An In vitro Study to evaluate the Effect of Surface Treatment Methods of Acrylic Teeth on Bond Strength to Light-Cured Composite

Abstract

Background & Aim: both wear and fracture of artificial teeth are essential problems in removable prosthodontics because they cause functional and esthetical problems. Light-cured composite resin or acrylic resin can be used to repair acrylic resin teeth fracture. However, the research published on the shear bond strength between acrylic denture teeth and composite resin is very limited.

Purpose: to investigate the effect of different surface treatment methods on shear bond strength between light-cured composite resin and acrylic resin teeth.

Materials and Methods: 60 lower molars acrylic resin teeth were divided into four groups, each one contains 15: group (I)  (control): received no surface treatment, group (II) received bond agent only, group (III) received MMA (methyl methacrylate) with bond agent, and group (IV) was etched by phosphoric acid %37 with bond agent. All groups (from I to IV) received a cylinder of light-cured composite resin (diameter=4 mm, height=2 mm). Shear bond strength was measured using a universal testing machine (Testometric). Data was analyzed using one-way analysis of variance (One-Way ANOVA) and Tukey post hoc (α=0.01).

Results: shear bond strength of groups II, III, and IV was greater than that of the control group. Shear bond strength of group IV was lower than that of groups II, and III. There were no significant differences between groups II, and III.

Conclusion: with the limitations of this study: bond agent increased shear bond strength. There was no difference of shear bond strength when applying MMA prior bond agent. Applying phosphoric acid %37 prior bond agent is useless.