| Objective To clarify the viability trends of three types of bone cells exposed to sodium fluoride. Methods In order to explore the changes of cell viability on the three major bone cell types exposed to different concentrations of sodium fluoride, mouse bone mesenchymal stem cells (bmscs)，as osteoblast progenitors, were induced into osteoblasts by mineralization induction agents containing dexamethasone, ascorbic acid, and p-sodium glycerol phosphate. raw264. 7 cells were induced to become osteoclasts by rankl induction, and idg-sw3 cells were induced into osteocyte by mineralization induction. Osteoblasts, osteoclasts and osteocyte were seeded into 96-well plates and exposed to 8 fluoride concentration gradients, respectively. Fluoride gradient included control group, low fluoride concentration (0. 1，0. 5，1，2 mg/L)，medium fluoride concentration (4,8 mg/L) and high fluoride concentration (16，32 mg/L). three types of cells were treated with fluorine for 1 day, 2 days and 4 days periods. in the end, the methyl thiazolyl tetrazolium (MTT) method was used to measure cell viability. Results After 2 days of fluoride exposure, 0. 5 and 1 mg/L fluoride significantly increased the viability of osteocytes，but the 8-32 mg /l dose of fluorine significantly inhibited the viability of osteoclasts and osteoblasts. After 4 days of fluoride exposure, 0. 1-2 mg/L fluoride treatment significantly increased the viability of osteocyte, the viability of osteoclasts treated with 1-4 mg/L fluoride was also significantly higher than that of the controls . Under treatment with 16 mg/L of fluoride, cell viability of osteocytes fell by 8. 6%，while viability of osteoclast and osteoblast sharply fell by 90. 8% and 97. 2%. Conclusion by comparison among three types of bone cell, osteoblasts indicated the narrowest range of fluoride-stimulating action，and significant inhibitory effect. osteoclasts were the most sensitive to the change of fluorine dose，and osteocytes had the strongest tolerance to toxicity of fluoride accumulation. |