Comparison of Stress Distribution in MOD Premolars Restored with Two Low Shrinkage Resin Composites Using Finite Element Analysis

The incremental filling technique in traditional resin composites results in reduced polymerization shrinkage. However, many products have recently been introduced as low-shrinkage resin composites that make the bulk-filling of cavities possible.

Three identical dental models from a premolar tooth were made using a CADCAM digital scanner in the solid work software environment. MOD cavities were designed and filled by Tetric EvoCeram® Bulk Fill, GC KALORE™, and 3M ESPE Filtek P60 (control group) resin composites. Incremental and bulk-fill techniques were used for Tetric EvoCeram® Bulk Fill while GC KALORE™, and 3M ESPE Filtek P60 resin composites were used with incremental technique in Ansys 16 simulation software environment. Stress distribution and cuspal deflection rate were analyzed in Ansys 16 software by Kruskal–Wallis and Mann-Whitney U tests.

The mean stress intensity for Tetric EvoCeram® Bulk Fill in the bulk-fill technique was more than the incremental technique. Cuspal deflection rate and stress distribution among the resin composites, GC KALORE™, Tetric EvoCeram® Bulk Fill, and 3M ESPE Filtek P60 were in ascending order, respectively. Stress distribution was more uniform in the incremental technique.

The GC KALORE™ resin composite had the least stress distribution and cuspal deflection rate.