成人正畸治疗前后牙根吸收的对比研究

目的:研究正畸治疗对成年患者牙根长度的影响。方法:以正畸治疗前后患者曲面断层片的上中切牙,上颌第一磨牙的近中颊根为研究对象,根据牙根发育程度将样本牙齿分组,分别测量正畸治疗前后患者曲面断层片的上中切牙牙尖至根尖以及上颌第一磨牙的近中颊尖至近中颊根根尖的长度,计算差值。结果:正畸治疗可引起牙根的变化,但A组(12～15岁开始治疗的)和B组(20～40岁)均无统计学意义,C组(40岁以上治疗的)吸收大于其他两组,组间比较有统计学意义。结论:成年人牙根吸收要多于青少年,疗程要长;上颌切牙最易发生根吸收,磨牙、前磨牙根吸收量非常低,且左右两侧无差异;女性根吸收的发生率很低,牙根只是微量的改变,所以正畸治疗是安全的。

Comparative study of root resorption before and after the treatment for adult orthodontic

Objective:To study the effect of root orthodontic treatment on root length of patients.Methods:Patients who were taken upper central incisor and mesiobuccal root canal in first maxillary molars of orthodontic were the research object.Patients were divided into different groups by degree of root development in which the length of upper cut tooth tip to the apical of panoramic radiographs,and of first molar mesial buccal root tip to near the apex were measured before and after orthodontic treatment.Results:The orthodontic treatment can cause changes in root,but the A group(12～15 years of age to begin treatment) and B(20～40 years old) were not statistically significant,C group(treated over 40 years old) absorption was statistically significant among groups.Conclusion:Adults root resorption is greater than the young,and course of treatment should be much longer.Maxillary incisor root resorption is most likely to occur,molars and premolars absorption is very low in which there is no difference between left and right.Women is very low incidence of root resorption,and only a small amount of change occur in the root in which the orthodontic treatment is safe.