【摘要】 目的:通过分析正畸治疗引起的上颌中切牙牙根吸收的可疑相关因素,探讨各因素对牙根吸收影响的程度和大小,以期寻找有效的预测和评估因子。方法:随机选择病例资料完整的64例矫治已经结束的病例为研究对象,采用t检验、相关分析和多元逐步回归方法分析正畸治疗引起的上颌中切牙牙根吸收的可疑相关因素。结果:上颌中切牙牙根吸收的平均值为0.93mm。t检验结果显示上颌中切牙牙根吸收的大小与性别、拔牙与否和安氏分类的类型无关,相关分析结果为上颌中切牙牙根吸收的大小与疗程、方丝弓戴用的时间、根尖垂直向位移显著相关,多元逐步回归分析结果提示各相关因子的预测和评估的效率较低。结论:正畸治疗引起的上颌中切牙牙根吸收数量较小,目前尚无有效的预测和评估因子。更多还原

【Abstract】 Objective: To analyze the relationship between external apical root resorption(EARR) of maxillary central incisors and dubious risk factors,and to determine which factors could predict the extent of EARR.Methods: The complete records of 64 patients in whom the orthodontic treatment had been finished were selected.The risk factors and their relationship with the EARR of maxillary central incisors were analyzed with t test and correlation and regression analysis,respectively.Results: The mean shortening value of EARR of the maxillary central incisors was 0.93 mm,and there were no significant differences between male and female patients,between patients with and without extractions,and between patients with different Angle’s classes of malocclusion.Three variables,treatment time,placement time of rectangular wire,and vertical movement distance of the apex of the maxillary central incisors(Dy′),were significantly correlated with EARR.The coefficient of determination of 2 independent variables,placement time of rectangular wire and Dy′,was only 0.293.Conclusion: EARR resulting from orthodontic treatment is slight,and no predictor clinically useful for EARR has been found.更多还原