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VOLUME 12 , ISSUE 2 ( March-April, 2011 ) > List of Articles


pH-changes during Intracoronal Bleaching: An in vivo Study

Daphne Câmara Barcellos, Alessandra Buhler Borges, Regina Célia dos Santos Pinto Silva, Luciana Maria Ribeiro, Cesar Rogério Pucci, Carlos Rocha Gomes Torres

Citation Information : Barcellos DC, Borges AB, Silva RC, Ribeiro LM, Pucci CR, Torres CR. pH-changes during Intracoronal Bleaching: An in vivo Study. J Contemp Dent Pract 2011; 12 (2):109-113.

DOI: 10.5005/jp-journals-10024-1018

Published Online: 01-02-2012

Copyright Statement:  Copyright © 2011; The Author(s).



This study aimed to measure pH changes during 14 days intracoronal bleaching with hydrogen peroxide/sodium perborate and carbamide peroxide/sodium perborate.

Materials and methods

Twenty patients presenting endodontically treated central maxillary incisors with color alterations were divided in two groups (n = 10): Group CP + SP: 37% carbamide peroxide + sodium perborate paste; Group HP + SP: 30% hydrogen peroxide + sodium perborate paste. The pH values were measured using a digital microprocessor at different times: Baseline, 2, 7 and 14 days. Data were analyzed with two-way ANOVA followed by Tukey's test (á = 0.05).


ANOVA showed p < 0.00 which indicated significant difference between the groups. The mean values (± sd) and the results of the Tukey's test were: HP + SP/14 days—7.98 (±0.58)a; HP + SP/7 days—8.59 (±0.18)b; HP + SP/2 days— 8.83 (±0.32)bc; HP + SP/Baseline—8.83 (±0.01)bc; CP + SP/ Baseline—8.89 (±0.01)bc; CP + SP/14 days—9.11 (±0.58)cd; CP + SP/7 days—9.54 (±0.16)de; CP + SP/2 days—9.66 (±0.08) de. The group HP + SP resulted in significantly lower pH values compared with group CP + SP.


It can be concluded that both associations showed alkaline pH values; however, there was significant reduction in the pH values of the 30% hydrogen peroxide associated with sodium perborate after 14 days.

Clinical Significance

The association of hydrogen peroxide and carbamide peroxide with sodium perborate paste presented alkaline characteristics during the 14-day evaluated period. Thus, regarding pH changes, both associations can be considered safe as intracoronal bleaching agents.

How to cite this article

Barcellos DC, Borges AB, Silva RCDSP, Ribeiro LM, Pucci CR, Torres CRG. pH-changes during Intracoronal Bleaching: An in vivo Study. J Contemp Dent Pract 2011;12(2):109-113.

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