Comparison of the Shear Bond Strengths of Two Different Gingival Colored Materials.

Objectives: The purpose of this study is to compare shear bond strengths between two different gingival colored materials bonded to titanium alloy discs and acrylic resin artificial Teeth.
Methods: 30 titanium alloy disc specimens were embedded in autopolymerizing resin. These discs were then divided randomly into two groups: 1. Heat Cure (HT¹), and 2. Pink Composite (CT¹). The discs were sand-blasted with 100 microns aluminium oxide particles. For HT¹ group and utilizing silicone molds, wax up was performed. After wax removal step, Heat-cure acrylic resin was applied and processed according to manufacture instructions. For CT¹ group and utilizing silicone molds, metal primer II and gum Opaque were applied and light cured, pink composite was applied and Light cured.
For the second part of the study, 30 artificial maxillary first molar teeth were completely embedded in autopolymerizing resin. Teeth were then divided randomly into two groups: 1. Heat Cure (HT¹), and 2. Pink Composite (CT²). For HT² group and utilizing silicone molds, wax up was performed. Samples were then transferred to be processed in heat-cure acrylic resin according to manufacture instructions. For CT¹ group and utilizing silicone molds, composite primer was applied and light cured, pink composite was then applied and Light cured.
Shear bond tests were performed, using a universal testing machine Instron 3345. The shear load in Newtons at the point of failure was recorded. The force was calculated in Mpa by calculating the failure load divided by the surface area. Two independent-samples t-tests were performed. A significance level of P < 0.05 was used for comparison.
Results: This study revealed that the difference in the shear bond strengths of two different gingival colored materials bonded to titanium discs was statistically significant (p-value = .012). The difference in the shear bond strengths of two different gingival colored materials bonded to acrylic teeth was statistically significant (p-value < .001).
Conclusions: In this in vitro study, Heat-cured acrylic resins exhibited higher bonding strengths when bonded to titanium discs or acrylic artificial teeth in comparison to the pink composite resins.