正畸治疗中拔牙与牙根吸收关系的临床研究

目的评价拔牙对正畸治疗中的牙根吸收的影响。方法选取120例年龄在11～18岁经方丝弓矫治器固定矫治治疗的青少年,分为拔牙组和不拔牙组,两组病人治疗前后分别拍摄全口曲面断层片,牙根形态按等级分级,计算机进行统计分析各等级频数分布变化。结果两组病例在治疗后牙根吸收均以1、2级居多、拔牙组治疗后牙根3、4级吸收多于未拔牙组,两组之间的差异有显著性(P<0.001)。结论拔牙治疗会加重正畸治疗中的牙根吸收。

A Study of Relationship Between Extraction or Nonextraction and Root Resorption during Orthodonctic Treatment

Objective To determine the relationship between extraction or nonextraction and root resorption during orthodonctic treatment. Methods 120 Chinese children 11-18 years old with fixed orthodonctic treatment by Edgewise appliance were divided into two groups. The control group received nonextraction treatment while the experimental group received extraction treatment. The measurements of root degrees of all visual root shape on panoral radiographs taken before and after orthodonctic treatment were analysed for the distribution changes of root resorption in both groups. Results An increasing percentage of root resorption occurred during orthodontic treatment in the extraction group.The 1,2 degrees occurred more frequently. Compared with the 3,4 degrees,there was a higher rale in the extraction group. The differences seemed to be statistically significant between the two groups. Conclusion Extraction treatment could increase root resorption degrees during orthodontic treatment.