Dos Santos Marsico Vívian, Lehmann Roberto Brunow, de Assis Claro Cristiane Aparecida, Amaral Marina, Vitti Rafael Pino, Neves Ana Christina Claro, da Silva Concilio Lais Regiane
Department of Prosthodontics, Dental School, University of Taubaté, Taubaté, SP, Brazil.
Department of Electrical Engineering, Dental School, Fluminense Federal University, Volta Redonda, RJ, Brazil.
Mater Sci Eng C Mater Biol Appl. 2017 Nov 1;80:141-148. doi: 10.1016/j.msec.2017.05.071. Epub 2017 May 16.
The aim of this study was to investigate the influence of occlusal splint therapy on the stress distribution of implant-supported fixed dental prosthesis (FDP) and peri-implantal bone structures using three-dimensional (3D) finite element analysis (FEA). The system consisted of two implants (positioned on region of second premolar and second molar) as retainers of fixed porcelain-fused-to-metal 3-unit FDP (first molar as pontic element). Two implant connections systems (external and internal hexagon) were tested. Static axial loads simulating functional (100N) and overloaded (300N) chewing were applied on the occlusal surface of the FDP covered or not with the occlusal splint. Maximum von Mises stress and bioperformance were accessed for the implants and bone tissues (cortical and cancellous) models. Analytic results indicated that independently of the load condition, implant region, and connection type, the presence of the occlusal splint decreased the stress developed in the implants. Both bone tissues showed increased levels of von Mises stress, and the bioperformance index was far from their maximum yield strength. The internal hexagon implants presented lower stress on premolar and molar regions than external hexagon implants under functional load and overload. The presence of the occlusal splint device over implant-supported FDP may be clinically useful for forwarding stresses towards the bone structure to maintain implants for long term.
本研究的目的是利用三维（3D）有限元分析（FEA），研究咬合板治疗对种植体支持的固定义齿（FDP）应力分布及种植体周围骨结构的影响。该系统由两颗种植体（位于第二前磨牙和第二磨牙区域）作为固定烤瓷熔附金属3单位FDP的固位体（第一磨牙作为桥体）组成。测试了两种种植体连接系统（外六角和内六角）。在覆盖或未覆盖咬合板的FDP咬合面上施加模拟功能性（100N）和过载（300N）咀嚼的静态轴向载荷。获取种植体和骨组织（皮质骨和松质骨）模型的最大冯·米塞斯应力和生物力学性能。分析结果表明，无论载荷条件、种植体区域和连接类型如何，咬合板的存在都会降低种植体中产生的应力。两种骨组织的冯·米塞斯应力水平均升高，且生物力学性能指标远未达到其最大屈服强度。在功能载荷和过载情况下，内六角种植体在前磨牙和磨牙区域的应力低于外六角种植体。在种植体支持的FDP上使用咬合板装置在临床上可能有助于将应力导向骨结构，以长期维持种植体。
