大鼠正畸性牙根吸收及牙齿移动差异的研究

目的建立大鼠正畸性牙根吸收模型,比较一个加力周期内不同加力时间及不同加力力值时大鼠牙齿的移动差异及牙根吸收情况。了解时间、力值与牙齿移动及牙根吸收的关系。方法选择月龄相同,体质量相近的SD雄性成年大鼠建立正畸牙移动模型,按不同加力时间分为1、3、5、7、10、14d组,按加力大小分为40g、60g、80g力组。测量不同组别正畸牙移动量,采用连续切片观察牙根吸收情况。结果各组牙齿移动距离不同;牙根吸收主要表达在根中1/3区域;吸收程度与加力时间及力值有关。结论1、成功建立大鼠正畸性牙根吸收模型。2、不同加力时间及不同力值各组牙齿移动距离存在显著差异。3、不同加力时间及不同力值组牙根吸收存在规律性。

Study on orthodontic root absorption and tooth movement discrepancy in rats

Objective To establish an animal model of orthodontic root absorption,study the effects of orthodontic force and duration on tooth movement and root absorption and investigate the relationship among the force,duration and orthodontic root absorption.Methods Sixty-six male SD rats weighed (300±20) g were included.Orthodontic tooth movements of the rats under different force durations(1,3,5,7,10,14 days) and different values of orthodontic force(40 g,60 g,80 g) were measured,and the orthodontic root absorption in each group was investigated with HE staining.Results The distance of tooth movement in each group was different.Root absorption was commonly observed in the middle part of the root,the extent of which depended on the force and duration applied.Conclusion ①The experimental animal model of orthodontic root absorption was successfully established.②In the distance of orthodontic tooth movement there existed a significant difference.③Some regularity was found in orthodontic root absorption.