【摘要】 目的:分析不同牙尖斜度对种植体支持全瓷单冠应力分布的影响。方法:利用COSMOS 2.85参照相关文献建立5个种植体支持的下颌第一磨牙全瓷单冠三维有限元模型,全瓷冠的颊尖斜度分别设计为20°、25°、30°、35°和40°,采用垂直和水平两种加载方式,分析不同牙尖斜度对全瓷冠、基台、种植体以及周围骨组织内部的应力影响。结果:全瓷冠内部的张应力和等效应力主要集中在全瓷冠颊侧颈部,压应力主要集中在全瓷冠表面加载部位。最大张应力在垂直加载下随牙尖斜度增加而增加,水平加载下随牙尖斜度增加而减小;最大压应力和等效应力在牙尖斜度为25°时最小。基台内部的应力主要集中在种植体-基台衔接处的颊侧;种植体应力集中部位在颈部颊侧;骨组织应力集中部位在种植体颈部皮质骨,垂直加载时在颊侧,水平加载时在颊舌侧。不同牙尖斜度时基台、种植体及骨组织内部的最大等效应力在垂直加载时无明显差异,在水平加载时随牙尖斜度的增加而增大。结论:不同牙尖斜度时种植体支持全瓷单冠的应力集中部位相似,最大应力与加载方式有密切关系。更多还原

【Abstract】 Objective:To analyze the influence of cusp inclination on the stress of implant supported all-ceramic single crown.Materials and Method:5 three-dimensional finite element models of implant supported all-ceramic crown for the first mandibular molar with different cusp inclination were established by COSMOS 2.85.The inclination of buccal cusp was 20,25,30,35 and 40 degrees respectively.Vertical and horizontal loading was applied to analyze the influence of cusp inclination on the stress within all-ceramic crown,abutment,implant and surrounding bone.Result:Within all-ceramic crown,the tensile and Von Mises stress concentrated at the buccal cervical marginal area,the compress stress concentrated at the loading position.The maximum tensile stress was increased as the cusp inclination increased under vertical loading,but decreased under horizontal loading.The maximum compress stress and Von Mises stress was lowest when the cusp inclination was 25 degrees.Within abutment and fixture,the stress concentrated at cervical part on buccal side.For surrounding bone,the stress concentrated at the cervical part on the buccal side under vertical loading and both buccal and lingual side under horizontal loading.Maximum stresses within the abutment,fixture and surrounding bone had no significant difference under vertical loading but increased as the cusp inclination increased under horizontal loading.Conclusion:The stress distribution of implant supported all-ceramic single crown was similar with different cusp inclinations.Maximum stresses were significantly influenced by the loading condition.更多还原