Effect of Sodium Ascorbate Concentration after Bleaching on the Enamel Shear Bond Strength of Giomer Resin
The aim of this in-vitro study was to evaluate the application of different concentrations of sodium ascorbate (SA) on the strength of bonding to enamel after bleaching with hydrogen peroxide (HP). Forty human anterior teeth were randomly divided into four groups. Group 1 was treated with no bleaching application (negative control), and the treatments applied in the other groups were: Group 2; 35% HP for 30 min + 40% SA for 10 min, group 3; 35% HP for 30 min + 20% SA for 10 min, and group 4; 35% HP for 30 min + 10% SA for 10 min. Specimens were restored with adhesive All-Bond Universal (Bisco, Schaumburg, IL, USA), and a Beautifil-2 (Shofu Inc., Kyoto, Japan) giomer-resin material build-up was created. The specimens were subjected to shear bond testing by a universal machine. The data were analyzed with the Kruskal Wallis test followed by the Mann Whitney test, and p < 0.05 was deemed to indicate statistical significance. The unbleached teeth showed the highest shear bond strength, followed by the bleached teeth treated with 40% SA. Within the limitations of this study, it can be concluded that SA increased the potential bond strength associated with bleached enamel. Notably however, none of the different concentrations of SA tested restored the bond strength values to those of the unbleached teeth.
