SURGICAL REMOVAL OF MANDIBULAR TORI & ITS USE AS AN AUTOGENOUS GRAFT

Summary

While there is a hereditary component to tori, this does not explain all cases. Tori tend to appear more frequently during middle age of life. Certain ethnic groups are more prone to one torus or the other. The torus is mainly removed due to prostodontic reasons, as it may also be used as biomaterial, not only in periodontology, but also in implantology.1 This case report deals with the surgical removal of tori mandibularis thereby improving clinical implications2 and serving as an adequate autogenous bone graft.

Background

The tori (meaning “to stand out” or “lump” in Latin)2 are exostosis that are formed by a dense cortical and limited amount of bone marrow, and they are covered with a thin and poorly vascularized mucosa. They are usually located at the longitudinal ridge of the half palatine, on the union of the palatine apophysis of the maxillae or on the internal side of the horizontal branch of the jaw, above the mylohyoid line and at the level of the premolar area and canine area, presenting a very slow and progressive growth that can stop spontaneously.3,4,5,6 There are many notions on the formation and implications of tori (Drennan, 1937; Singh, 2010; Cantín et al., 2011),7,8,9 but these remain largely unsubstantiated to date. For example, according to Eggen and Natvig (1986),10 the number of functional teeth seems to be important for the maintenance of tori. This view lends credence to the concept that (abnormal) mechanical loading presumably is associated with the formation of tori.11 However, tori can also be considered as a potential donor site for autogenous harvesting of bone in the mandibular region. The cortical and cancellous nature of the bone, with a thickened outer cortical plate of haversian bone, makes it an excellent choice as a donor site for grafting procedures.

History

A 47 year old male presented in the dental department with the chief complaint of bleeding from gums since 1½ year and pathological drifting of teeth since 8 months. Intra- oral examination revealed that the gingiva was bluish red in color, swollen and bleeds on probing with generalized grade I and grade II mobility of teeth, pocket formation & existing bilateral mandibular tori (Fig.1). There were missing 35,36 for which the patient wanted removal prosthesis. The exostois extended bilaterally from canine till second premolar on both the sides. The swelling 

was covered with thin, intact mucosa with normal color. It was non- tender and hard in consistency on palpation.

Treatment

A full mucoperiosteal flap was raised under local anesthesia from lower left side canine till second molar and the exostosis was surgically removed with chisel and mallet and the flap was sutured. (Fig. 2) Patient was recalled after 1 week for suture removal.(Fig. 3) Second surgery was performed on the right side and the full thickness flap was raised under local anesthesia extending from canine till second premolar of right side. The flap was raised on the buccal side as well as there was bone loss evident on radiograph. (Fig.4. Fig. 5, fig. 6, fig. 7) Lingually, flap was raised and extended up to the exostosis. (Fig. 8) Exostosis was removed with the surgical chisel and bone mallet (Fig. 9, Fig. 10). Autogenous bone graft was placed at the required site and sutures were placed (Fig. 11, fig. 12). Coe- pak was placed( fig. 13). Patient was recalled after 10 days. (Fig. 14)

Outcome & Follow- up

The patient returned 10 days after surgery for suture removal and to check healing. Coe-pak was removed followed with sutures. There was minimal inflammation, and the patient indicated that he had minimal discomfort after surgery and that the area felt normal 3 days after surgery A follow-up appointment was scheduled at 4 weeks after surgery to check the site. The surgical site 4 weeks after surgery shows lack of inflammation and complete healing.

Discussion

The cause of mandibular torus has not been clearly determined, though both genetic factors and environmental factors such as diet, presence of teeth, and occlusal pressure are suspected to be involved [1]. Some reports have suggested that genetic predisposition to mandibular torus may be inherited in a dominant manner. In regard to environmental factors, one study suggested a correlation between the number of existing teeth and incidence of mandibular torus, as the number of existing teeth was significantly higher in patients with mandibular torus than in those without mandibular torus. Further, occlusal stress such as bruxism and teeth clenching have been noted to be involved in the development of the condition. The risk of mandibular torus generally decreases after middle age. In the present case, genetic factors and diet of the patient were unknown. Despite his advanced age, the patient had 28 existing teeth and demonstrated a favorable occlusal relation. Environmental factors, such as long periods of good occlusion with many remaining teeth, seem to be largely responsible for both the occurrence of and an increase in mandibular torus. Generally, surgical resection is not required for mandibular torus, as long as the condition remains asymptomatic. However, treatment is indicated when subjective symptoms such as discomfort, pain, articulation disorder, or problems in the insertion of dentures are present. In the present case surgical resection of tori was required to serve as adequate bone graft in areas with periodontal bone loss evident on radiographic examination and also for placement of removable prosthesis.

Learning Points

The technique has been described that offers substantial benefits for the clinician and the patient. Use of the mandibular tori as local donor sites for autogenous graft placements reduces morbidity associated with other graft procedures, enhances site preparation, and aids the prosthetic phase. Despite these clinical advantages, the applicability of the technique is limited to the small segment of the patient population that exhibits mandibular tori.

Conclusion

Exostosis is a common occurrence as sited in the literature. These slow-growing, dense cortical bone deposits are not usually an issue with patients, except when removable prosthetics must sit either adjacent to or over these areas. Because the overlying tissue is thin, pressure or food abrasion may cause ulceration. Excision of exostosis in the mandible is a safe, predictable procedure with minimal postoperative sequel.

References

1. Castro Reino O, Perez Galera J, Perez Cosio Martin J, Urbon Caballero J. Surgical techniques for the exeresis of torus, both palatal and mandibular. We observe indications, contraindications and complications as well as enumerate all the right events to realize correctly the said techniques. [Surgery of palatal and mandibular torus]. Rev Actual Odontoestomatol Esp. 1990;50:47-50, 53-6.

2. Lindhe, J., Lang, N.P& Karring, T- Clinical Periodontology and Implant Dentistry, Blackwell Munksgaard, Blackwell Publishing Ltd., 9600, Garsington Road,Oxford OX42DQ, U.K. Lang, N.P., Mombelli, A.& Attstom, R. Oral Biofilms and Calculus; 5th ed. 2008: 183-206.

3. Jainkittivong A, Langlais RP. Buccal and palatal exostoses: prevalence and concurrence with tori. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2000;90:48-53.

4. Bruce I, Ndanu TA, Addo ME. Epidemiological aspects of oral tori in a Ghanaian community. Int Dent J. 2004;54:78-82.

5. Antoniades DZ, Belazi M, Papanayiotou P. Concurrence of torus palatinus with palatal and buccal exostoses: case report and review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1998;85:552-7.

6. Barker D, Walls AW, Meechan JG. Ridge augmentation using mandibular tori. Br Dent J. 2001;190: 474-6.

7. Cantín M, Fernández RF, Rojas M. A proposed explanation for the development of the torus palatinus. Clin Anat. 2011;24(6):789-90.

8. Drennan MR. The torus mandibularis in the Bushman. J Anat 1937;72(1):66-70.

9. Singh GD. On the etiology and significance of palatal and mandibular tori. Cranio 2010;28(4):213-5.

10. Eggen S, Natvig B. Relationship between torus mandibularis and number of present teeth. Scand J Dent Res 1986;94(3):233-40.

11. García-García AS, Martínez-González JM, Gómez-Font R, Soto-Rivadeneira A, Oviedo-Roldán L. Current status of the torus palatinus and torus mandibularis. Med Oral Patol Oral Cir Bucal 2010;15(2):353-60.