微型正畸装置形状记忆合金弓丝非线性止锁机制设计  

Design of nonlinear locking mechanism for shape memory alloy archwire of miniature orthodontic device

作　　者：代清源 吉利[2,3] 华嘉皓 梁振宇 余健文 陈太聪 DAI Qingyuan;JI Li;HUA Jiahao;LIANG Zhenyu;YU Jianwen;CHEN Taicong(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,P.R.China;The First Affiliated Hospital,Sun Yat-sen University,Guangzhou 510080,P.R.China;Guangzhou OO Stomatology Institute,Guangzhou 510080,P.R.China;Guangzhou OO Medical Scientific Limited,Guangzhou 510080,P.R.China;State Key Laboratory of Subtropical Building and Urban Science,Guangzhou 510640,P.R.China)

机构地区：[1]华南理工大学土木与交通学院,广州510640 [2]中山大学附属第一医院,广州510080 [3]广州欧欧口腔医疗研究院,广州510080 [4]广州欧欧医疗科技有限责任公司,广州510080 [5]亚热带建筑与城市科学国家重点实验室,广州510640

出　　处：《生物医学工程学杂志》2024年第4期766-774,共9页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(52178479);广州市创新创业领军人才项目(2021-L004);广东省现代土木工程技术重点实验室项目(2021B1212040003)。

摘　　要：目前研发的新型国产正畸装置中,托槽与形状记忆合金(SMA)弓丝之间的止锁机制是控制牙体精准矫正的关键。为满足临床治疗中的止锁力需求,止锁螺栓的紧固扭角及所需要的扭矩大小需要精准设计。为此,本文开展止锁机制的设计研究,分析紧固扭角与止锁力的对应关系,确定有效的扭矩值,其中涉及复杂耦合的接触、材料和几何非线性特征。首先,针对SMA弓丝的三点弯曲实验数据,开展基于参数正交实验设计的仿真分析,确定SMA超弹性材料参数。其次,建立螺栓旋紧和弓丝拉拔的两阶段精细有限元仿真模型,通过关键接触参数的优化设置,实现非线性分析收敛。最后,开展三种紧固扭角情况下的多组标定实验。本研究通过设计分析与标定实验的对比结果表明,各情况下止锁力的设计分析值与标定均值的偏差在10%以内,设计分析方法有效可靠。本研究最终确定临床应用的紧固扭角为10°,额定扭矩为2.8 N·mm。综上,本文所得关键数据可用于新型正畸装置的临床方案设计和后续机械优化,研究方法可为包含SMA材料的医疗器械受力分析提供有益参考。The locking mechanism between bracket and shape memory alloy(SMA)archwire in the newly developed domestic orthodontic device is the key to controlling the precise alignment of the teeth.To meet the demand of locking force in clinical treatment,the tightening torque angle of the locking bolt and the required torque magnitude need to be precisely designed.For this purpose,a design study of the locking mechanism is carried out to analyze the correspondence between the tightening torque angle and the locking force and to determine the effective torque value,which involves complex coupling of contact,material and geometric nonlinear characteristics.Firstly,a simulation analysis based on parametric orthogonal experimental design is carried out to determine the SMA hyperelastic material parameters for the experimental data of SMA archwire with three-point bending.Secondly,a two-stage fine finite-element simulation model for bolt tightening and archwire pulling is established,and the nonlinear analysis is converged through the optimization of key contact parameters.Finally,multiple sets of calibration experiments are carried out for three tightening torsion angles.The comparison results between the design analysis and the calibration experiments show that the deviation between the design analysis and the calibration mean value of the locking force in each case is within 10%,and the design analysis method is valid and reliable.The final tightening torque angle for clinical application is determined to be 10°and the rated torque is 2.8 N∙mm.The key data obtained can be used in the design of clinical protocols and subsequent mechanical optimization of novel orthodontic devices,and the research methodology can provide a valuable reference for force analysis of medical devices containing SMA materials.

关 键 词：正畸装置 止锁机制 形状记忆合金 正交实验设计 

分 类 号：R783.1[医药卫生—口腔医学]