Tip-Edge与MDD矫治器排齐整平阶段切牙三维移动变化的对比研究

摘要

比较Typodont模型上Tip-Edge和MDD矫治器排齐整平阶段切牙的三维移动变化,为差动直丝弓矫治技术的改良及应用提供参考.选用10副同一型号的安氏Ⅱ类1分类错(牙合)Typodont上下颌模型,均拔除上下第一前磨牙,分成Tip-Edge和MDD两组,每组5个样本.使用0.41 mm澳丝排齐整平上下牙列,45℃恒温分别水浴20、40 min,利用ATOS流动光学三维扫描仪对实验初始模型及各阶段水浴后模型进行三维扫描,并以Typodont颌架底座定位确定水平向、矢状向和垂直向.Geomagic软件以三维坐标系统为重叠标志,将每次水浴后的三维数字模型与初始模型重叠.重叠后通过色图分析得出各切牙标志点水平向、矢状向及垂直向的移动变化.使用SPSS17.0软件进行统计分析.Tip-Edge组与MDD组各切牙标志点水浴20 min后在水平向、矢状向及垂直向均有移动；水浴40 min后移动量增大.从两次水浴后所得数据来看:水平向,75％的标志点正方向移动,84％的数据无统计学差异(P＞0.05)；矢状向,94％的标志点唇向移动,88％的数据无统计学差异(P＞0.05)；垂直向,所有标志点均为龈向移动,94％的数据无统计学差异(P＞0.05).从排齐整平阶段来看,Tip-Edge组与MDD组各切牙标志点移动量组间无统计学差异(P＞0.05).MDD和Tip-Edge矫治器在排齐整平过程中,对切牙三维方向移动的控制无明显差异.MDD矫治器打开咬合的作用有待进一步临床及实验验证.%The aim of this work is to compare the three-dimensional movement of incisors when applying TipEdge and MDD appliances in the alignment and leveling stage and provide reference to the improvement and clinical application of differential straight wire appliance.Ten of the same type of angle Ⅱ classification Ⅰ maxillary and mandibular Typodont models were chosed,and the first premolars were extracted.The samples were divided into two groups:Tip-Edge group and MDD group,each group had 5 samples.Australian wires of 0.41 mm were used to align the teeth while bathed in a constant temperature of 45 ℃ for 20 min and 40 min.ATOS flowing optical scanner was used to scan the models of the Tip-Edge and MDD group before and after each water bath,and the horizontal sagittal and vertical three dimensional system was established.Geomagic software was used to overlap the three dimensional digital models that were taken before and after each water bath,the sign points' changes were qualified by the color map.SPSS17.0 package was used for statistical analysis.Each sign point of the two groups had moved in the horizontal,sagittal,and vertical directions after incubated in the water bath for 20 min,and 40min.The amount of movement was increased.According to the data after the water bath,we can draw following results:Horizontal:75％ of the sign points moved in the positive direction,84％ of the data had no statistical differences (P ＞ 0.05) ; Sagittal:94％ of the sign points moved libially,88％ of the data had no statistical differences (P ＞ 0.05) ; Vertical:All sign points moved to the gingival,94％ of the data had no statistical differences (P ＞ 0.05).Judging from the entire alignment and leveling stage,there were no statistical differences between the two groups of inoisors' movement (P ＞ 0.05).The ability to control incisors' three dimensional movement of MDD and Tip-Edge appliances in the alignment and leveling stage had no significant differences,and MDD appliance' effect of bite-opening still need further clinical and experimental verifications.