Comparative Evaluation of Antioxidants on Bond Strength After At-home Whitening: An In Vitro Study

from one day to two weeks before getting any restorative procedures done, such as veneers, composite restorations, or gluing orthodontic brackets to the bleached enamel.5 This waiting period is necessary because the free radicals released during the bleaching process become trapped in the enamel region between the prisms.These residual free radicals interfere with the polymerization of resin-based materials by inhibiting the propagation of free-radical polymerization reactions, ultimately compromising the formation of a stable hybrid layer and reducing adhesive strength.6,7 However, this waiting period is not always IntroductIonTeeth whitening procedures are mainly carried out to remove intrinsic or extrinsic tooth discoloration.The increasing demand for minimally invasive cosmetic treatments among genders has led to the widespread use of bleaching agents such as hydrogen peroxide and carbamide peroxide.In teeth-whitening procedures, it has been shown that using different quantities of hydrogen peroxide and carbamide peroxide significantly increases the patient's esthetic satisfaction.1,2 An oxidationreduction event occurs, leading to the degradation of hydrogen peroxide into reactive oxygen species (ROS), specifically hydroxyl and perhydroxyl species.These highly reactive molecules interact with organic chromophores within the enamel and dentin, breaking down complex pigmented molecules into smaller, less pigmented structures, thereby resulting in tooth whitening.3 A previous study found that the present bleaching materials and procedures have a number of drawbacks, such that they raise surface roughness while lowering surface microhardness, mineral content, and bond strength.4 The reduction in bond strength is of particular clinical concern, especially in cases where restorative procedures such as composite restorations, veneers, or orthodontic bracket bonding are required following bleaching.Moreover, to overcome this issue, there is a need to wait anywhere