Rare, simultaneous, multiple, and recurrent mandibular bone cysts.

Simple bone cysts, also referred to as traumatic bone cysts, are benign connective tissue-lined cavities occurring most commonly in young people. Most of the time, they occur as solitary radiolucencies. In the jaws, they also have been reported to occur concurrently with benign fibro-osseous lesions. The radiographic appearance of simple bone cysts could be confused with other jaw cysts and benign tumors. This case report presents a patient who had 3 separate lesions simultaneously within the mandible. The right mandibular lesion presented as a multilocular radiolucency. The 2 left mandibular lesions were periapical, with mixed radiodensities and radiographically mimicked lesions of focal or periapical cemento-osseous dysplasia. More aggressive benign lesions of the jaw were initially included in the differential diagnosis, as well. A biopsy revealed the diagnosis of simple bone cysts in all 3 locations. Minimal surgical management resulted in complete recovery of these osseous defects only to recur in 2 years on the mandibular left premolar-molar region. A new biopsy confirmed that the lesion was a recurrent simple bone cyst. Simultaneous presence of benign cemento-osseous dysplasia was also considered, as it is known to coexist with the simple bone cysts.