不同厚度及刚性隐形矫治器内收上颌前牙的有限元分析  

Finite element analysis of internally retracted maxillary anterior teeth with clear aligners of different thicknesses and stiffness

作　　者：杨天梅 王婧[1] 马福娟 张俭[1] 葛振林[2] Yang Tianmei;Wang Jing;Ma Fujuan;Zhang Jian;Ge Zhenlin(Lanzhou University,Lanzhou 730000,Guansu Province,China;Department of Orthodontics,School of Stomatology,Lanzhou University,Lanzhou 730000,Guansu Province,China)

机构地区：[1]兰州大学,甘肃省兰州市730000 [2]兰州大学口腔医学院正畸科,甘肃省兰州市730000

出　　处：《中国组织工程研究》2025年第22期4671-4678,共8页Chinese Journal of Tissue Engineering Research

摘　　要：背景:隐形矫治器因其特殊的材料性能,在拔除上颌第一前磨牙内收前牙关闭间隙过程中更易发生“过山车效应”,牙齿倾斜移动,导致前牙覆牙合加深、后牙开牙合。是否可以通过改变矫治器厚度或刚性减轻“过山车效应”,更好地控制正畸牙移动,目前相关研究较少。目的:通过三维有限元分析不同厚度及刚性隐形矫治器内收上颌前牙时控制牙齿移动能力方面的差异。方法:将侧貌凸患者的锥形束CT数据导入Mimics等软件,模拟临床病例,构建去除第一前磨牙后包括上颌骨、牙齿、牙周膜的三维有限元模型,装配0.50,0.75 mm 2种厚度膜片的隐形矫治器,通过软件加载1000,2000 MPa 2种弹性模量的材料属性,总共构建4组模型工况。按照临床矫治方案设计关闭拔牙间隙,在Workbench 2023 R1软件中加载并计算,分析牙周膜应力分布、牙齿位移趋势及牙齿初始位移量。结果与结论:(1)4种模型工况下的牙周膜Von-Mises应力分布规律一致,牙周膜最大等效应力主要分布在牙颈部,并且矫治器膜片越厚牙周膜Von-Mises应力越大、矫治器膜片弹性模量越大牙周膜Von-Mises应力越大;(2)4种模型工况下的上颌牙列整体位移趋势为前牙冠舌向、根唇向的移动,后牙冠近中移动、根远中移动,牙齿的冠、根位移方向均相反,牙冠位移量大于牙根位移量;除尖牙外,其余牙齿均呈现矫治器膜片越厚R/C值(牙根移动量与冠移动量比值)越小、矫治器膜片弹性模量越大R/C值越小的趋势;(3)结果表明,利用隐形矫治器内收上颌前牙时,在不设计切牙转矩补偿的情况下牙齿表现为倾斜移动趋势,矫治器厚度和弹性模量越大时对牙齿控的制能力越强,牙齿倾斜移动趋势减小;尖牙则需通过其他辅助手段进行控制。BACKGROUND:Clear aligners,due to their special material properties,are more prone to the“roller coaster effect”during the process of extracting the maxillary first premolar and closing the gap by retracting the anterior teeth,tilting and moving the teeth,leading to deepening of the anterior overjet and opening of the posterior teeth.There are fewer related studies at present concerning whether the thickness or stiffness of the aligner can be changed to reduce the“roller coaster effect”and better control the orthodontic tooth movement,.OBJECTIVE:To analyze the differences in tooth movement control ability of clear aligners of different thicknesses and stiffness when internally retracting maxillary anterior teeth by means of the three-dimensional finite element method.METHODS:Cone beam CT data of patients with convex profile were imported into Mimics and other software to simulate clinical cases.Three-dimensional finite element models were constructed to remove the first premolars,including the maxilla,teeth,and periodontal ligaments,while the diaphragms of clear aligners with thicknesses of 0.50 mm and 0.75 mm were assembled.Four sets of working conditions were created by loading the material properties of two Young’s modulus of 1000 MPa and 2000 MPa.According to the clinical design to close of the extraction gap,and analyze the distribution of periodontal ligament stress,the displacement trend and the initial displacement of the teeth after loading and calculating in Workbench 2023 R1 software.RESULTS AND CONCLUSION:(1)The Von-Mises stress distribution pattern of periodontal ligament was consistent among the four working conditions,with the maximum value mainly distributed at the cervical part of teeth.The thicker diaphragm of the aligner,the higher the Von-Mises stress;the higher Young’s modulus of the aligner,the higher the Von-Mises stress.(2)Under the four working conditions,the overall displacement trend of the maxillary dentition was that the crowns of the anterior teeth moved towards the lingua

关 键 词：隐形矫治器 内收前牙 弹性模量 膜片厚度 有限元分析 生物力学 

分 类 号：R459.9[医药卫生—治疗学] R319[医药卫生—临床医学] R783.1