Effect of fluoride on human tooth-germ cell proliferation and expression of related regulators in organ culture in vitro

Objective: To investigate the effect of fluoride on human tooth-germ cell proliferation and expression of related regulators. Methods: By using an organ culture model of human tooth-germ in vitro, the effects of low (10 mg·L^-1) and high (25 mg·L^-1) concentrations of fluoride on cell proliferation were observed histologically and the expression of cyclinD₁ and proliferating cell nuclear antigen (PCNA) were detected by immunohistochemistry staining and image analysis technique. Results: Fluoride inhibited cell proliferation and evidently decreased the expression of cyclinD₁ and PCNA. Conclusion: Fluoride may inhibit tooth-germ cell proliferation by inhibiting the expression of cyclinD ₁ and PCNA, which leads to the abnormal development of teeth.