【摘要】 目的:探讨2个种植体进行无牙下颌覆盖义齿修复时,种植体位置、长度和基台高度对种植体及周围骨界面应力分布的影响。方法:建立无牙下颌覆盖义齿三维有限元模型。种植体垂直下颌骨植入。根据植入位点分别于第一前磨牙和侧切牙、长度分别为10mm、14mm和基台高度分别为2mm、6mm进行分组。模拟单侧咀嚼时最大受力情况,于义齿46牙合面中央窝施加300N垂直向力,1#记为加力侧种植体,2#为对侧种植体,对模型各部分进行应力分析。结果:种植体植入第一前磨牙位点与侧切牙位点相比较,下颌骨和2个种植体应力均明显增加,加力侧种植体增幅明显。同一位点种植体长度为14mm时,与10mm相比较,下颌骨应力小幅减小,种植体应力小幅增加。当同一位点种植体基台高度为6mm时,与2mm相比较,下颌骨和1#种植体应力明显增加,2#种植体的应力小幅减小。结论:从最大限度减小各部位应力角度考虑,单侧咀嚼力作用下,采用2个种植体进行无牙下颌覆盖义齿修复时,种植体植入侧切牙位点比第一前磨牙位点更有利;当植入位点相同时,增加种植体长度可小幅减小种植体周围骨组织应力,而种植体应力小幅增加;当基台高度减小,加力侧种植体和周围骨组织应力均明显减小。更多还原

【Abstract】 Objective: To explore the effects of implant position, length and abutment height on stress distribution of implant and its surrounding bone with three-dimensional finite element when two implants were used to support edentulous mandibular overdenture. Methods: Edentulous mandibular and two implants were established with CT images, based on implant position(lateral incisor or first premolar), length(10 mm or 14 mm) and abutment height(2 mm or 6 mm). The implants were named #1 and #2 from the loading point.A vertical 300 N was loaded at central fossa of right first molar. The Von Mises were analyzed. Results: 1) The stress of mandible and two implants exhibiting variable increasing when implants in first premolar position.1# stress increased significantly. 2) Compared with 10 mm, when implants length 14 mm, stress of mandible exhibiting minor reduction but implants stress exhibiting minor augment. 3) When abutments height 6 mm, compared with 2 mm, mandible and 1# stress increased significantly, 2# implant stress exhibiting minor reduction. Conclusions:Under present condition, implant placement of lateral incisor was better than first premolar, increasing implant length can slightly reduce stress of implants and surrounding bone, when abutment height decreased, and implants and mandible stress increased. Further clinical studies are needed.更多还原