2017 年 30 巻 2 号 p. 183-186
Ameloblastoma occurs most frequently in the jaws intraosseously. However, this odontogenic tumor rarely occurs in extraosseous soft tissue, and such cases are commonly referred to as peripheral ameloblastoma. As characteristic findings are commonly poor in this tumor clinically, it is difficult to diagnose correctly. We experienced a case of peripheral ameloblastoma in the lower gingiva of the canine area that was found by accident. The patient was a man in his 40s. A painless lesion with a papillary surface was found in the lingual gingiva of the mandibular canine, so it was considered to be a papilloma and was removed under local anesthesia. However, findings characteristic of ameloblastoma were obtained pathologically, so the case was diagnosed as peripheral ameloblastoma. No evidence of recurrence was found during eight months of observation after excision.