Effects of matrix composition and surface treatment on the bond strength of glass fiber-reinforced composite posts to root dentin

Abstract

Objective: This study evaluated the effects of resin matrix composition and surface treatment on the bond strength of glass fiber-reinforced composite (FRC) posts to intraradicular dentin.Methods: Fifty-six extracted premolars were obtained. Post spaces were prepared for either epoxy resin-based posts (White Post DC) or Bis-GMA-based posts (Postec Plus) (n=28). The posts received different surface treatments (n=7): 70% ethanol (control), air abrasion and silanization, 35% H3PO4, and 24% H2O2. Posts were cemented and the samples were sectioned into cervical, middle, and apical thirds. The push-out bond strength of samples was compared between the groups using two-way ANOVA (α=0.05).Results: There was a significant difference in bond strength between the different treatment methods in all root sections (P 0.05). Additionally, their bond strengths were comparable in the middle section when the post surfaces were treated with air abrasion and silanization, or 35% H₃PO₄ (P > 0.05).Conclusions: Air abrasion and silanization could be suggested as the optimal surface treatment strategy to improve the bond strength of FRC posts to resin cement. Proper mechanical and chemical surface treatments might be more important than the resin matrix composition in determining the bond strength of FRC posts.

Keywords

• air abrasion
• bisphenol a-glycidyl methacrylate
• bond strength
• epoxy resins
• fiber post
• silane