Les Torus ou Torii de la cavité buccale, pourquoi ?

Early recurrence of mandibular torus following surgical resection: A case report

INTRODUCTION AND IMPORTANCE

Tori are benign bony outgrowths that occur in different locations along the mandible and maxilla. Their origin is still uncertain; however, various hypotheses have been put forward, including male gender or mechanical overload. Recurrence of a torus after surgical resection is rarely described, and even less rapidly after a procedure.

CASE PRESENTATION

We present here the case of a 52-year-old patient who presented voluminous mandibular tori on the lingual side. The tori recurred very rapidly after the first resection surgery and with the same initial volume. Pathological examinations confirmed the histological type. The identified risk factors were excessive fish consumption, occlusal overload factors, and male gender. The patient then underwent a second surgery associated with a mouth guard in order to treat bruxism. There was no recurrence after one year of follow-up.

CLINICAL DISCUSSION

This case report highlights the fact that there is still a lack of understanding of the risk factors associated with torus. However, several studies have been able to understand certain genetic or dietary mechanisms in the genesis of these exostoses.

CONCLUSION

This case emphasizes the importance of mechanical overload in the recurrence of exostoses, which, coupled with dietary, gender, and ethnic factors, may be responsible for recurrence in this patient. The detection of factors associated with the risk of recurrence is a major challenge.

Asymmetric bone remodeling in mandibular and maxillary tori

OBJECTIVES

Tori are frequent paucisymptomatic bony outgrowths of the oral cavity in three locations: torus palatinus (TP), mandibularis (TM), and maxillaris (TMax). Their usually described histological characteristics are unspecific: normal cortical bone with more or less trabecular bone. The aim of this study was to describe tori's specific morphological and histomorphometric characteristics.

MATERIALS AND METHODS

Histological characteristics in a series of 18 tori collected after surgical removal were analyzed. Microcomputed tomography provided a 3D analysis. Mineral apposition rate (MAR) was measured after double tetracycline labeling. Osteoid tissue was identified by Goldner's trichrome and osteoclasts by the tartrate resistant acid phosphatase identification in undecalcified sections. Iron and aluminum were detected by histochemical staining methods. Osteoid thickness and MAR were determined at the outer surface of the torus and in the Haversian canals.

RESULTS

Tori appeared made of lamellar Haversian bone in 16/18 cases. Osteoid thickness did not differ between the outer surface and within the canals. An asymmetric bone remodeling was observed in the Haversian canals of 15 tori: osteoid seams were deposited on the side close to the free torus surface, and Howship's lacunae with numerous osteoclasts were observed on the opposite side. A high MAR was found at the surface of the tori and within the canals. There was no iron or aluminum deposit.

CONCLUSIONS

Tori may be characterized by a specific asymmetric bone remodeling which seems to determine their shape.

CLINICAL RELEVANCE

This finding could constitute a specific histological feature allowing to differentiate tori from exostoses. Graphical abstract.