Influence of a short‐time antioxidant application on the dentin bond strength after intracoronal bleaching

Abstract

This study evaluated the effects of an antioxidant application on the compromised bond strength of an adhesive to dentin bleached with 35% hydrogen peroxide. The dentin surfaces of the pulp chambers of 70 human third molars were ground, and the specimens were assigned randomly into seven groups, as follows: (a) control (unbleached); (b) bleached for 45 min, bonded immediately; (c) bleached for 45 min, treated with sodium ascorbate (SA) for 2 min, and bonded; (d) bleached for 45 min, bonded after 2 weeks; (e) bleached for 12 days, bonded immediately; (f) bleached for 12 days, treated with SA for 10 min, and bonded; and (g) bleached for 12 days, bonded after 2 weeks. In each group, the multimode adhesive was applied in etch‐and‐rinse and self‐etch modes. The dentin surfaces were covered with a resin‐based composite, and the bonded specimens were sectioned to produce composite–dentin sticks. The sticks were attached to a testing machine and subjected to a tensile force, and the representative specimens were examined via scanning electron microscopy. The bond strength was not affected by the application period of the bleaching agent. Both bleaching treatments significantly reduced the bond strength to the dentin in the self‐etch or etch‐and‐rinse mode when compared with the control group. The bond strengths returned to normal levels with the SA applications or by waiting 2 weeks, regardless of the application period of the bleaching gel. The adhesive revealed a higher bond strength in the etch‐and‐rinse mode than in the self‐etch mode.

Evaluation the Effect of Different Antioxidants Applied After Bleaching on Teeth Color Stability

“…In this respect, the results are not consistent with this study. This difference might be explained by the differences in the procedure, such as concentration and duration, which are known to affect bond formation results in antioxidant procedures [41,42]. No significant change was observed in ∆L 2 , ∆a 2 and ∆b 2 values.…”

Comparative Evaluation of Two Antioxidants on Reversing the Immediate Bond Strength of Bleached Enamel: In Vitro Study

“…It is advantageous due to its harmlessness to the tooth and surrounding tissues, simple operation, safety, and quick effect. To date, bleaching agents, such as hydrogen peroxide with concentration from 30% to 40% or carbamide peroxide with level from 35% to 37%, have been applied in clinics successfully, getting satisfying aesthetic results [3,4,6,[8][9][10]15,35]. However, most scholars suggested tooth bleaching can decrease the immediate BS-RBE [4][5][6][7][8][9]15,36].…”

“…It is due to bleaching agents damage the surface morphology of enamel. Besides, hydrogen peroxide is decomposed into free radicals and oxygen, which interfere with resin penetration and prevent polymerization of the resin [6,21,37]. Various methods to reverse the decrease of BS-RBE are available, including antioxidant treatment, ethanol pretreatment of enamel surface after bleaching before resin bonding, the utilization of an adhesive containing an organic solvent, and the removal of the enamel surface [14,27,38,39].…”

“…Nevertheless, it increases the number of office visits, thus bringing great inconvenience to patients [23]. In recent years, antioxidant treatment has provided us with promising results to reverse the decline of BS-RBE [3][4][5][6][7][8][9][10][11][12]14,19,23,40]. Currently, a variety of antioxidants are used to enhance BS-RBE.…”

Effects of remaining dentin thickness on the bond strength of bleached dentin

“…Alternations in the surface morphology and structure of dentin [7,9,10], loss of mineral content [7,9,10], increase in dentin permeability [7], and metalloproteinasemediated collagen degradation in dentin [7,11] have been reported after intracoronal bleaching. Moreover, there is evidence that tooth bleaching may lead to a reduction in the bond strength of resin composites applied to previously bleached dentin [5,[12][13][14][15][16]. However, contrasting results regarding the bond strength of bleached dentin have been reported in the literature.…”