目的 探究无托槽隐形矫治器力学平台的测量误差来源,为后续优化力学测量平台的使用提供参考。 方法以原始模型 3D 打印树脂牙并组装形成力学测量平台的装配模型,对装配模型进行扫描,分别以原始模型(A 组)和装配模型(B 组)使用热压膜材料压制无设计量的隐形矫治器,通过对 A、B 组模型进行重叠分析和牙弓宽度测量,比较两组模型的匹配程度。 使用力学平台测量两组矫治器戴入后树脂牙的三维受力,比较两组牙齿受力情况的差异。 结果 测量和重叠分析结果显示,A、B 组模型平均存在-0. 126~ 0. 188 mm 偏差。 利用原始模型和装配模型制作的无设计量隐形矫治器戴入力学平台后,每个树脂牙均在三维方向上受到一定的力,使用原始模型制作的 矫治器产生的力更大。 除 33 和 32 唇舌向受力以及 32、31 和 46 垂直向受力,其余位点在两组矫治器戴入时牙齿受力差异均有显著的统计学意义(P<0. 05)。 结论 装配模型与原始模型之间存在差异,产生一定的系统误差。 为了减小安装过程导致的误差,需要在装配完力学平台后对树脂牙列进行三维扫描,并在装配模型基础上设计加工隐形矫治器。

To investigate errors of force measurement system for clear Aligners and provide references for optimizing the use of this system. Methods The original model was three-dimensional (3D) printed and assembled to form the assembly model of the force measurement system, then the assembly model was scanned. The original model (Group A) and the assembly model (Group B) were used to manufacture clear Aligners with no activation by thermoforming material respectively. Overlapping analysis and measurement of arch width were performed on Group A and B models, so as to compare whether two groups of models matched well. The force measurement system was used to measure the 3D force of the resin teeth after the clear Aligners were put on, and the differences of dental force between two groups were analyzed. Results The results of overlapping analysis and measurement of arch width showed that there was an average deviation of -0.126 mm to 0.188 mm in Group A and B models. When the clear Aligners made by the original model or assembly model were put on the force measurement system, a certain amount of 3D forces would be measured. The clear Aligners made by the original model produced larger forces than that made by the assembly model. Significant differences of the forces between two groups could be observed in most sites after the clear Aligners were put on, except the labial & lingual forces of tooth 33 or 32, and vertical forces of tooth 32, 31 or 46. Conclusions The discrepancy between the original model and the assembly model will cause certain systematic errors. In order to reduce the errors generated in installation procedure, it is necessary to perform 3D scanning of the resin dentition after assembling the force measurement system, and to design clear Aligners based on the assembly model.