Effect of dental cyst epithelium-conditioned medium on collagenase production by periodontal ligament fibroblasts.

Seven dental cyst epithelia were cultured in vitro and the conditioned media were analyzed for periodontal ligament fibroblast collagenase production. All the cyst epithelium-conditioned media stimulated fibroblast collagenase production, indicating that dental cyst epithelium, which is considered to be identical to the cell rests of Malassez, might play a role in periodontal pocket formation.