Meyer Ulrich, Vollmer Dirk, Runte Christoph, Bourauel Christoph, Joos Ulrich
Department of Cranio-Maxillofacial Surgery, University of Münster, Germany
J Maxillofac Surg. 2001 Apr;29(2):100-105. doi: 10.1054/jcms.2001.0198.
Introduction: Oral implants placed in the maxilla, especially the posterior region, have a lower success rate than those placed in the mandible. Poor bone quantity and quality have been suggested as a reason for this differential success rate. Objective: The purpose of this study was, therefore, to evaluate stress and strain distributions around loaded implants in the normal and atrophic maxilla by finite-element (FE) analyses. Material: FE models of a solitary implant were generated to determine stresses and strains in the bone adjacent to the implant surface under loading conditions. Study design: Different bony situations and implant lengths were used in a FE model. Static loads were applied axially and the resulting stresses and strains calculated. Results: Bone quality and quantity play a major role in decreasing bone strains adjacent to the implant surface under loading. It was found that stresses were more homogeneously distributed when more spongy bone was present. Decreased bone height was found to have less pronounced effects on strain and stress alterations than poor bone quality. Atrophic bony dimensions in combination with poor bone quality were associated with surface strains exceeding physiological levels (>6000 microstrains). Conclusion: Our investigation indicates that supraphysiological bone strains adjacent to the implant surface should be expected under mechanical loading in the atrophic maxilla. Copyright 2001 European Association for Cranio-Maxillofacial Surgery.
植入上颌骨，尤其是上颌后部区域的口腔种植体，其成功率低于植入下颌骨的种植体。骨量和骨质量不佳被认为是导致这种成功率差异的一个原因。目的：因此，本研究的目的是通过有限元分析来评估正常和萎缩性上颌骨中加载种植体周围的应力和应变分布。材料：生成单个种植体的有限元模型，以确定加载条件下种植体表面相邻骨中的应力和应变。研究设计：有限元模型中使用了不同的骨情况和种植体长度。轴向施加静态载荷并计算由此产生的应力和应变。结果：骨质量和骨量在降低加载情况下种植体表面相邻骨的应变方面起主要作用。发现当存在更多松质骨时，应力分布更均匀。发现骨高度降低对应变和应力变化的影响不如骨质量差那么明显。萎缩性骨尺寸与骨质量差相结合会导致表面应变超过生理水平（>6000微应变）。结论：我们的研究表明，在萎缩性上颌骨的机械加载下，种植体表面相邻骨的应变应会超过生理水平。版权所有2001年欧洲颅颌面外科学会。
