Immunohistochemical detection of factors related to cellular proliferation and apoptosis in radicular and dentigerous cysts.

INTRODUCTION

This study proposed to investigate aspects of cell proliferation and death in the epithelium of radicular (RCs) and dentigerous (DCs) cysts.

METHODS

Serial sections of 17 RCs and 9 DCs were prepared for immunohistochemical detection of caspase-3, Bcl-2, and Ki-67 antigens.

RESULTS

Caspase-3 was detected mainly in the suprabasal and superficial epithelial cells of RCs and DCs, whereas Ki-67 was detected predominantly in the basal layer. Both markers had significant expression in hyperplastic epithelium related to an intense inflammation in the capsule. Immunoreactivity for Bcl-2 was restricted to the basal layer and was significantly higher in atrophic epithelium of DCs than that of RCs.

CONCLUSIONS

These results suggest that epithelial proliferation is balanced by apoptosis and that the presence of inflammation inhibits the Bcl-2 expression. DCs and RCs have different formation mechanisms but have similar biological behavior in the presence of intense inflammatory infiltrate.