The effect of different surface treatments on tensile bond strength of acrylic denture teeth and light-cured composite resin

Abstract

This study evaluated the effect of different surface treatments on the tensile bond strength between acrylic denture teeth and composite resin. Maxillary lateral incisors of conventional acrylic denture teeth (Yamahachi New Ace) and highly cross-linked acrylic denture teeth (Trubyte Bioform IPN teeth) were ground on the labial surfaces. Each type of denture teeth were divided into six groups (n=10) according to surface treatment procedures which are no surface treatment (control), methyl methacrylate treatment (MMA) for 180 seconds, methyl formate-methyl acetate mixture (MF-MA) solution at a ratio of 25:75 (v/v) treatment for 15 seconds, composite bonding agents, MMA (180 seconds) with the application of bonding agent, and MF-MA (15 seconds) with a bonding agent. After surface treatments, light-cured composite resin was packed onto the treated surface. The tensile strength was measured using a Universal testing machine at a crosshead speed of 0.5mm/min. The data were analyzed using three-way ANOVA and post hoc Dunnett T3 test at a 95% confidence level. The denture teeth type, chemical solvents, and the use of a composite bonding agent significantly affected the tensile bond strength between acrylic denture teeth and composite resin(p<0.05). The bond strengths of the control group, MMA treated, and MF-MA treated group were not significantly different (p>0.05). For Yamahachi teeth, the bond strength of the MF-MA with bonding agent group was significantly higher than the other group (p<0.05) and the MF-MA-bonding agent treated Trubyte IPN teeth. For Trubyte IPN teeth, the MMA-bonding agent treated group showed significantly higher tensile bond strength than the other group (p<0.05). This study suggests the application of MF-MA solution for 15 s followed by a composite bonding agent before repair procedure can increase the tensile bond strength between conventional acrylic denture teeth and resin composite.