Tribst João Paulo Mendes, de Morais Dayana Campanelli, Alonso Alexandre Abhdala, Piva Amanda Maria de Oliveira Dal, Borges Alexandre Luis Souto
Department of Dental Materials and Prosthodontics, São Paulo University, São Paulo, Brazil.
J Indian Prosthodont Soc. 2017 Jul-Sep;17(3):255-260. doi: 10.4103/jips.jips_11_17.
The increase of requests for implant-supported prosthesis (ISP) with zirconia as infrastructure has attracted a lot of attention due to its esthetics, biocompatibility, and survival rate similar to metallic infrastructure. The aim of this study was to evaluate the influence of two different framework materials on stress distribution over a bone tissue-simulating material.
Two ISP were modeled and divided into two infrastructure materials: titanium (Ti) and zirconia. Then, these bars were attached to a modeled jaw with polyurethane properties to simulate bone tissue. An axial load of 200 N was applied on a standardized area for both systems. Maximum principal stress (MPS) on solids and microstrain (MS) generated through the jaw were analyzed by finite element analysis.
According to MS, both models showed strains on peri-implant region of the penultimate (same side of the load application) and central implants. For MPS, more stress concentration was slightly higher in the left posterior region for Ti's bar. In prosthetic fixation screws, the MPS prevailed strongly in Ti protocol, while for zirconia's bar, the cervical of the penultimate implant was the one that highlighted larger areas of possible damages.
The stress generated in all constituents of the system was not significantly influenced by the framework's material. This allows suggesting that in cases without components, the use of a framework in zirconia has biomechanical behavior similar to that of a Ti bar.
以氧化锆为基础结构的种植体支持式修复体（ISP）需求的增加因其美学效果、生物相容性以及与金属基础结构相似的生存率而备受关注。本研究的目的是评估两种不同框架材料对骨组织模拟材料上应力分布的影响。
制作两个ISP模型，并分为两种基础结构材料：钛（Ti）和氧化锆。然后，将这些杆连接到具有聚氨酯特性的模拟颌骨上以模拟骨组织。对两个系统在标准化区域施加200 N的轴向载荷。通过有限元分析对固体上的最大主应力（MPS）和通过颌骨产生的微应变（MS）进行分析。
根据MS，两个模型在倒数第二颗种植体（与载荷施加在同一侧）和中央种植体的种植体周围区域均显示出应变。对于MPS，Ti杆在左后区域的应力集中略高。在修复固定螺钉中，MPS在Ti方案中占主导地位，而对于氧化锆杆，倒数第二颗种植体的颈部是突出显示可能损伤较大区域的部位。
系统所有组成部分产生的应力不受框架材料的显著影响。这表明在没有组件的情况下，使用氧化锆框架具有与Ti杆相似的生物力学行为。
