Granular cell peripheral odontogenic fibroma.

A case of a peripheral odontogenic fibroma which contained aggregates of large granular cells is reported. These granular cells are similar to those previously described in the granular cell myoblastoma, congenital epulis and the granular cell ameloblastic fibroma. Deep extensions of the basal layer of overlying gingival epithelium, in double-strand fashion, are frequently observed in peripheral odontogenic fibromas. These strands closely resemble those seen in the tumor itself. On this basis, and as similar basal cell prolongations are seen in otherjaw lesions, it is postulated that residual ectomesenchymal influence may be responsible for inducing the basal cell proliferations in a similar manner to that which occurs during early embryonic dental development. This, it is suggested, might possibly be the histogenesis of the odontogenic epithelial strands in the peripheral odontogenic fibroma.