[The ameloblastic fibro-odontoma--an odontogenic mixed tumor progressing into an odontogenic sarcoma].

A case report is given on the rare course of an ameloblastic odontoma which originated from the right mandible in a girl at the age of 14. During the follow-up of 12 years there where 4 recurrences with a change in the histological findings. While ameloblastic epithelial complexes were found to be ever decreasing, there was, on the other hand, an increase in the mesenchymal component with foci of a marked proliferation of spindle cellular fibroblastic elements. Finally the condition progressed to an ameloblastic odontosarcoma appearing as a pleomorphic fibrosarcoma with a local metastasis. The clinical behaviour correlated with the histopathological findings.