Investigation of influence of different implant size and placement on stress distribution with 3-dimensional finite element analysis.

Abstract

The purpose of this study was to analyze the biomechanical behavior of implants with varying number, inclination, and size, using 3-dimensional finite element (FE) analysis. A total of 10 FE models were constructed to simulate 5 implant placement configurations: 4 and 5 axial implants, 4 implants inclined with 17.5 degrees mesial and 35 degrees distal, and 2 axial and 2 distal implants inclined with 17.5 and 35 degrees, using implants of 3.5 and 5.5 mm diameters. A vertical load of 300 N was applied to the distal portion of a standardized size metal framework. Increasing the number of implants decreased the stress in the bone for axially placed implant models. The short implants with a large diameter resulted in lower stress values in the bone, but higher stresses in the implant/abutment assembly than the long implants with a small diameter. Increasing diameter of implants decreased high stress concentration in the cortical bone, resulting from increasing cantilever length. Decreasing cantilever length with distal implant inclination decreases the stress values in the implant, cortical bone, and framework.