摘要
目的 通过一个前瞻性随机临床对照试验来比较采用生理性支抗Spee氏弓矫治系统（Physiological Anchorage Spee＇s Wire System,PASS）和MBT滑动直丝弓技术矫正完成的拔牙病例的上中切牙转矩,以比较两种不同矫正系统在上前牙内收过程中对于上前牙的转矩控制的效果.方法 设计临床随机对照试验,收集安氏Ⅰ类和Ⅱ类错[牙合]畸形需要拔牙矫正的病例.病例纳入标准：汉族;安氏Ⅰ类或Ⅱ类;恒牙列;设计上颌拔除两颗第一前磨牙;上颌支抗设计为中度或强支抗.研究收集并完成矫正病例40例,随机分组以年龄、性别作为分层依据,采用随机信封进行分层随机化分组,PASS组19例,其中男6例,女13例;MBT组21例,男8例,女13例.两组患者分别应用两种不同的矫治技术完成正畸矫治.采集患者治疗后的头颅侧位片及牙[牙合]模型,并进行测量分析.结果 通过数字化三维模型测量,测得矫正后PASS组患者的上中切牙相对于解剖[牙合]平面的转矩角度值为（8.7±5.5）°,而MBT组为（5.3±4.4）°,P=0.036.与以往研究得出的中国人正常合上中切牙转矩的均值（10.8±3.1）°相比较,PASS组与正常[牙合]均值间的差异不具备统计学意义的差异,而MBT组与正常[牙合]均值间的差异则具备统计学意义的差异.二维头颅侧位片测量两组患者切牙唇面切线与眶耳平面的后下夹角,PASS组为（91.5±6.5）°,MBT组为（87.8±8.6）°,P=0.141.结论 从三维模型的测量结果来看,与MBT技术相比较,PASS技术矫正完成的病例其前牙的转矩值更接近于正常[牙合]人群.对于上颌拔牙病例而言,由于PASS技术将前牙托槽的槽沟尺寸减小为0.020英寸×0.027英寸,减小了弓丝与槽沟间的余隙,从而更利于上前牙的转矩控制,避免其在内收过程中过于舌倾.
Objective The aim was to compare the finishing inclination of the upper central incisors achieved with PASS（Physiological Anchorage Spee＇s Wire System） or MBT technique through a prospective randomized controlled study.Methods Forty patients of Han Chinese with Angle＇s Class Ⅰ/Ⅱ malocclusion who required four premolars extraction treatment were enrolled and randomized to 2 treatment techniques：PASS technique （n=19,including 6 males,13 females） and MBT technique （n=21,including 8 males,13 females）;the groups were stratified by sex,starting age and anchorage need.The post treatment lateral eephalograms and dental models were used for analysis.Results The 3D digital model analysis showed that the upper central incisor inclination relative to anatomical occlusal plane（（U1/OP） in PASS group,averaged （8.7 ± 5.5） °,was larger than mean U1/OP（5.3±4.4）° in MBT group （P=0.036）.Compared with Chinese norm presented in the literatures（10.8± 3.1）°,no statistically significant was detected between PASS group and Chinese norm,but statistically significant was found between MBT group and Chinese norm.The angle formed by the tangent line of U1 labial crown contour and the FH line in post-treatment lateral cephalograms was（91.5±6.5）° in PASS group,and （87.8±8.6）° in MBT group （P=0.141）.Conclusions The measurement results from 3D models showed that the finishing inclination of upper center incisor in PASS group was closer to the Chinese norm than that in MBT group.This might,to some extent,indicated that smaller play of the bracket in PASS appliance achieved by the reduced size of bracket slot （0.020 inches×0.027 inches） helped in better torque control of anterior teeth during retraction.
出处
《中华口腔正畸学杂志》
2017年第3期121-127,共7页
Chinese Journal of Orthodontics
基金
北京大学口腔医学院临床新技术新疗法项目（PKUSSNCT2014A10）
首都临床特色应用研究项目（z141107002514054）
国家国际科技合作项目（2014DFA31800）
