Physical-chemical characteristics of whitening toothpaste and evaluation of its effects on enamel roughness

Abstract: This in vitro study evaluated the physical-chemical characteris-tics of whitening toothpastes and their effect on bovine enamel after ap-plication of a bleaching agent (16% carbamide peroxide). Physical-chem-ical analysis was made considering mass loss by desiccation, ash content and pH of the toothpastes. Thirty bovine dental enamel fragments were prepared for roughness measurements. The samples were subjected to bleaching treatments and simulated brushing: G1. Sorriso Dentes Brancos (Conventional toothpaste), G2. Close-UP Whitening (Whitening tooth-paste), and G3. Sensodyne Branqueador (Whitening toothpaste). The av-erage roughness (Ra) was evaluated prior to the bleaching treatment and after brushing. The results revealed differences in the physical-chemical characteristics of the toothpastes (p < 0.0001). The final Ra had higher values (p < 0.05) following the procedures. The mean of the Ra did not show significant differences, considering toothpaste groups and bleach-ing treatment. Interaction (toothpaste and bleaching treatment) showed significant difference (p < 0.0001). The whitening toothpastes showed dif-ferences in their physical-chemical properties. All toothpastes promoted changes to the enamel surface, probably by the use of a bleaching agent.Descriptors: Dentifrices; Tooth bleaching; Toothbrushing; Dental Enamel.