Odontogenic fibroma.

The odontogenic fibroma is a rare tumor that has generated controversy, perhaps disproportionately to its importance in the family of odontogenic tumors. The clinical and radiographic features are well documented but the histologic aspects have generated controversy. The behavior is benign, and published accounts indicate a low recurrence rate following treatment by curettage. The tumor recognized by the World Health Organization (WHO) is the legitimate odontogenic fibroma. Histologic variants include the granular cell type and the hybrid odontogenic fibroma giant cell-like tumor. Although the extraosseous "peripheral" odontogenic fibroma presents as a gingival enlargement clinically indistinguishable from other gingival lesions, its histomorphology is similar to the central tumor. A normal dental follicle around the crown of an unerupted tooth may histologically mimic the odontogenic fibroma and other odontogenic tumors.