1998 年 37 巻 6 号 p. 683-684
A case of ameloblastoma of the maxilla is presented. Its incidence is high in the mandible, but extremely low in the maxilla. Needle aspirates of the tumor revealed some dyskeratotic cells and tight clusters of squamous-like cells. Histopathogically, the tumor was characterized by abundant densely collegenous stroma with small nests and strands of odontogenic epithelium. Odontogenic epithelium of ameloblastoma differentiated into squamous epithelium. The cytologic features of ameloblastoma are diagnostic, and incorrect diagnosis may be prevented if sufficient attention is paid to determining the benign squamous differentiation of odontogenic epithelium.