Cementifying fibroma presenting as proptosis

Cementifying fibromas are rare fibro-osseous tumors that arise from the periodontal ligament. These tumors are usually small, asymptomatic lesions noted on routine dental radiography, but they can develop into aggressive, expansile masses. The authors report the case of a 12-year-old boy with a tumor involving the maxillary, ethmoid, and frontal sinuses that extended to the right orbit, causing proptosis and disfigurement of the right side of his face. Removal of the tumor with facial reconstruction resulted in significant improvement of vision, despite long-standing disc edema and tension on the optic nerve. On histopathologic examination the lesion was found to be a cementifying fibroma.