Finite Element Analysis of Platform Switching Effects on Stress Distribution in Posterior Implants Placed in...

The present study was conducted to compare stress distribution in platform-switched and non-platform-switched implants placed in D2 (mandible) and D3 (maxilla) bones under axial and oblique loading, using finite element analysis (FEA).

Cone-beam computed tomography (CBCT)-derived three-dimensional models of the posterior maxilla (D3) and mandible (D2) were developed. Implants (11.5 × 4.2 mm) were modeled with two abutment configurations: 4.2 mm (non-platform switching) and 3.2 mm (platform switching). Porcelain-fused-to-metal crowns were placed on all models. A vertical (axial) load of 200 N and an oblique load of 200 N at 30° were applied to the left first molar. ANSYS Workbench (ANSYS, Inc., Canonsburg, Pennsylvania) was used to assess the von Mises stress distribution in the cortical bone, cancellous bone, implant, abutment, and abutment screws.

Platform switching resulted in lower stress values in both D2 and D3 bones under axial and oblique loads, especially at the crestal bone level. The D3 (maxillary) models exhibited higher stress concentrations overall than the D2 (mandibular) models, indicating a greater biomechanical challenge in less dense bone. Platform switching effectively reduced the peak stresses and led to a more uniform stress distribution. However, the implant and abutment components in the platform-switched models experienced higher internal stress.

Platform switching improved stress distribution and reduced crestal bone stress in both D2 and D3 bones, especially under oblique loading.