the largest and longest of all of the teeth. It is cone shaped and rounded on labial and palatal surfaces. Describe the occlusal surface of a superior first molar. It presents a mesio-buccal cusp, disto-buccal cusp, mesio- and disto-palatal cusp, a buccal groove, oblique ridge, a fifth cusp at times, distal marginal ridge and a disto-palatal groove. Describe the temporo=maxillary articulation. What movements take place ? What muscles produce them ? It is a double arthrodial joint, the parts entering into its formation being the anterior part of the glenoid cavity, the eminentia articularis, the condyle of the lower jaw, also the internal and external lateral J 9 6 ANA TO MY AND PHYSIOLOG Y. ligaments, the stylo-maxillary ligament, an inter-artic- nlar iibro-cartilage and two synovial membranes. The jaw is depressed by the contraction of the digastric, geniohyoid, mylo-hyoid, and platysma my- oides ; elevated by the temporal, masseter and internal pterygoid muscles ; moved laterally by the alternate contraction of the external pterygoid muscles ; moved anteriorly by the pterygoid and posteriorly by the genio-hyoid, mylo-hyoid, and posterior fibers of the temporal muscles. LIBRARY OF CONGRESS OOOEbDbfi?^