不同咀嚼压力对大鼠正畸移动牙压力侧牙槽骨改建的影响  

Effects of different masticatory pressures on alveolar bone remodeling in the pressure side during orthodontic tooth movement in rats

作　　者：田静 王子龙 肖丹娜[1] 范向飞[1] TIAN Jing;WANG Zilong;XIAO Danna;FAN Xiangfei(Department of Orthodontics,Tianjin Stomatological Hospital,Tianjin 300041,China;School of Medicine,Nankai University)

机构地区：[1]天津市口腔医院正畸科,300041 [2]南开大学医学院,300041

出　　处：《天津医药》2024年第4期367-372,共6页Tianjin Medical Journal

基　　金：天津市卫生健康科技项目(ZC20002)。

摘　　要：目的 研究不同咀嚼压力对大鼠正畸移动牙压力侧牙槽骨改建的影响。方法 选取8周龄雄性SD大鼠45只,按随机数字表法分为基线组5只、软食组20只和硬食组20只。基线组大鼠在实验初始处死、取材。软食组和硬食组建立上颌右侧第一磨牙近中移动模型,左侧不加力作为对照。各组喂以相应饮食,分别于加力后第3、5、7、14天各处死5只大鼠,取双侧上颌骨。Micro CT测量加力磨牙近中移动距离及压力侧牙槽骨骨体积/组织体积(BV/TV)、骨小梁分离度(Tb.Sp)和骨小梁厚度(Tb.Th)。抗酒石酸酸性磷酸酶(TRAP)染色计数破骨细胞数量;原位杂交染色观察细胞核因子-κB受体活化因子配体(RANKL)和骨保护素(OPG)mRNA表达随时间变化情况。结果 第14天时软食加力组牙齿移动距离小于硬食加力组(P<0.05)。软食加力组与硬食加力组压力侧牙槽骨BV/TV、Tb.Sp、Tb.Th差异无统计学意义。细胞计数和原位杂交结果显示,在第5、7天,软食加力组的破骨细胞数量和RANKL/OPG比值均低于硬食加力组(P<0.05)。结论 较小的咀嚼压力会减低大鼠正畸牙压力侧牙槽骨中的破骨活动,减小牙齿移动距离。Objective To study the effect of different masticatory pressures on alveolar bone remodeling in rats with orthodontic moving teeth.Methods Forty-five male SD rats aged 8 weeks were randomly divided into 3 groups:the baseline group(n=5),the soft diet group(n=20)and the hard diet group(n=20).Rats in the baseline group were sacrificed at the beginning of the experiment.The experimental rat models of right upper first molar movement were established in the soft diet group and the hard diet group.Left side of the maxillary was used as the control group.Each group was fed with corresponding diet.Five rats were sacrificed in each group on the day 3,day 5,day 7 and day 14 after orthodontic treatment respectively.Micro CT was used to measure the mesial movement distance of molar,bone volume/tissue volume(BV/TV),trabecular separation(Tb.Sp)and trabecular thickness(Tb.Th)of the alveolar bone on the pressure side.The number of osteoclasts in alveolar bone was counted after TRAP staining.In situ hybridization was used to detect the expression of RANKL and OPG.Results The amount of tooth movement was smaller on day 14 in the soft diet group than that of the hard diet group(P<0.05).There were no significant differences in BV/TV,Tb.SP and Tb.Th between the soft diet group and the hard diet group.TRAP staining and in situ hybridization showed that the number of osteoclasts and the RANKL/OPG ratio on day 5 and day 7 were lower in the soft diet group than those of the hard diet group(P<0.05).Conclusion The osteoclast activity in the alveolar bone on the pressure side of the orthodontic tooth is decreased and the tooth movement is inhibited under lower masticatory pressure.

关 键 词：咀嚼 压力 牙齿移动技术 正畸学 破骨细胞 骨保护素 细胞核因子-κB受体活化因子配体 

分 类 号：R783.5[医药卫生—口腔医学]