A Comparison of Three- Dimensional Finite Element Stress Analysis with In Vitro Strain Gauge Measurements on Dental Implants

Purpose: The purpose of this study was to evaluate the compatibility of three-dimensional finite element stress analysis and in vitro strain gauge analysis in the measurement of strains on a dental implant. Materials and Methods: Two vertically placed implants embedded in a poly(methyl methacrylate) model were used. Strain gauges were bonded to the cervical parts of the implants, and seven cement-retained fixed partial dentures were fabricated. A three-dimensional model of the strain gauge analysis model was constructed, and an additional model in which human bone simulation was provided was also constructed. A static vertical load of 50 N was applied at certain locations to simulate centrally positioned axial and laterally positioned axial loading for strain gauge analysis and three-dimensional finite element stress analysis. Results: Statistically significant increases in strain levels were recorded between loading types in the strain gauge analysis (P .05). Strains obtained from strain gauge analysis were higher than for three-dimensional finite element stress analysis. There was a remarkable difference between the two finite element models under the conditions of laterally positioned axial loading. Conclusion: There are differences regarding the quantification of strains between strain gauge analysis and three-dimensional finite element stress analysis. However, there is a mutual agreement and compatibility between three-dimensional finite element stress analysis and in vitro strain gauge analysis on the determination of the quality of induced strains under applied load.