Stress distribution around implants with abutments of different materials: A comparison of photoelastic, strain gage and finite element analyses

Abstract

Objective: To compare stress transmission around implants with abutments made of three different materials using photoelastic, strain gage (SGA) and finite element (FEA) analyses. Methods: Three abutments - UCLA calcinable, cast in Ni-Cr; UCLA calcinable with a Cr-Co cervical collar, overcast with Ni-Cr; and a zirconia abutment - were installed on implants embedded in photoelastic resin. Vertical and oblique loads were applied to the abutments to the photoelastic and SGA analyses. Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (a=0.05). The assembly was modeled to FEA simulation. Results: Similar fringe orders were observed in the apical region under vertical load. The greatest fringe orders were observed in the coronal region of the opposite side of load application (contralateral side) under oblique load. By SGA, no statistical difference was observed among the abutments (P=0.061) under vertical load, and no difference was found between tensile and compression sides under oblique load. FEA showed no difference in stress distribution. The oblique load generated the greatest stress values on the contralateral side in the coronal area. Conclusion: Although it was not possible to establish an agreement among the analytical methods tested, different abutment materials did not influence the transmission of stresses around implants. Copyright: