A keratoameloblastoma is a histologically variant of the ameloblastoma group, which varies in size and contains keratin material in the fibrous
connective tissue among cystic lesions. A keratoameloblastoma is a rare disease with only 13 cases reported in the literature since Pindborg’s first
report in 1970. A 41-year-old man visited, complaining of pus discharged from the right maxilla. He had been diagnosed with an odontogenic
keratocyst and was treated with cyst enucleation in the past. The clinical and radiology examination found evidence of recurrence and finally
diagnosed him with keratoameloblastoma after enucleation and biopsy. This report discusses the clinical, radiological and histological characteristics
of keratoameloblastoma and its treatment. In addition, we report another case of keratoameloblastoma that had transformed from an odontogenic
keratocyst.