摘要
目的设计一种具有多孔和支撑结构的个性化钛下颌修复体,通过有限元分析其应力分布特征,评估修复体的临床应用价值及应用前景。方法拔除比格犬右侧下颌第4前磨牙及磨牙,愈合3个月后拍摄螺旋CT并建立下颌三维模型,模拟手术过程切除3 cm下颌骨并用个性化修复体重建,该修复体由基牙、支柱、实体单元、多孔单元及固位单元组成。建立个性化钛下颌修复体有限元模型A,分析负荷时修复体的峰值应力,当构成假体每部分的最大应力均小于其材料的屈服强度时进行下一步研究;构建假体、下颌骨以及螺钉装配完成的有限元模型B,加载咀嚼力,记录下颌骨的应力、应变及位移分布。结果当基牙垂直加载载荷100 N时,修复体实体、多孔结构的峰值应力分别为147.03、75.36 MPa,均小于其材料的屈服强度;皮质骨、松质骨的峰值应力分别为53.713、4.216 7 MPa,应变分别为3.753 6、3.562 5;修复体最大位移338.3μm。结论以犬下颌骨为例,通过有限元分析表明,设计的具有多孔和支撑结构的个性化修复体应力分布均匀,具有较好的力学性能。研究结果为修复下颌骨缺损的假体设计提供了一种新方法。
Objective To design a personalized titanium mandibular prosthesis with porous and support structure,and analyze its stress distribution characteristics through finite element analysis,so as to evaluate clinical value and prospect of the prosthesis. Methods The fourth mandibular premolar and molar from the right mandible of Beagle dogs were removed. The spiral CT was taken after three-month healing,and the three-dimensional( 3D)model of the mandible was established. Resection of 3 cm mandible with simulated surgical procedure and reconstruction with personalized restoration were conducted. The prosthesis consisted of abutment,pillar,solid unit,porous unit and retention unit. A personalized titanium mandibular prosthesis finite element model A was established,to analyze the prosthesis stress under loading,and further study was proceeded when the maximum stress of each part constituting the prosthesis was smaller than yield strength of its material. The finite element model B with the assembly of the prosthesis, mandible and screw was constructed and loaded with the mastication force,and the stress,strain and displacement distributions of the mandible were recorded. Results When the abutment was under 100 N vertical loading,the peak stress of the prosthesis with solid structure and porous structure was 147. 03 and 75. 36 MPa,respectively,which was smaller than yield strength of its material;the peak stress of the cortical bone and cancellous bone was 53. 713,4. 216 7 MPa,and the strain was 3. 753 6,3. 562 5,respectively;the maximum displacement of the restoration was 338. 3 μm. Conclusions Taking the canine mandible as an example,the personalized prosthesis with porous and support structure shows the uniform stress distribution and good mechanical properties through finite element analysis. The results provide a new method for the design of prosthesis for repairing mandibular defects.
作者
郭芳
黄硕
刘宁
薛洋
胡敏
刘昌奎
GUO Fang;HUANG Shuo;LIU Ning;XUE Yang;HU Min;LIU Changkui(College of Stomatology,Xi'an Medical University,Xi'an 710021,China;College of Stomatology the Air Force Military Medical University,Xi'an 710032,China;Department of Oral and Maxillofacial Surgery,General Hospital of PLA,Beijing 100853,China)
出处
《医用生物力学》
CAS
CSCD
北大核心
2021年第5期776-782,共7页
Journal of Medical Biomechanics
基金
国家自然科学基金项目(81801034)
陕西省西安市未央区科技计划项目(201929)
西安医学院高层次人才引进基金项目(2018RCYJ03)。
关键词
下颌骨缺损
修复体重建
多孔结构
有限元分析
力学性能
mandibular defects
restoration reconstruction
porous structure
finite element analysis
mechanical properties
