Efficacy of Resin Cements in Bonding of Processed Composite Resin to Dentin
Objectives: Objective: To examine the efficacy of resin cements in bonding of indirect resin restorations to dentin, with and without CoJet surface treatment. Methods: Methods: Eight bovine incisors were sectioned to expose mid-dentin, and randomly assigned to four different groups: in Group 1, Lava Ultimate composite blocks were bonded to bovine dentin with RelyX Ultimate; Group 2 was treated as in Group 1 but CoJet was used to treat the intaglio surface prior to bonding; Group 3 was bonded with RelyX Unicem 2; and Group 4 was treated as in Group 3 but CoJet was used to treat the intaglio surface. RelyX Unicem 2 was used as an auto-adhesive cement, while RelyX Ultimate was used with Scotchbond Universal. All adhesives and composites were cured with a high-irradiance LED curing light (Elipar DeepCure-S). After bonding all specimens were kept in 100% humidity and 37oC for 7 days and then were processed for microtensile bond strengths (μTBS) testing (n=15). The number of pre-test failures was uniform across groups (n=2-4). Data were analyzed for statistical significance using two-way ANOVA and Tukey’s HSD post-hoc test (p=0.05). Results: Results: The results for the μTBS are shown in the table. Conclusions: Conclusions: The resin cement RelyX Ultimate performed significantly better than the auto-adhesive resin cement RelyX Unicem 2. Surface treatment with CoJet improved bond strengths of Lava Ultimate to dentin regardless of the resin cement used.