釉基质蛋白衍生物对大鼠牙移动后复发和牙根修复的影响

目的:观察釉基质蛋白衍生物对大鼠正畸牙移动后早期复发和牙根吸收的影响.方法:选用20只10周龄雄性SD大鼠,实验组和对照组各10只,在左上第一磨牙施加100 g力,使其近中移动,加力14d后拆除装置.自拆除加力装置起,实验组局部注射釉基质蛋白衍生物,对照组不注射任何药物.分别于拆除装置后当天及第14天分别行Micro-CT活体扫描,分析牙根吸收陷窝以及牙移动距离的变化.采用SPSS19.0软件包对数据进行统计学分析.结果:拆除装置14 d后,实验组与对照组牙根吸收陷窝体积修复量分别为(0.0295±0.0052) ×1 07 μm3、(0.0189±0.0086)×107 μm3;牙移动后复发距离及复发百分率分别为(0.089±0.005)mm、(64.76±3.63)％和(0.127±0.010)mm、(92.28±1.90)％.统计学分析表明,拆除装置14 d后,牙根吸收陷窝体积修复量、牙移动后复发距离及复发百分率均有显著差异(P＜0.05).结论:一定浓度的釉基质蛋白衍生物可在一定程度上加强大鼠正畸移动后牙根吸收后修复效应,减弱牙移动后早期复发.

Effects of EMD on relapse and root repair after orthodontic tooth movement in rats

PURPOSE:To study the effect of enamel matrix derivative (EMD) on root repair and tooth movement relapse after orthodontic tooth movement in rats.METHODS:Twenty 10-weeks old male rats were divided into experimental and control group randomly (n=10).100 g force was exerted to the left maxillary first molars for 14 days and then removed.EMD was injected in rats in the experimental group since appliance was removed.The control group received no injection.Micro-CT was taken to analyze the changes of root resorption volume and distance of tooth movement.The differences were analyzed by SPSS19.0 software package.RESULTS:Fourteen days after device removal,the repair volume of root resorption lacunae in the experimental group and the control group were (0.0295±0.0052)×107 μm3,(0.0189±0.0086)×107 μm3,respectively.The relapse distance and relapse percentage after tooth movement were (0.089±0.005) mm,(64.76±3.63)％,(0.127t0.010) mm and (92.28±1.90)％,respectively.Statistical analysis showed the repair volume of root resorption lacunae,the relapse distance and relapse percentage were statistically significant 14 days after device removal (P＜0.05).CONCLUSIONS:EMD can enhance the effect of root repair and decrease early relapse after orthodontic tooth movement in a certain extent.