拔牙矫治后前牙根尖移动量与牙槽基骨突度改变量的相关性研究

Study on the correlation between the movement of anterior tooth apex and the change of alveolar convexity after extraction treatment

目的:探讨拔牙矫治病例前牙根尖点移动量与牙槽基骨突度改变量的相关性,为临床矫治设计与预后分析提供参考依据。方法:随机选择拔牙矫治完成病例39例,以Na-Po平面为基准平面,分别测量上、下前牙根尖点移动量,以及上、下基骨牙槽座点的突度改变量。然后通过对根尖点移动量与其相应基骨牙槽座点突度改变量的相关性统计分析,评价二者之间的相关性。结果:上颌中切牙根尖点移动量与上颌基骨牙槽座点的突度改变量具有明显的相关性(r=0.596,P<0.01),可以建立二者之间的直线回归方程y=0.586x-0.504。下颌中切牙根尖点移动量与下颌基骨牙槽座点的突度改变量的相关性不显著(r=0.209,P>0.05)。结论:上颌中切牙根尖点的内收可以带来上颌前部基骨的内收效果;反之,基骨的突度会增加。

Objective ：To investigate the correlation between the movement of anterior tooth apex and the change of alveolar convexity after extraction treatment to provide data for the orthodontic treatment. Methods： 39 patients received extraction treatment were randomly chosen. Conventional eephalometric analysis was performed to investigate the movement of anterior teeth apexes and the changes of A,B point from Na-Po plane as the datum plane. The cor- relation analysis was used to investigate the correlation between the movement of teeth apexes and change of alveolar convexity. Results： A high correlation was shown between the movement of upper incisor apexes and the change of A -point（r =0. 596, P 〈0.01）. The linear regression equation（y =0.586x-0. 504） was established between them. The correlation between the movement of lower incisor apexes and the change of B-point was not statistically significant（ r = 0. 209, P 〉 0.05 ）. Conclnsion： The retraction of upper incisor apex can lead to decrease of anterior maxillary convexity. Otherwise, the anterior maxillary convexity could increase.