Department of Endodontics, University of Chieti G. D'Annunzio, School of dentistry, Roma, Italy.
Med Oral Patol Oral Cir Bucal. 2011 Sep 1;16(6):e852-6. doi: 10.4317/medoral.17243.
To evaluate the biomechanical scenario of platform switching geometric implant-abutment configuration relative to standard configurations by means of finite element analysis.
A 3D Finite Element Analysis (FEA) was performed on 3 different implant-abutment configurations: a 3.8 mm implant with a matching diameter abutment (Standard Control Design, SCD), a 5.5 mm implant with matching diameter abutment (Wider Control Design, WCD), and a 5.5mm implant with a 3.8 mm abutment (Experimental Design, ED). All the different experimental groups were discretized to over 60000 elements and 100000 nodes, and 130N vertical (axial) and 90N horizontal loads were applied on the coronal portion of the abutment. Von Mises stresses were evaluated and maximum and minimum values were acquired for each implant-abutment configuration.
The load-induced Von Mises stress (maximum to minumum ranges) on the implant ranged from 150 MPa to 58 Pa (SCD); 45 MPa to 55 Pa (WCD); 190 MPa to 64 Pa (ED). The Von Mises stress on the abutment ranged from 150 MPa to 52 MPa (SCD); 70 MPa to 55 MPa (WCD), and 85 MPa to 42 MPa respectively (ED). The maximum stresses transmitted from the implant-abutment system to the cortical and trabecular bone were 67 Pa and 52 MPa (SCD); 54 Pa and 27 MPa (WCD); 64 Pa and 42 MPa (ED), respectively. When the implant body was evaluated for stresses, a substantial decrease in their levels were observed at the threaded implant region due to the diametral mismatch between implant and abutment for the ED configuration.
The platform switching configuration led to not only to a relative decrease in stress levels compared to narrow and wide standard configurations, but also to a notable stress field shift from bone towards the implant system, potentially resulting in lower crestal bone overloading.
通过有限元分析评估平台转换几何种植体-基台配置相对于标准配置的生物力学情况。
对 3 种不同的种植体-基台配置进行了 3D 有限元分析（FEA）：直径匹配的 3.8mm 种植体（标准对照设计，SCD）、直径匹配的 5.5mm 种植体（宽控制设计，WCD）和 5.5mm 种植体配 3.8mm 基台（实验设计，ED）。所有不同的实验组都被离散化到超过 60000 个元素和 100000 个节点，并在基台的冠部施加 130N 垂直（轴向）和 90N 水平载荷。评估了 Von Mises 应力，并获得了每种种植体-基台配置的最大和最小值。
种植体上的载荷诱导 Von Mises 应力（最大值到最小值范围）为 150MPa 至 58Pa（SCD）；45MPa 至 55Pa（WCD）；190MPa 至 64Pa（ED）。基台上的 Von Mises 应力为 150MPa 至 52MPa（SCD）；70MPa 至 55MPa（WCD），85MPa 至 42MPa（ED）。从种植体-基台系统传递到皮质骨和松质骨的最大应力分别为 67Pa 和 52MPa（SCD）；54Pa 和 27MPa（WCD）；64Pa 和 42MPa（ED）。当评估种植体体部的应力时，由于 ED 配置中种植体和基台之间的直径不匹配，在螺纹种植体区域观察到其水平显著降低。
与狭窄和宽标准配置相比，平台转换配置不仅导致应力水平相对降低，而且还导致应力场从骨向种植体系统显著转移，潜在导致牙槽骨过度负荷。
