OBJECTIVETo investigate the proliferative potential of the epithelial cells in odontogenic keratocyst, radicular cyst, dentigerous cyst and ameloblastoma.

METHODSDNA contents and ploidy of basal and spinous cells in keratocyst, radicular cyst, dentigerous cyst, and the peripheral column cells and central reticular cells in ameloblastoma were analysis respectively.

RESULTSThe more and higher DNA contents and the proliferating ploidy of keratocyst and ameloblastoma than those of radicular cyst and dentigerous cyst indicate the active proliferating potential. The spinous cells showed more active proliferating growth than the basal cells of keratocyst. The higher DNA contents of radicular cyst are related to the stimulus of the inflammation. The dentigerous cysts have more di-ploidy cells without active growth potential.

CONCLUSIONSThe active cell proliferating growth in keratocyst and ameloblastoma is probably the pathological basis of their local aggressive biological behavior.