A 53-year-old male visited a dentist for a routine checkup. Radiographic examination revealed bilateral well-defined radiopacities in the manidublar premolar region.
When questioned about these areas, the patient denied any history of symptoms. The patient also denied any history of trauma to the involved areas. The patient appeared to be in a general good state of health, with no significant past medical history.
The patient's dental history included regular dental examinations and routine dental treatment. At the time of the dental appointment, the patient was not taking medications of any kind.
The patient's vital signs were all found to be within normal limits. Examination of the head and neck region revealed no enlarged or palpable lymph nodes. Examination of the soft tissues of the oral cavity revealed no unusual findings.
Large, bilateral bony masses were noted on the lingual mandible in the premolar areas. Radiographic examination of the involved areas revealed well-defined, ovoid radiopacities superimposed over the roots of the premolars (see radiograph). The adjacent teeth were tested for vitality; all tested vital.
Based on the clinical information available, which one of the following is the most likely diagnosis?
- buccal exostoses
- periapical cemental dysplasia
- fibrous dysplasia
- torus mandibularis
- cemento-ossifying fibroma
- torus mandibularis
Torus mandibularis (also known as mandibular tori) is a common protuberance of bone that presents as a smooth enlargement of the lingual surface of the mandible above the mylohyoid line in the premolar region.
The cause of mandibular tori has long been debated and is currently believed to be multifactorial. It has been suggested that the formation of tori is a dynamic process that includes a hereditary component and is influenced by functional factors like masticatory stress.
Mandibular tori occur most often in adults. There is a slight male predilection and approximately seven to 10 percent of adults in the United States are affected.
Mandibular tori may occur unilaterally or bilaterally; over 90 percent of cases occur bilaterally. Mandibular tori vary in size and shape and may occur as solitary nodules or multiple lobules of bone. In rare cases, bilateral mandibular tori may become so large that they meet at the midline.
When palpated, mandibular tori feel rock hard. There are no symptoms associated with these bony growths.
The mucosa overlying mandibular tori typically appears intact and is normal in color. Ulcerations may occur if the mucosa is traumatized. Patients are typically unaware of the tori unless the overlying mucosa becomes ulcerated. The adjacent teeth are vital and there is no history of pain or sensitivity.
Mandibular tori are typically discovered during the oral examination. Radiographically, mandibular tori appear as ovoid radiopacities superimposed over the roots of the mandibular premolars. Tori predominantly composed of cancellous bone appear less radiopaque than tori composed of dense, compact bone. Such dense radiopacities may be confused with other radiopaque lesions that affect the jaws.
Diagnosis and treatment
Mandibular tori are benign lesions of little clinical significance. The diagnosis of mandibular tori is made based on the clinical and radiographic findings. Typically, no treatment for tori is indicated.
Mandibular tori may complicate the construction of dental appliances. Therefore, surgical reduction of these lesions to the level of surrounding bone may be indicated if a partial or complete denture is needed.
Joen Iannucci Haring, DDS, MS, is an associate professor of clinical dentistry, Section of Primary Care, The Ohio State University College of Dentistry.