直丝弓关闭曲法和滑动法的比较研究

Comparison of closing T loop technique and sliding technique using preadjusted appliance

目的 对直丝弓矫治器关闭间隙的两种方法 ,即关闭曲法和滑动法的优缺点进行评价。方法 利用三维座标测量仪 ,开发正畸牙移动的下颌测量系统 ,采用前瞻性配对设计 ,对 16例拔除 4个第一双尖牙的正畸病例进行测量研究。结果 关闭曲法组和滑动法组前牙后移的比率分别为0 5 5和 0 5 3 ,两组在消耗支抗方面差异无显著性 (P >0 0 5 )。滑动法比较有利于维持覆和切牙的位置。结论 滑动法在临床应用中显示出其多方面的优点 ,直丝弓矫治技术宜采用滑动法关闭间隙。

Objective To compare the difference between closing T loop technique and sliding technique.In anchorage demand and treatment outcome Methods Sixteen first premolar extraction cases were chosen and divided into two groups for prospective paired t test They were treated by one author using 0 022'×0 028' preadjusted appliances T loops were fabricated using 0 018'×0 025' s s wire Chinese NiTi coil springs and 0 019'×0 025' s s arch wire were employed in sliding technique group Treatment materials, steps and appliance design in both groups were standardized Measurements of dental model and cephalogram were taken Results In closing T loop technique group and sliding technique group, the ratio of anterior teeth movement was 0 55 and 0 53 respectively The difference was not significant ( P >0 05 ) L1MP angle decreased by 5 7° and 3 1° respectively during treatment ( P <0 05 ) Conclusion Demand on anchorage was not significantly different between two groups Sliding technique was more favorable in maintaining anterior teeth inclination