A case of ameloblastic fibroma appearing in the lower right second primary molor area is discribed. This case was the youngest child in Japan so far as reports on females are concerned.
On May 23, 1980, the patient, a 3-year-old girl, was submitted for treatment of retarded eruption of the lower right second primary molar.
On September 7, 1981, the tumor was removed under local anesthesia and the lower right second primary molar was erupting. Seven months later no reccurrence was observed.