Double idiopathic bone cavity with rare localization. Case report

SUMMARY: The mandibular bone depression belongs to the category of bone pseudocysts and is commonly known as “Stafne’s mandibular cyst, cavity or defect”. It usually presents as an asymptomatic, incidental radiologic finding and affects mostly middle-aged males.Radiographically, it appears as a round or ovoid radiolucency with thick and corticated border, located posteriorly,between the angle and the first molar area of the mandible. In the present paper the case of a patient whose panoramic radiograph showed two round-ovoid radiolucencies at the right angle of the mandible,approximately 1.0 cm below the inferior alveolar canal is presented. The distal one was well defined and measured approximately 0.65 x 0.50 cm. The mesial one appeared diffuse and measured approximately 0.65 cm in diameter. Based on the clinical and radiographic features,a provisional diagnosis of “idiopathic bone cavities”was made and regular follow up was proposed. A panoramic radiograph on the following year did not reveal any change in the position, shape, or size of the radiolucencies. Two years later, a CT scan of the mandible was performed as part of a consultation prior to dental implant placement. On axial CT images a depression of the lingual cortical plate was visible as well as one on the buccal cortical plate. A literature review of current theories on the pathogenesis, differential diagnosis and treatment of idiopathic bone cavities is also made.