Deleterious Effects over Enamel Surface Bleached with Low and High Concentration Gels Containing Calcium – in vitro Evaluation

2022 • Volume 16 • Issue 1

Kandice Valente Martins; Rayssa Ferreira Zanatta; Fabiana Tavares Lunardi Palhari; Maria Beatriz Freitas D’Arce & Priscila Christiane Suzy Liporoni



The objective of this study was to evaluate the morphological effects of bleaching with hydrogen peroxide 40 % (HP 40 %) and carbamide peroxide 20 % (CP 20 %), with and without the addition of calcium (2000 ppm), in enamel. Bovine enamel blocks (25 mm2) were randomly divided into 5 groups (n=12) accordingly to the bleaching gel (HP 40 % and CP 20 %) and the presence of calcium (with and without). Control group were immersed in artificial saliva. The treatments were carried out for 14 days. Roughness (Ra) and Knoop microhardness analysis were performed for enamel surface before and after treatment. Data were analyzed by repeated measures ANOVA and Tukey test (p<0.05). The bleached group with 40 % HP had the lowest values of microhardness. There was a statistically significant difference between the initial and final readings. For surface roughness were no differences between the tested materials; but there was an increase of roughness for all groups after bleaching. It was concluded that all bleaching agents tested promoted a surface microhardness decrease after treatment, however the calcium addition promoted a slighter surface alteration, and all bleaching agents promoted a surface roughness increase after treatment.

KEY WORDS: bleaching agents, dental enamel, hydrogen Peroxide, carbamide peroxide.


How to cite this article

MARTINS, K. V.; ZANATTA, R. F.; PALHARI, F. T. L.; D’ARCE, M. B. F.; LIPORONI, P. C. S. Deleterious effects over enamel surface bleached with low and high concentration gels containing calcium – in vitro evaluation. Int. J. Odontostomat.,16(1):120-124, 2022.


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