Polymerization efficiency of bulk-fill dental resin composites with different curing modes

The aim of this study was to investigate the effect of four different curing modes on the polymerization efficiency of eight bulk-fill composites. Five specimens for each material were prepared for Vickers hardness measurements. The measurements were performed at 0 and 2 or 4 mm from the top of the surface of the specimens 24 h after photopolymerization. Statistical analysis was performed with one-way analysis of variance and Tukey post hoc tests at a level of significance of a=0.05 where a is the the level of significance. The light-curing mode affected the microhardness in all depths, but this influence was material-dependent (p(mat)<0.001), where p(mat) is the probability to be affected by the material. The Vickers hardness numbers of the tested composites at 0 mm ranged from 9.32 +/- 0.87 to 72.58 +/- 6.52 and those of the tested composites at 4 mm ranged from 5.48 +/- 0.32 to 54.34 +/- 2.27. The clinician has to be aware of the technical characteristics of the materials and light-curing units (LCUs) to use the most appropriate combination of LCU, composite material, and application technique. (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43392.