Influence of Different Angulations of Force in Stress Distribution in Implant Retained Finger Prosthesis: A Finite Element Study

Abstract

The success in implant retained finger prosthesis is determined by the implant loading and the characteristic of the force is a determining factor in implant loading. The stress distribution varies in finger bone when the loading forces are applied along the various angulations. Aim of this article is to evaluate stress distributions in finger bone when the loading forces are applied along the various angulations of force over the implant using finite element analysis. A finger bone model containing cortical bone and cancellous bone was constructed by using radiograph. Astratech Osssospeed bone level implant of 4.5 mm diameter and 14 mm length was selected for the study. The different angulations of force (0, 30, 60 and 90 degree) were applied to the implant abutment and the stresses generated where analyzed. Results showed when the force was applied at various angulations, the stress generated increased from 0 degree to 90 degree. The maximum stress (124.01 MPa) was at 90 degree force and minimum (31.67 MPa) was at 0 degree force. The maximum stresses were located around the neck of the implant and the cortex bone receives more stress than cancellous bone. So, to achieve long term success, the implant systems must confront biomaterial and biomechanical problems, including in vivo forces on implants, load transmission to the interface and prevent force along the long axis of the implant. Abbreviations: Finite element model (FEM), Finite Element Analysis (FEA), Newton (N), Mega Pascal (MPa), Computer Aided Design (CAD), 3D (3 Dimension).