Objective To select three kinds of perforation repair materials, mineral trioxide aggregate（MTA）, Z350, amalgam. And to evaluate the cytotoxicity of three kinds of perforation repair materials on human periodontal ligament fibroblasts（HPDLF） in vitro. Methods The proliferation of HPDLF to three perforation repair materials were examined by methyl thiazolyl tetrazolium（MTT） assay at 1, 3 and 5 days. The mRNA expression levels of bone -associated alkaline phosphatase（ALP） and osteocalcin（OC） were determined using a real -time quantitative polymerase chain reaction（PCR）. Results MTA shew almost no inhibition to HPDLF, the expression of ALP mRNA and OC mRNA in the HPDLF cultured on MTA were higher. Z350 induced a slight inhibition to HPDLF, and the expression of ALP mRNA but there was no difference in the expression of OC mRNA. Cell proliferation was significantly impaired by amalgam with grade 3, and the expression of ALP mRNA and OC mRNA were significantly reduced. Conclusion MTA have minimum cytotoxicity on HPDLF and can promote cell differentiation and regenerate of periodontal tissue. Z350 have lower cytotoxicity on HPDLF. Amalgam show highest cytotoxicity on HPDLF in the three materials and inhibit cells differentiation.
