Incidence of epithelial atypia in radicular cysts: a preliminary investigation.

Histologic sections of 100 radicular cysts were scored for epithelial atypia, inflammation, and presence of other histologic features. No atypia was found in 32 cases. In 34 cases, atypia occurred in epithelium that was heavily infiltrated with chronic inflammatory cells. There were 26 cases of slight atypia, six cases of moderate atypia, one case of severe atypia, and one case that appeared to be carcinoma arising in a cyst wall. There was no evidence that inflammation in the connective tissues occurred more frequently or was more severe in cases that exhibited greater degrees of atypia.