Cyst-Resembling Fibrous Dysplasia of the Mandible: A Case Report.

Fibrous dysplasia (FD) is a rare fibro-osseous condition usually occurring in the maxilla. FD lesions typically exhibit "ground-glass" radio-opacity, asymptomatic swelling, and bony expansion; however, lesions may manifest in different forms. A 29-year-old woman was referred with a cyst-suspected lesion located at the root apex of the mandibular premolar without expansion. An incisional biopsy was performed, which finally diagnosed the cyst-resembling lesion in the radiograph as FD. Consequently, unnecessary endodontic treatment of the related teeth was prevented. FD may occur with skin and endocrine features, termed McCune-Albright syndrome (MAS). Therefore, comprehensive and systemic screening for MAS should be performed when FD is encountered in dental clinics. Clinicians should recognize this less common presentation of FD in the clinical, radiographic, and histopathological fields to handle this diagnostic challenge.