Squamous odontogenic tumor. A lesion of the periodontium.

The squamous odontogenic tumor (SOT) is a benign lesion of the periodontium most probably arising from the rests of Malassez. Most lesions are solitary tumors but multiple lesions may occur. There is equal distribution in the jaws with the posterior mandible and anterior maxilla, the most common sites. The majority of patients are under age 32 and there is no sex predilection. Radiographically the usual appearance is a triangular or semicircular radiolucency of alveolar bone with sclerotic and/or scalloped margins. Clinical findings include sensitivity of teeth, mobility and movement of teeth and deep pocket formation. The maxillary lesions tend to be more aggressive than those of the mandible, and extensive resection may be required. In most cases, however, conservative surgery appears adequate. The histopathologic findings are now clearly delineated so that the SOT should not be confused with ameloblastoma or epidermoid carcinoma.