磁性附着体模拟静磁场对成骨细胞增殖活性和周期分布及凋亡率的影响

目的研究不同强度磁性附着体模拟静磁场对成骨细胞增殖活性、细胞周期及细胞凋亡的影响。方法通过模拟Magnedisc 800磁性附着体静磁场，对体外培养的SD大鼠成骨细胞进行3种强度（12.5、125、250 mT）、持续不同时间的静磁场加载，检测成骨细胞的增殖活性，流式细胞术分析细胞周期分布和细胞凋亡率。结果成骨细胞加载3种强度的静磁场1、3、5、7、9 d后，细胞增殖活性未发生明显改变，各组细胞生长趋势基本一致，静磁场作用无明显的剂量- 效应关系。成骨细胞加载1、3、5、7 d后，未发现静磁场对G0 /G1期、S期、G2/M期细胞百分比、增殖指数及细胞凋亡率产生明显影响。结论磁性附着体静磁场在闭合磁路、磁体和衔铁的闭合过程中以及开放磁路下，对成骨细胞的增殖均无明显的促进和抑制作用，未改变细胞的周期分布和促进细胞凋亡的发生。

Effects of simulating static magnetic fields of magnetic attachments on osteoblasts proliferation, cell cycle distribution and apoptosis ratio

OBJECTIVE: To investigate the effects of the static magnetic field (SMF) generated by dental magnetic attachments on osteoblastic proliferations, cell cycle distribution, and apoptosis ratio. METHODS: By simulating those of the closed-field, the closure process and the open-field Magnedisc 800 magnetic attachments respectively, the in vitro cultured rat osteoblasts were exposed continuously to 12.5, 125, 250 mT SMF. The effects of the SMF on the proliferation of the cells were examined. MTT colorimetry test was performed to detect the effect of the SMF on the vitalities of cells. Flow cytometry was utilized to analyze the cell cycles and cell apoptosis rates. RESULTS: The SMF exposure didn't change the vital osteoblasts number, the cell cycle distribution and proliferation activities of osteoblasts. The cell apoptosis situation were not observed statistical differences. CONCLUSION: No matter the closed-field, the closure process and the open-field magnetic attachments respectively, continuous simulating SMF-stimulation of magnetic attachments couldn't change osteoblasts proliferation activity, cell cycle distribution, and apoptosis ratio.