Elemental and morphological analysis of enamel following the application of two bleaching systems with amorphous calcium phosphate: effect on enamel erosion susceptibility

Abstract

Abstract Background Using remineralizing agents during and after bleaching procedures could maintain enamel surface, decreasing its erosive susceptibility. This study evaluated the efficacy of an in-office and at-home bleaching materials with amorphous calcium phosphate (ACP) on the susceptibility of the enamel to erosion. Forty-five bovine specimens were separated into three groups. Group A: no bleaching (control). Group B: Zoom 2 bleaching followed by ACP application. Group C: Nite White ACP. All specimens in all groups were subjected to an erosive challenge for five days. Using Energy Dispersive X-ray all specimens were subjected to elemental analysis and were examined for morphological changes under Scanning Electron Microscope (SEM). Results Group B showed the highest mean calcium, phosphorus and sodium weight percent (wt%). Both Groups B and C showed statistically significant difference. While, there was no statistically significant difference between both Groups A and B.The sodium mean wt% showed a statistically significant difference in all groups. The magnesium mean wt% showed no statistically significant difference in all groups. SEM photomicrograph revealed hollowing of prism cores with intact prisms peripheries for group A. Group B showed relativity smooth surface with minor pores, while Group C showed an increase in the depth of surface irregularities and depressions. Conclusions Enamel susceptibility to erosion after bleaching procedure was material dependent. Zoom 2 bleaching agent followed by ACP application did not increase the susceptibility of the enamel surface to erosion. Adding ACP to Nite White bleaching agent had no benefit on reducing enamel susceptibility to erosion.

Keywords

• Enamel erosion
• Demineralization
• Bleaching
• Amorphous calcium phosphate
• Acidic challenge