中文摘要：

目的 探讨无托槽隐形矫治中膜片厚度和牙齿唇向移位量对矫治力的影响,以期为临床提供参考.方法 设计右上中切牙唇向移位0.3、0.6、0.9、1.2、1.5和1.8 mm,三维打印2倍标准（牙合）模型大小的上颌树脂模型,并采用0.8、1.0、1.5和2.0 mm厚度的膜片压制无托槽隐形矫治器（每种移位量每种厚度制备6个）.利用无托槽隐形矫治微型测力系统测量矫治力.结果 相同牙齿移位量条件下,随着膜片厚度增加,矫治器产生的矫治力逐渐增大（P＜0.05）;唇向移位0.3 mm,0.8、1.0、1.5、2.0 mm厚度膜片产生的矫治力分别为（1.237±0.082）、（1.543±0.059）、（3.602±0.102）、（6.734±0.063）N.相同膜片厚度条件下,随着牙齿唇向移位量增加,矫治器产生的矫治力呈增加趋势（P＜0.05）;0.8mm厚度膜片,切牙唇向移位0.6、0.9、1.2、1.5mm时,矫治力分别为（1.354±0.039）、（1.288±0.037）、（1.479±0.031）、（1.799±0.039）N.结论 随着牙齿唇向移位量和膜片厚度的增加,无托槽隐形矫治器产生的矫治力相应增加.

英文摘要：

Objective To measure the orthodontic forces exerted on the upper right central incisor with the increase of the distance of tooth movement and the thickness of the aligner.Methods The labial movement of upper right central incisor at various distances （0.3,0.6,0.9,1.2,1.5,1.8 mm） was designed and the stereolithography model （2 times bigger than the original model） was created with 3-D scanning and tomography output.These models were used to fabricate the aligners with different thicknesses （0.8,1.0,1.5 and 2.0 mm） of the thermoplastic materials （6 samples for various distances of tooth movement and thicknesses）.Orthodontic forces exerted on the upper right central incisor were measured with the micro-stress sensor measurement system.Results The orthodontic forces increased with the increase of the thickness of the aligner at the same distance of tooth movement （P ＜ 0.05）.The orthodontic force was （1.237 ± 0.082）,（1.543 ± 0.059）,（3.602 ± 0.102）,（6.734 ± 0.063） N when the labial movement of upper right central incisor was 0.3 mm with the aligner of 0.8,1.0,1.5,2.0 mm.The orthodontic forces also increased with the increase of the distance of the tooth movement at the same thickness of the aligner （P ＜ 0.05）.The orthodontic force of the aligner of 0.8 mm were （1.354 ± 0.039）,（1.288 ± 0.037）,（1.479 ± 0.031）,（1.799 ± 0.039） N when the upper right central tooth labial movement at 0.6,0.9,1.2,1.5 mm.Conclusions The orthodontic forces increased with the increase of the distance of tooth movement and the thickness of the aligner.