Shear Bond Strength Between Composite Resin and Denture Teeth: Effect of Tooth Type and Surface Treatments

Purpose: The purpose of this study was to investigate the strength of the composite resin- denture tooth bond as affected by different tooth surface treatments. Materials and Methods: Spectrum TPH was condensed on 112 mandibular first molar acrylic resin and composite resin denture teeth, which received seven different treatments: Four groups were treated with Prime & Bond NT adhesive, and three groups were treated with One Step adhesive. Four groups (two of each adhesive category) were treated with Composite Activator and air abrasion. In one group, AeliteFlo was used just before the condensation of Spectrum TPH. Bond strength was evaluated with a shear test device on a Monsanto testing machine. The results were evaluated statistically with two-way ANOVA and the Scheffé method. Results: There was a significant interaction between denture tooth type and surface treatments. Bond strength of composite resin was greater to composite than to acrylic resin teeth when the bond was mediated only with adhesives. One Step adhesive and AeliteFlo resulted in a higher bond of composite resin to both types of teeth. Wetting tooth surfaces with Composite Activator did not increase the bond. Conclusion: When repairing denture teeth with composite resin and adhesives, the bond strength was higher with composite than with acrylic resin teeth, and there were differences between the adhesives used.