尖牙垂直矩形附件位置及尺寸对隐形矫治器脱位力的影响

The influence of the position and size of the vertical rectangular attachment in canine on the dislocation force of the aligners

目的探讨尖牙上垂直矩形附件的位置及尺寸对无托槽隐形矫治器的垂直向及水平向脱位力的影响,以期为临床应用提供参考。方法本研究为实验研究,利用3D打印技术建立测试尖牙脱位力模型,将矫治器附件分成3 mm龈端组、3 mm切端组、5 mm龈端组及5 mm切端组,测试不同附件的垂直向及水平向的最大脱位力值,每组重复14次。结果垂直向脱位力测试显示:3 mm龈端组、3 mm切端组、5 mm龈端组和5 mm切端组的垂直向脱位力分别为(7.10±1.98)N、(7.39±0.41)N、(6.22±1.35)N和(6.38±0.70)N,其中3 mm切端组与5 mm切端组间差异有统计学意义(P=0.001);水平向脱位力测试结果显示:3 mm龈端组、3 mm切端组、5 mm龈端组和5 mm切端组的水平向脱位力分别为(3.40±0.34)N、(2.40±0.23)N、(3.85±0.24)N和(2.11±0.21)N,各组间均存在统计学意义差异(P<0.01)。结论尖牙切端设计垂直矩形附件时,3 mm附件的垂直向脱位力反而大于5 mm附件,在尖牙的龈端设计附件其所获得的水平脱位力大于切端。

Objective To investigate the influence of different positions and sizes of vertical rectangular attachments on vertical and horizontal dislocations in canines when using aligners,in order to provide reference for clinical application.Methods This study is an experimental research.The 3D printing technique was used to create a model for measuring the dislocation force in canines.The attachments were divided into four groups:a 3 mm gingival group,a 3 mm incisal end group,a 5 mm gingival end group,and a 5 mm incisal end group.The maximum values of dislocation force in both vertical and horizontal directions were measured within these groups.All tests were repeated 14 times for each group.Results In the vertical dislocation force test for canine,the measured value of the 3 mm gingival group,3 mm incisal group,5 mm gingival group and 5 mm incisal group were(7.10±1.98)N,(7.39±0.41)N,(6.22±1.35)N and(6.38±0.70)N,respectively.The difference between 3 mm incisal group and 5 mm incisal group was statistically significant(P=0.001).The measured horizontal dislocation force in 3 mm gingival group,3 mm incisal group,5 mm gingival group and 5 mm incisal group were(3.40±0.34)N,(2.40±0.23)N,(3.85±0.24)N and(2.11±0.21)N,the differences between 4 groups were all statistically significant(P<0.01).Conclusions The vertical dislocation force of 3 mm vertical rectangular attachments in canine is greater than that of 5 mm attachments,and the horizontal dislocation force of the gingival group is greater than that of the incisal group.