Gingival cyst in adults.

A retrospective study is reported of 14 cases of gingival cyst of adults. Clinical data were pooled with well-documented cases in the literature. Most cases occurred in the 5th and 6th decades and in the premolar-canine-incisor area. Microscopically, the epithelial lining ranged from a thin, flat to cuboidal layer, 1-3 cells thick, resembling reduced enamel epithelium, to a nonkeratinized stratified squamous epithelium without rete ridges, of about 5-6 layers. Epithelial cells were frequently atrophic and this could involve the full thickness of the epithelium leaving an amorphous band of eosinophilic material. Plaque-like epithelial thickenings are sometimes present. Multicystic or "botryoid" forms may occur. The cysts are of developmental origin, arising either from basal cell extensions of overlying epithelium; or from postfunctional odontogenic epithelial residues of the dental lamina or rests of Malassez; or from junctional epithelium in the gingival crevice. The latter theory of origin is favored.