Unicystic Plexiform Aameloblastoma

Abstract

Ameloblastoma is a true neoplasm of odontogenic epithelial origin. It has been categorized into four biologic variants-unicystic, solid, peripheral, and desmoplastic. Unicystic ameloblastoma (UA) is a benign epithelial odontogenic tumor of the jaw that commonly occurs in the second and third decade of life. It comprises approximately 6% of all ameloblastomas and is the least encountered variant of the ameloblastoma. UA refers to those cystic lesions that show clinical, radiographic, or gross features of a jaw cyst but on histologic examination show a typical ameloblastomatous epithelium lining the cyst cavity, with or without luminal and/or mural tumor proliferation. The term plexiform UA designates a plexiform type of epithelial proliferation occurring in the dentigerous cyst. The epithelium in this case proliferates in a restiform or network pattern. The purpose of this case report was to describe a case of unicystic plexiform ameloblastoma involving the crown of an unerupted mandibular third molar in an 18-year-old male patient which was clinically and radiographically diagnosed as a dentigerous cyst. The occurrence of unilocular radiolucency with impacted tooth may lead to an erroneous presumptive diagnosis of a dentigerous cyst by the clinician and result in undertreatment of the disease entity.