Torus palatinus
Department of Diagnostic
Radiology, Nelson R Mandela School of Medicine, University of
KwaZulu-Natal and King Edward VIII Hospital, Durban, South
Africa
Kupffer and Bessel-Hagen coined the term torus palatinus in
1879 for a benign osseous protuberance arising from the midline
of the hard palate. Tori are present in approximately 20% of the
population and are occult until adulthood. Recent advances in
modern radiology have led to improved evaluation and diagnosis
of tori.
S Afr J Rad 2013;17(4):141-142.
DOI:10.7196/SAJR.876
A 54-year-old woman presented with a firm, painful swelling of
the hard palate of 4 years’ duration. A clinical diagnosis of
maxillary torus without ulceration was made. Computed tomography
(CT) was performed for confirmation of torus palatinus and to
aid surgical planning. The CT scan demonstrated lobulated bony
outgrowths arising from the inferior margin of the hard palate,
consistent with torus palatinus. (Fig. 1).
Discussion
Torus palatinus is a benign, reactive hyperplasia of osseous tissue extending outward from the surface of the bone.1 It is an intra-oral osseous protruberance of varying size arising along the midline suture of the hard palate.2 Jainkittivong and Langlais3 characterised these developmental anomalies as sessile nodular bony masses comprising hyperplastic mature and trabecular bone. The torus can arise from the inner or outer surface of the maxillary bone, and is generally named according to location.1 , 4 Torus palatinus presents in approximately 20% of the population and is occult until adulthood.1 , 5 The term was coined by Kupffer and Bessel-Hagen in 1879, many years after its first observation.2
The aetiology of torus palatinus has been researched extensively and is thought to arise from an interplay between genetic and environmental factors and masticatory function. The quasi-continuous genetic or threshold model states that the environmental factors responsible must first reach a threshold level before genetic factors can express themselves in the individual. There is a prevalence in middle-aged females, with racial and ethnic group differences.2 , 3
The other most common intra-oral exostosis − torus mandibularis − is a bony outgrowth on the lingual surface of the mandible, most frequently in the premolar or canine area. The concurrence of the different forms of tori shows a low prevalence.2 , 3
Tori are usually asymptomatic except when complicated by trauma or ulceration. They may also interfere with speech, mastication or fabrication of maxillary dentures.1 , 5
On panoramic radiographs, small tori palatini are not well demonstrated owing to overlying bony structures; larger tori can be easily detected with a bosselated or multi-lobulated appearance.1 , 5] With advances in imaging techniques, multidetector CT including multiplanar imaging, 3D reconstructions and volume rendering techniques, these osseous protuberances of varying size and locations can be diagnosed to facilitate surgical planning.1
When treatment is elected, the lesions may be chiselled
off the cortex or removed via a burr, cutting through the base
of the lesion. Recurrent lesions may occur, but there is no
malignant potential. Gardner syndrome should be excluded if
patients present with multiple exostoses that are not in the
classic torus locations. Intestinal polyposis, desmoids and
cutaneous fibromas are other common features of this autosomal
dominant syndrome.5
Fig. 2. Reconstructed sagittal CT image shows lobulated outgrowths from the hard palate.
Conclusion
This report highlights a case of torus palatinus − a
benign bony exostosis arising from the midline of the hard
palate. Tori have been well documented and researched for some
centuries, they occur currently, and are clinically and
radiologically diagnosed and managed.
1. DelBalso AM. Lesions of the jaw. Semin Ultrasound CT, MR 1995;16(6):487-512. [http://dx.doi.org/10.1016/S0887-2171(06)80022-3]
2. Antoniades DZ, Belazi M, Papanayiotou P. Concurrence of torus palatinus with palatal and buccal exostoses. Oral Surg Oral Med Oral Path Oral Radiol Endod 1998;85:552-557. [http://dx.doi.org/10.1016/S1079-2104(98)90290-6]
3. Jainkittivong A, Langlais RP. Buccal and palatal exostoses: Prevalence and concurrence with tori. Oral Surg Oral Med Oral Path Oral Radiol Endod 2000;90:48-53. [http://dx.doi.org/10.1067/moe.2000.105905]
4. Yonetsu K, Nakamura T. CT of calcifying jaw bone diseases. AJR 2001;177(4):937-943. [http://dx.doi.org/10.2214/ajr.177.4.1770937]
5. Bouquot JE, Muller S, Hiromasa N. Lesions of the oral cavity. In: Gnepp D. Diagnostic Surgical Pathology of the Head and Neck. 2nd ed. Amsterdam: Saunders, 2009:191-308.