Evaluation the Effect of Diazonium Salt and Aluminum Oxide on the Shear Bond Strength of Heat Cure Acrylic Resin at Co/Cr and Titanium Alloys Interface

Abstract

Bonding between metal components and denture base resin plays an important role in the success of removable partial denture. Removable partial denture prostheses often present a mechanical failure. The bonding between metal framework and acrylic resin is usually a mechanical interlock, since they do not chemical bond spontaneously. The aim of this study was to evaluate the effect of different surface treatments (diazonium salt and aluminum oxide) on the shear bond strength of PMMA at the Co/Cr and titanium alloys interface. Sixty-disc shape specimens were prepared and divided into 2 main groups according to the type of material, 30 specimens for Co/Cr alloy and 30 specimens for titanium alloy, then subdivided into 3 groups each one consist of 10 specimens, according to type of surface treatments. Each group had control group, aluminum oxide group (110 μm), and diazonium salt group. The specimens were thermocycled (3000 cycles) after applications of PMMA. Shear bond strength test conducted with crosshead speed 0.5mm/min. Data analyzed via One-way ANOVA and GHD test. Co/Cr alloy revealed that diazonium salt surface treatment had highest mean value of shear bond strength followed by aluminum oxide surface treatment at p<0.01. For titanium alloy, the results showed the diazonium salt surface treatment had highest mean value of shear bond strength followed by aluminum oxide surface treatment group at p<0.01. Aluminum oxide treatment slightly increased shear bond strength for both Co/Cr and titanium, while diazonium salt treatment statistically increased shear bond strength for Co/Cr and titanium alloy.