The effect of curing conditions on the dentin bond strength of two dual-cure resin cements

Purpose: The purpose of this study was to determine the effect of the curing condition (i.e., the curing mode and restoration thickness) on the tensile bond strength of a dual-cure resin cement applied to dentin. Methods: Indirect composite resin disks (1, 2, and 3mm in thickness) were prepared. The irradiance of a halogen light curing unit through each disk was measured by a curing radiometer. A measurement was also taken for the condition with no disk. Following this, two dual-cure resin cements, Panavia F2.0 and Panavia V5, were polymerized in either dual-cure mode or self-cure mode to bond the composite resin disk to the flat dentin surface. The specimens were sectioned and subjected to a microtensile bond strength (mu TBS) test after 24h of water storage. The data were statistically analyzed by two-way ANOVA followed with multiple comparisons by post-hoc Tukey's test (alpha=0.05). Results: The irradiance values [mW/cm(2)] measured through indirect composite resin disks were 600 (0mm), 200 (1mm), 90 (2mm), and not detected (3mm). Two-way ANOVA indicated that both the curing condition and the type of resin cement affected the mu TBS (p<0.001). The mu TBS results for Panavia V5 bonded to dentin were significantly higher than those of Panavia F2.0 bonded to dentin (p<0.05). Conclusions: The curing condition affected the tensile bond strength of the dual-cure resin cements to dentin. A newly developed resin cement, Panavia V5, showed higher dentin bonding than Panavia F2.0 in both dual-and self-cure modes. (C) 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.