正畸牙槽骨改建中RANKL/OPG表达动态变化特征及牙周组织细胞凋亡观察

目的系统研究正畸牙槽骨改建过程中RNAKL/OPG的表达动态变化规律,以及对破骨细胞形成和骨组织改建的影响,同时观察牙周组织中细胞凋亡关键因子的变化特征。方法我们建立小鼠上颌左侧正畸模型,并在正畸开始后第5、7、14和21天进行连续观察,通过Micro CT分析各个时间点第一磨牙移动距离以及远中根压力侧牙槽骨变化。并通过HE染色和TRAP染色检测不同时间点远中根压力侧组织学和破骨方面的变化。进一步通过免疫组化染色和免疫荧光染色检测不同时间点远中根压力侧RANKL、OPG和Caspase3的表达变化。结果在正畸力施加后,小鼠左侧第一磨牙和第二磨牙之间的距离逐渐增加,第一磨牙远中根压力侧BV/TV降低,RNAKL和OPG表达逐渐升高,且在加力第7天RANKL表达出现高峰,随后OPG表达高峰出现在第14天,RANKL先于OPG出现表达高峰,并且伴随出现破骨细胞生成高峰。同时,牙周组织中细胞凋亡数量逐渐增加,牙齿移动明显。结论正畸过程中,RANKL/OPG表达变化呈现时序性特征性变化,同时伴随关键细胞凋亡分子的表达变化,其变化和牙槽骨改建和牙齿移动密切相关。

Observation of RANKL/OPG temporal expression and apoptosis of periodontal tissue during alveolar bone remodeling induced by orthodontic force

Objective To study the dynamic changes of RNAKL/OPG expression in orthodontic alveolar bone remodeling and its effects on osteoclast formation and bone tissue remodeling, to observe the change features of key factors in apoptosis in periodontium. Methods The left maxillary orthodontic model of mice was established and observed continuously on day 5, day 7, day 14 and day 21 after orthodontic treatment. The distance of the first molar movement and the change of alveolar bone in distal root pressure were analyzed by Micro CT. HE staining and TRAP staining were used to detect the histological and osteoclastic changes of the distal root pressure side at different time points. The expression changes of RANKL,OPG and Caspase3 were detected by immunohistochemical staining and immunofluorescence staining at different time points. Results After the orthodontic force was applied, the distance between the left first molar and the second molar increased gradually, the expression of RNAKL and OPG increased gradually in the distal root pressure side of the first molar, and the expression of RANKL reached a peak on the 7 th day after the application of orthodontic force. Then the peak of OPG expression appeared on the 14 th day. The expression peak of RANKL was earlier than that of OPG, accompanied by osteoclast formation peak. At the same time, the number of apoptosis in periodontal tissue increased gradually, tooth movement was obvious. Conclusion During orthodontic treatment, the expression changes of RANKL/OPG show temporal characteristic changes, accompanied by changes in the expression of key apoptotic molecules, and these changes are closely related to alveolar bone remodeling and tooth movement.