In this paper, we report the clinical course of a 11-year-old boy with an ameloblastic fibrodentinoma developing in the right side of the mandible. Clinically, there were no specific findings, except for an unerupted right mandibular first molar. Panoramic radiography and dental computed tomography revealed a well-defined radiolucent lesion with small calcified particles in the right side of the mandible. Moreover, an impacted tooth, which appeared to be the unerupted first molar, existed below the radiolucent lesion. A biopsy was performed, and the lesion was histopathologically diagnosed as ameloblastic fibrodentinoma. The tumor was removed with preservation of the impacted tooth under general anesthesia. As of 3 years after surgery, there have been no signs of recurrence, and the impacted tooth has erupted spontaneously in the dentition and functions as the first molar.
