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The age of the patient, the location and the unilocular radiolucency are all supportive of this diagnosis and therefore should stay on the differential diagnosis. The lack of expansion and the lack of association with an impacted tooth argue against the diagnosis of a unicystic ameloblastoma since 90% of these cases present looking like a dentigerous cyst.
Ameloblastoma is one of the most common benign neoplasms of odontogenic origin. It accounts for 11% of all odontogenic neoplasms. It is a slow-growing, persistent, and locally aggressive neoplasm of epithelial origin. It affects a wide range of age distribution but is mostly a disease of adults, at an average age of 33, with equal sex distribution. The unilocular radiolucency is more consistent with unicytic ameloblastoma. 90% of unicytic ameloblastomas are associated with the crown of an impacted tooth. The other 10% are uniloculr radiolucency usually associated with teeth such as between teeth. The patients constituting this group are around 14-20 years of age. Curettage is the treatment of choice for luminal and plexiform types of unicytic ameloblastomas and en-bloc or resection are an option for the mural type. The recurrence rate ranges from 6-35% depending on the type.