青少年安氏Ⅱ类错牙合畸形戴用AdvanSync功能矫治器时颞下颌关节应力分布有限元分析

摘要

Objective Three dimensional finite element method analysis is used in stress analysis of the temporomandibular joint in patient under treatment of junior classⅡmalocclusion with AdvanSync appliance to explore whether the temporomandibular joint has adaptive remodeling under localized stimulus.Methods An 11-year-old classⅡDivision 1 malocclusion patient was selected as a volunteer in this research.CBCT was used in scanning the head of the patient.And the data was output as graphic data, which was established into three-dimensional finite element model of appliances maxilla mandible and dentition by mimics17.0 software.ANSYS workbench 15.0 software was used in three-dimensional model boundary and loading force valued 5.7 N, and making the stress analysis of the temporomandibular joint.Results Three-dimensional model of AdvanSync functional appliances was established.When the app-liance was leaded force,the left side and the right side of the temporomandibular joint stress distribution were basically the same.Equivalent stress mainly concentrated in front of the condylar slope near the neck of condyle, condylar cartilage,, and articular disc cavity.The maximum principal stress distribution of equivalent stress analysis results were basically the same, mainly bear tensile force;the minimum principal stress mainly concentrated on the top of condyle and condylar cartilage at the top, which is mainly bear compressive stress.Conclusion When AdvanSync functional appliance leads submaxila forward, condylar process and condylar chondrocyte have the adaptive trend under pressure.But articular disc and fossa have little effect.%目的 运用三维有限元法分析AdvanSync矫治器在治疗安氏Ⅱ类青少年错牙合畸形时颞下颌关节的应力分布,探讨颞下颌关节能否在局部刺激作用下发生适应性改建.方法 选择一名11岁男性的安氏Ⅱ类1分类错牙合畸形患者为研究志愿者,对其头部行CBCT扫描,通过mimics17等软件建立包含功能矫治器、上颌骨、下颌骨及牙列的3种颌位关系的有限元模型.运用Ansys workbench 15软件对有限元模型进行边界约束,对功能矫治器加载5.7 N的载荷力并进行应力数据分析,观察颞下颌关节应力分布情况.结果 建立含有AdvanSync功能矫治器的三维模型;当功能矫治器承受加载力时,颞下颌关节左右侧应力分布基本一致,3种颌位应力值略有差别,应力变化主要表现在髁突.最大主应力集中在髁突颈部、髁突软骨前部,关节盘上腔前带;最小主应力主要集中在髁突顶部,髁突软骨顶部.结论 AdvanSync功能矫治器前导下颌时,髁突及髁突软骨受应力的良性刺激是关节发生适应性改建的基础;关节盘与关节窝受应力影响较小.