Comparison of finite element and photoelastic stress analysis methods

Objectives: The aim of this study was to compare finite element (FEM) and photoelastic stress (PM) analysis methods. Methods: Mandibular section of bone with a missing second premolar tooth and an implant to receive a crown was developed. A solid 4.1 × 10-mm screw-type dental implant system (ITI; solid implant) and a metal-ceramic crown using Co-Cr (Wiron 99) and feldspathic porcelain and IPS Empress 2 crown designs were modeled. A load of 300 N was applied in a vertical direction to the buccal cusp of the crowns. FEM and PM were used for evaluation of stress distribution. Results:When the stress values and distributions on implant and cortical bone were evaluated using FEM , maximum stress was concentrated in the neck of implant and abutment. Maximum stress on supporting bone was concentrated at the level of cortical bone around the neck and apical region of the implant for each crown design. In PM, stress was located around the grooves and apex of the implant for each crown design. As a result of vertical loads, an equivalent amount of stress was observed in the bone in both porcelain fused to base metal (PFBM) and IPS Empress 2 crown designs. Conclusions: Both methods were gave information about stress distribution in supporting bone however more detailed information was obtained about the location, type and mathematical value of stresses using FEM.

This study is supported by Selcuk University Scientific Research Coordination (BAP)