Influence of model discretization density in FEM numerical analysis on the determined stress level in bone surrounding dental implants

Abstract

Influence of mesh density on the results of FEM model analysis of mechanical biocompatibility of dental implants has not been presented yet. Taking advantage of the Ansys v.11 software, carried out was an analysis in the linear elastic range level of stresses in bone tissue surrounding standard osseointegrated implant of complete denture, with a decreasing size of elements (the tragonal type SOLID 187) adjacent to cortical bone/implant interface, respectively 0.5, 0.3 and 0.1. Equivalent Huber-Mises' stress value in the zone that is exposed to effort the most, and is located close to the edge of implant insertion into the cortex bone significantly increases along with mesh density from app. 60 MPa to 120 MPa for opposite models, because of the lack of convergence of stresses at this singularity point. Increase of mesh density leads to an overestimation of loading stresses values and furthermore to an unjustified increase of pillars' diameter. At the other hand, too large elements might lead, through an underestimation of loading stress level, to overloading atrophy of bone tissue or to implant loss. © 2008 Springer-Verlag Berlin Heidelberg.