Juvenile active ossifying fibroma with massive involvement of the mandible.

Fibro-osseous lesions of the maxillofacial complex are often difficult to diagnose from both a clinical and a histopathologic point of view. The parameters for the diagnosis of juvenile active ossifying fibroma are as follows: a patient under 15 years of age, localization of the tumor, the radiologic aspect, and the tendency to recur. Although many authors favor conservative surgery rather than radical en bloc resection, immediate recurrence characterized by a high aggressive growth rate and the absence of a distinct separation between the tumor and the adjacent bone requires ex- tensive surgery, with wide demolition of the involved bone.