Influence of prosthesis material on stress distribution in bone and implant: a 3-dimensional finite element analysis.

A 3-dimensional finite element analysis was conducted to assess stress distribution in bone, implant, and abutment when gold alloy, porcelain, or resin (acrylic or composite) was used for a 3-unit prosthesis. A unit force was applied axially and then buccolingually to the center of the pontic. For gold and porcelain, similar maximum equivalent stress was found in each part of the models. In almost all cases, stress in the model with the resin prostheses was similar to or higher than that in the models with the other 2 prosthesis materials. The highest increase in stress with the resins was found in the implant-abutment unit under axial load. The protective role of resin for the implant-bone interface could not be demonstrated under the conditions of this analysis.