不同矫治器正畸后牙周骨组织压力侧的形态变化

Morphological changes of periodontal bone tissue at the pressure side after different orthodontic appliances

背景:Damon Ⅲ矫治器是近期矫治器改良的新方向。目的:观察不同矫治器正畸作用下兔牙周组织改建过程中压力侧组织病理学的变化。方法:64只健康大耳白兔随机等分为对照组、MBT矫治器组、Begg矫治器组和Damon Ⅲ矫治器组,后3组将MBT矫治器、Begg矫治器、Damon Ⅲ矫治器结扎在上颌切牙与第一磨牙之间,牵引上颌第一磨牙向近中移动1mm。结果与结论:矫治后7d时MBT矫治器组、Begg矫治器组、Damon Ⅲ矫治器组兔压力侧牙周骨组织骨小梁体积减少,骨小梁宽度变窄,间隙变宽(P<0.05),且成骨细胞与破骨细胞数量均明显增加(P<0.05)。矫治后21d时,与MBT矫治器组和Begg矫治器组相比,Damon Ⅲ矫治器组兔压力侧骨小梁体积减少,骨小梁宽度变窄,间隙变宽及成骨细胞与破骨细胞数量升高(P<0.05)。提示在正畸牙移动过程初期,MBT矫治器、Begg矫治器、Damon Ⅲ矫治器均有正畸效果,但Damon Ⅲ矫治器后期效果优于MBT矫治器和Begg矫治器。

BACKGROUND：Recently,Damon Ⅲ appliance is the new direction of appliance improvement.OBJECTIVE：To investigate the histopathological changes of rabbit periodontal bone tissue under the pressure side in the remodeling process after different appliance orthodontic.METHODS：Sixty-four healthy rabbits were randomly divided into four groups：control group,MBT appliance group,Begg appliance group and Damon Ⅲ appliance group.The MBT appliance,Begg appliance and Damon Ⅲ appliance were ligated between the maxillary incisors and first molars in order to tract the appliances move to the maxillary incisors for 1 mm.RESULTS AND CONCLUSION：At 7 days after correction,the volume of trabecular bone in the pressure side of rabbit periodontal bone tissue was reduced,the trabecular width was narrowed and the gap was broaden in MBT appliance group,Begg appliance group and Damon Ⅲ appliance group（P0.05）,and the amount of osteoblast and osteoclast was increased significantly（P0.05）.At 21 days after correction,compared with MBT appliance group and Begg appliance group,the volume of trabecular bone in the pressure side of rabbit periodontal bone tissue was reduced,the trabecular width was narrowed and the gap was broaden and the amount of osteoblast and osteoclast was increased significantly in the Damon Ⅲ appliance group（P0.05）.In the initial phase of orthodontic tooth movement,MBT appliance,Begg appliance and Damon Ⅲ of appliance have orthodontic effect,but the late effect of Damon Ⅲ appliance is better than that of the MBT appliance and Begg appliance.