Manzella Carlo, Bignardi Cristina, Burello Valerio, Carossa Stefano, Schierano Gianmario
Tutor, Surgical Science Department, Prosthodontic Section, Dental School C.I.R, University of Turin, Italy.
Associate Professor, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy.
J Prosthet Dent. 2016 Jul;116(1):52-8. doi: 10.1016/j.prosdent.2016.01.006. Epub 2016 Mar 2.
The passivity of the superstructure to the abutments of implant-supported prostheses is necessary for implant-prosthesis success. Improvements are needed in the methods of verifying passivity.
The purpose of this in vitro study was to evaluate an inexpensive, easy to make, and user-friendly device to verify the position of the implant abutment replicas of the definitive cast and to avoid framework misfit before fabrication.
Eighty stone devices were constructed on a metal base for the in vitro tests. The horizontal, vertical, and angled positions of the implant replicas were created to simulate misfits. The devices were fitted on the abutment replicas, and their ability to identify misfits was evaluated. A statistical analysis was not indicated, because the probability of fracture of the stone devices was 0 or 1. Two mathematical models were built using computer-aided design software (SolidWorks Premium; Dassault Systèmes SolidWorks Corp), and the finite element method was used (Ansys; ANSYS Inc) to simulate the structural behavior of 2 implant configurations (4 and 6 implants).
Horizontal misfits of 150 μm, vertical misfits of 50 μm, and angled misfits of 1 degree were detected during the in vitro tests. Different loads and bone quality in the mathematical models did not change stress in the prosthesis configurations on 4 or 6 implants in a relevant way.
The fabricated device was easily able to detect the misfits in accordance with the defined parameters.
种植体支持式修复体上部结构与基台之间的被动性对于种植修复的成功至关重要。在验证被动性的方法方面仍需改进。
本体外研究的目的是评估一种价格低廉、易于制作且用户友好的装置，用于验证最终模型上种植体基台复制体的位置，并在制作前避免支架不贴合。
制作了80个用于体外测试的石质装置，其金属底座上。通过设置种植体复制体的水平、垂直和倾斜位置来模拟不贴合情况。将这些装置安装在基台复制体上，评估其识别不贴合情况的能力。由于石质装置断裂的概率为0或1，因此未进行统计分析。使用计算机辅助设计软件（SolidWorks Premium；达索系统SolidWorks公司）构建了两个数学模型，并采用有限元方法（Ansys；ANSYS公司）模拟了两种种植体配置（4颗和6颗种植体）的结构行为。
体外测试中检测到水平不贴合150μm、垂直不贴合50μm和倾斜不贴合1度。数学模型中不同的载荷和骨质量并未以显著方式改变4颗或6颗种植体的修复体配置中的应力。
所制作的装置能够轻松地根据定义的参数检测到不贴合情况。
