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目的 明确Ⅱ类颌间牵引对成人高角拔牙病例牙颌面垂直向的影响.方法 收集194例高角成人正畸拔牙病例,对治疗前后头颅侧位片的主要垂直向指标进行测量.根据正畸支抗类型和是否悬挂Ⅱ类牵引将研究对象分为4组:传统支抗不牵引组22人,传统支抗牵引组91人,种植支抗不牵引组35人,种植支抗牵引组46人.采用独立样本t检验评价传统支抗两组间和种植支抗两组间治疗后牙颌面垂直向变化的差异.结果 传统支抗牵引组MP-SN增大(0.5±1.3)°,PP-MP增大(0.2±1.5)°;传统支抗不牵引组MP-SN减小(0.2±1.6)°,PP-MP减小(0.5±1.6)°.这两个指标的组间差异具有显著的统计学意义(P＜0.05).而种植支抗两组患者各垂直向指标变化均不存在显著的组间差异.结论 传统支抗高角拔牙病例中Ⅱ类牵引的使用会造成一定程度的垂直向开大.而种植体支抗高角拔牙病例中,Ⅱ类牵引的使用并不能显著改变牙颌面的垂直向高度.“,”Objective To investigate vertical effects of Class Ⅱ elastics in dolichofacial adult orthodontic patients.Methods Hundred and Ninety-four successfully-treated high-angle adult orthodontic cases were recruited,their records examined,pre-and post-treatment lateral cephalograms traced.The subjects were divided into 4 groups according to the anchorage types and whether or not Class Ⅱ elastics were used during treatment.Conventional anchorage non-traction group has 22 subjects,conventional traction 91,Micro-implant anchorage (MIA) non-traction 35,MIA traction 46.Cephalometric measurements of the vertical dimensions of two conventional anchorage groups and two MIA groups were compared respectively with independent-sample t test.Results In patients treated with conventional anchorage,Class Ⅱ elastics group saw (0.5±1.3)° increase in MP-SN,and (0.2± 1.5)° increase in PP-MP,whereas non-elastics group saw (0.2±1.6)° decrease in MPSN,and (0.5±1.6)° decrease in PP-MP,with a significance level below 0.05.In patients treated with MIA,no significant difference was noted between those treated with and without Class Ⅱ elastics.Conclusions The use of Class Ⅱ elastics results in vertical opening of mandible in dolichofacial adult extraction cases treated with conventional anchorage.With the use of mini-implant anchorage,the vertical effects of Class Ⅱ elastics was not significant.