Objective To isolate the periodontal ligament cells(PDLCs) and study the effect of high glucose concentration levels on the cellular activity and osteogenic differentiation of PDLCs from non-diabetic patients in vitro. Methods PDLCs were cultured for 14 days in 0 mg•L-1 glucose medium(C group), 1 100 mg•L-1 glucose medium(L group), and 4 500 mg•L-1 glucose medium(H group). Methyl thiazolyl tetrazolium(MTT) assay for cellular viability was performed. The osteogenic differentiation capacity of PDLCs was evaluated by alizarin red staining and alkaline phosphatase(ALP) activity assaying and real time-transcription polymerase chain reaction. Results H group significantly inhibited the proliferation of PDLCs and reduced the optic density of the MTT and ALP activity assay. The difference was significant(P
