Stress Distribution in All-Ceramic Posterior 4-Unit Fixed Dental Prostheses Supported in Different Ways: Finite Element Analysis

Introduction: The purpose of this finite element analysis (FEA) was to complement results of previously published studies that investigated the influence of abutment resilience on the load-bearing capacity of zirconia posterior 4-unit fixed dental prostheses (FDPs) with static load tests. Materials and Methods: Duplicates of 3 different physical specimens were modeled for FEA. The first virtual specimen was supported by teeth with periodontal resilience, the second by the combination of tooth and implant, and the third by implants only. The center of the FDP was loaded, vertically to the occlusal plane. The highest maximum principal stresses (MPSs) were computed. Discussion: The highest MPS in each model occurred in the basal region of the middle framework connector. Comparison between the 3 models showed that the tensile stresses were lower when the support of the FDP was more rigid. Numerically determined highest MPSs in the FDPs correlated well with experimentally observed load-bearing capacities. Conclusion: The FEA is well suited to confirm the in vitro study mentioned and complement the results with stress distributions in all-ceramic posterior 4-unit FDP.