Peripheral odontogenic keratocyst.

The gingival cyst of the adult exhibits an epithelial lining that is essentially the same as the lateral periodontal cyst. Although the gingival cyst of the adult exhibits some morphologic variability, its lining is generally considered to be nonkeratinized. Nonetheless, rare cases of gingival cyst of the adult that exhibit a keratinized epithelial lining have been reported in the literature. There is now a growing tendency to consider this variant as a separate entity. This article describes six cases of gingival cysts that exhibit the histologic features of the odontogenic keratocyst. Evidence from this series suggests that the biologic behavior of this subset of gingival cysts is different from that of the generic gingival cyst of the adult and that the term peripheral odontogenic keratocyst more accurately describes this entity.