Abstract
A case of palatal polyp was found in a 2-year, 6-month-old Japanese boy. Histopathologically, it was diagnosed as peripheral developing odontoma, which occurs rarely in the oral region.The findings were :Intraoral examinations showed a gingival-colored mass with a smooth surface, measuring 5×3×3 mm on the palatal mucosa adjacent to the upper central primary incisors. Radiographic examination revealed a small calcified structure in the upper right central primary incisor root region, just underneath the base of the palatal polyp. The mass and the small calcified structure were removed at the same time and the specimen was examined histopathologically.Within the polyp, cylindrical epithelium cells, reminiscent of ameroblasts, were present. They were surrounded by mesenchymal connective tissue beneath the mucous membrane. There was odontogenic epithelial proliferation and fibrous tissue hyperplasia, but inflammatory cells were not observed.The small calcified mass in the polyp had structures of enamel, dentin, cementium and pulp tissue,so it was suspected to be a supernumerary tooth. However, the odontogenic epithelium and calcospherites surrounding the calcified mass, consequently, led us to considered it to be a peripheral developing odontoma.After surgery, no sign of recurrence has been observed.
