Erosion and Abrasion of Enamel and Dentin Associated With At-Home Bleaching : An In Vitro Study

ABSTRACT BackgroundBleaching and erosive processes have been reported to soften dental surfaces, possibly increasing their susceptibility to toothbrush abrasion. The authors conducted an investigation of the effect on enamel and dentin of the interaction among bleaching, erosion and dentifrice abrasivity.MethodsThe authors prepared specimens of human enamel and root dentin and randomly divided them into eight groups that underwent 10 percent carbamide peroxide bleaching, erosion and dentifrice abrasion. The authors submitted the specimens to cycles of erosion, toothbrushing and bleaching for five days. They determined the change in surface loss by means of profilometry.ResultsDental erosion and the more abrasive dentifrice increased toothbrushing wear on enamel surfaces, while bleaching showed no deleterious effect. Dentin wear also increased after subjection to erosion and use of the more abrasive dentifrice. Bleaching increased surface loss on noneroded dentin and decreased loss on eroded dentin when it was brushed with the less abrasive dentifrice.ConclusionBleaching did not increase the susceptibility of enamel to erosive and abrasive wear, regardless of the dentifrice used. Dentin wear was modulated by the interaction of bleaching, erosion and dentifrice.Clinical ImplicationsBleaching with 10 percent carbamide peroxide does not increase erosive and abrasive wear of enamel. However, it may change dentin's abrasive wear, depending on erosive and abrasive challenges.