Abstract:

Objective: The objective of this studywas to observe the interstitial cell of ameloblastic fibroma (AF) and ameloblastic fibro- sarcoma (AFS) and elucidate their biological characters.Methods: 11 cases of AF (in these 3 cases recurred) and 3 cases of AFS (in these 3 cases recurred and changed malignantly) were stained by HE, scanned by lightmicroscope, in which 5 cases of fresh tumor tissue, including 3 cases of AF and 2 cases of AFS, were scanned by the electric microscope.Results: Comparing with AF, interstitial cells of AFS increased, and atypical cells were usually present. Fibroblasts, fibrohistocytes, histocytes, un- differentiated mesenchymal cells and myofibroblasts were also found in the tumor tissue. The ameloblastic epitheliums was lack in 2P3 AFS.Conclusion: Decreased or lack epithelia may be associated with excessive hyperplasia in AFS. Interstitial cells of AFS may transform malignantly due to various stimulation.

Key words: ameloblastic fibroma, ameloblastic fibrosarcoma, odontogenic tumor