de Matos Jefferson David Melo, Lopes Guilherme da Rocha Scalzer, Nakano Leonardo Jiro Nomura, Ramos Nathália de Carvalho, Vasconcelos John Eversong Lucena de, Bottino Marco Antonio, Tribst João Paulo Mendes
Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), Sao Paulo, Brazil.
Department of Dentistry, Universidade São Francisco (USF), Bragança Paulista, Brazil.
Comput Methods Biomech Biomed Engin. 2022 Feb;25(3):239-246. doi: 10.1080/10255842.2021.1946798. Epub 2021 Sep 24.
This study aimed to evaluate the biomechanical behavior, stress distributions and bone microstrain of fixed partial dentures (FPD) with ceramic abutments supported on monotype zirconia implants, titanium implants and two-piece zirconia implants, using finite element analysis. A three-dimensional model of the jaw was simulated containing 1.0 mm thick cortical bone and cancellous bone tissue. A FPD and implant models (4.1 x 10 mm) were modeled containing a cement-retained implant abutment. These models were replicated in three groups with similar geometries: Titanium Implant and Zirconia Abutment (Ti-Zr); Zirconia Implant and Zirconia Abutment (Zr-Zr) and Monotype Zirconia Implant (Zr-S). An axial load of 300 N was applied to the center of the first premolar. The microstrain (με) and the Von-Mises stress (MPa) were assumed as failures criteria. For the three groups, a higher stress concentration was observed in the region of FPD connectors. The Ti-Zr group showed a higher stress concentration in the prosthesis and implant when compared to the other groups. However, the smaller elastic modulus of the titanium implant, in relation to the zirconia, provided a lower stress in the abutment and in the prosthetic screw. The monotype implant system allowed a more homogeneous stress distribution and its strain were predominantly located in the cervical region of the peri-implant bone tissue. Monotype or two-piece zirconia implants can be used for rehabilitation with FPD. However, the absence of separation between implant and abutment in the monotype system avoids the stress concentration in the prosthetic screw and reduced the peri-implant bone strain.
本研究旨在通过有限元分析评估单型氧化锆种植体、钛种植体和两件式氧化锆种植体支持的陶瓷基台固定局部义齿（FPD）的生物力学行为、应力分布和骨微应变。模拟了包含1.0毫米厚皮质骨和松质骨组织的颌骨三维模型。构建了包含粘结固位种植体基台的FPD和种植体模型（4.1×10毫米）。这些模型被复制为三组，具有相似的几何形状：钛种植体和氧化锆基台（Ti-Zr）；氧化锆种植体和氧化锆基台（Zr-Zr）以及单型氧化锆种植体（Zr-S）。在第一前磨牙的中心施加300 N的轴向载荷。将微应变（με）和冯·米塞斯应力（MPa）作为失效标准。对于这三组，在FPD连接体区域观察到更高的应力集中。与其他组相比，Ti-Zr组在修复体和种植体中表现出更高的应力集中。然而，与氧化锆相比，钛种植体较小的弹性模量在基台和修复体螺钉中产生了较低的应力。单型种植体系统允许更均匀的应力分布，其应变主要位于种植体周围骨组织的颈部区域。单型或两件式氧化锆种植体可用于FPD修复。然而，单型系统中种植体和基台之间不存在分离，避免了修复体螺钉中的应力集中，并降低了种植体周围骨应变。
