biomechanical effects of platform switching in two different implant systems: a three-dimensional finite element analysis

Aims: The purpose of this study was to determine the influence of platform switching on stress distribution of two different implant systems, using three-dimensional (3D) finite element models.Methods: Six 3D finite element models were created to replicate two different implant systems with peri-implant bone tissue, in which six different implant-abutment configurations were represented: model XiVE-a: 3.8-mm-diameter implant and 3.8-mm-diameter abutment; model XiVE-b (platform-switching model): 4.5-mm-diameter implant and 3.8-mm-diameter abutment; model XiVE-c: 4.5-mm-diameter implant and 4.5-mm-diameter abutment; model 3i-a: 4.0-mm-diameter implant and 4.1-mm-diameter abutment; model 3i-b (platform-switching model): 5.0-mm-diameter implant and 4.1-mm-diameter abutment; model 3i-c: 5.0-mm-diameter implant and 5.0-mm-diameter abutment. Axial and oblique loads of 100 were applied to all models.Results: While the pattern of stress distribution was similar for both loading situations, oblique loading resulted in higher intensity and greater distribution of stress than axial loading in both cortical bone and abutment-implant interface. Stress distribution at peri-implant bone was almost identical with similar magnitudes for all six models. In both implant systems, platform switching models demonstrated lower maximum von Mises stress in cortical bone than conventional models. However, in both implant systems and under both loading situation, platform switching models showed higher stresses at the abutment-implant interface than conventional models.Conclusion: In both implant systems, platform switching design reduced the stress concentration in the crestal bone and shifted it towards the area of implant-abutment interface