The peripheral odontogenic fibroma.

An extensive review of the English-language literature has produced only five undoubted cases of peripheral odontogenic fibroma. This article reports ten new cases. The age and sex of the patients and the distribution by site and histology of the lesions are compared with those of other cases of bifrous tumors and neoplasms of odontogenic origin. It is postulated that this lesion may be more closely related to the fibrous euplis than was previously realized. Both lesions show hyperplasia of the basal layer of the covering ipithelium into double strands resembling odontogenic epithelium. It is suggested that this hyperplasia may be related to induction of the covering epithelium by primitive ectomesenchymal remnants within the gingivae. Proliveration of odontogenic rests within the peripheral odontogenic frbroma may be related to the same stimulus.