下颌双种植体支持的三种磁性覆盖义齿的生物力学有限元分析及结构优化设计

发布时间：2018-12-24 14:05

【摘要】：目的：两个种植体支持的下颌种植覆盖义齿能为无牙颌患者提供有效的修复方式,本研究的目的是通过三维有限元法对比分析下颌双种植体支持的三种不同类型的磁性覆盖义齿的生物力学特点,为优化下颌双种植体支持的磁性覆盖义齿的设计及临床修复提供理论依据。方法：本研究共建立三个不同的有限元模型,包含两个种植体支持的下颌种植磁性覆盖义齿,设计了平面型、圆顶型和衬垫型三种不同磁性附着体来支持覆盖义齿。对每个模型的覆盖义齿施加四种不同的加载力：100 N垂直向加载在下颌切牙、100 N垂直向加载在右下尖牙、100N垂直向及倾斜向(颊舌向倾斜450)加载在右下第一磨牙。记录并分析了种植体周围骨质、基台及粘膜上的应力特征。结果：在所有加载条件下,平面型磁性覆盖义齿修复时修复体组件及其支持组织上的应力比圆顶型及衬垫型大；磨牙倾斜加载时,显示的应力值为垂直向的三倍；此时粘膜的形变也是最明显,为其他加载条件下的三倍。结论：与平面型磁性附着体相比,圆顶型和衬垫型磁性附着体显示了更合理的应力／应变分布；对所有的种植磁性覆盖义齿而言,斜向力的危害最大,能造成种植体周围骨组织及附着体的应力集中,并且能破坏义齿的稳定性；这些结果表明：对于双种植体支持的下颌种植磁性覆盖义齿而言,圆顶型和衬垫型磁性附着体为更佳选择,特别是对骨质疏松或者骨质缺陷的患者而言。
[Abstract]:Objective: two implant-supported overdentures can provide an effective method for the restoration of edentulous patients. The purpose of this study was to compare and analyze the biomechanical characteristics of three different types of magnetic overdentures supported by two mandibular implants by using three-dimensional finite element method. It provides theoretical basis for optimizing the design and clinical restoration of magnetic overdenture supported by mandibular double implants. Methods: in this study, three different finite element models were established, including two implant-supported mandibular implants with magnetic overdentures. Three kinds of magnetic attachments were designed to support the overdentures: plane type, dome type and cushion type. Four different loading forces were applied to the overdenture of each model: 100 N vertical loading on the mandibular incisor, 100 N vertical loading on the right lower canine, and 100 N vertical and oblique (buccal and lingual tilt 450) loading on the lower right first molar. Stress characteristics of bone, base and mucosa around implants were recorded and analyzed. Results: under all the loading conditions, the stress of the prosthesis and its supporting tissue was larger than that of the dome and liner, and the stress value of the molars was three times that of the vertical. At this time, the deformation of mucous membrane is also the most obvious, which is three times as much as that under other loading conditions. Conclusion: compared with planar magnetic attachments, dome and liner magnetic attachments show more reasonable stress / strain distribution. For all implant-magnetic overdentures, the oblique force is the most harmful, which can cause stress concentration in the bone tissue and attachment around the implant, and destroy the stability of the denture. These results suggest that the domed and padded magnetic attachments are a better choice for mandibular implant-supported magnetic overdentures, especially for patients with osteoporosis or bone defects.
【学位授予单位】：复旦大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R783.6

【参考文献】