ABSTRACT
<p><b>OBJECTIVE</b>To determine the effect of tea polyphenol (TP) on the proliferation of human periodontal ligament fibroblasts (HPDLFs).</p><p><b>METHODS</b>HPDLFs were primary cultured from tissue explants, and the cells of the 5th to 8th passages were used after immunohistochemical identification (with SABC method) of keratin and vimentin expressions. The cells were divided into 5 groups and treated with TP at 1, 0.5, 0.25, 0.125, and 0.0625 mg/ml, respectively, with another group without TP treatment as the blank control group. Cell counting and MTT colorimetric assay were performed to assess the cell proliferation, and flow cytometry was employed to determine the DNA content of the HPDLFs.</p><p><b>RESULTS</b>Different concentrations of TP all significantly increased the proliferation and DNA synthesis of the HPDLFs (P<0.05), and TP treatment at 0.5 mg/ml for 6 h produced the optimal effect.</p><p><b>CONCLUSION</b>TP has obviously effect in promoting the proliferation of HPDLFs.</p>