Clinical and radiographic features of chronic monostotic fibrous dysplasia of the mandible.

Chronic untreated fibrous dysplasia of the mandible in a 40-year-old man is described, with emphasis on the radiographic findings. To the authors' knowledge, this is the first such case to be reported in the literature. Within this mature mandibular lesion, a large radiolucency was noticed, with the appearance of a simple bone cyst. The patient did not have any symptoms directly related to the mandibular lesion. Various aspects of the diagnosis, radiographic appearance and differential diagnosis are discussed. The information presented here will be useful for all dentists, oral and maxillofacial surgeons, physicians and other health care providers in identifying the appearance of chronic fibro-osseous lesions.