Three-dimensional finite element analyses of all-ceramic posterior fixed partial dentures with different designs.

The aim was to evaluate the influence on the stress distribution patterns in and the magnitude of stresses on fixed partial dentures (FPDs) under different anatomic and design conditions. Three-dimensional finite element models of posterior 3-unit all-ceramic FPDs were created with and without periodontal ligaments, with different radii of curvature at the embrasure area, and in a curve shape with a periodontal ligament. The model with a periodontal ligament showed 40% higher stress values compared to the no-ligament model. A smaller radius of curvature resulted in 20% to 40% higher stress values. The curved model increased stress values at the distal connector by 65% compared to the straight model. Support by teeth, occlusal curvature, and a small radius of curvature at the embrasure area negatively affect stress distribution patterns in the connector area of all-ceramic FPDs.