In vitro evaluation of extraradicular diffusion of 6% hydrogen peroxide during intracoronal bleaching

• Published in: Revista odonto ciência 2009-01, Vol.24 (1)
• Main Authors: Brito Júnior, Manoel, Luis Faria e Silva, André, Cristina Camilo, Carla, Henrique Nogueira Guimarães Abreu, Mauro, Alves Soares, Janir
• Format: Article
• Language: English
• ISSN: 0102-9460; 1980-6523

Purpose: To evaluate the extraradicular diffusion of creamy 6 % hydrogen peroxide (HP) associated or not with sodium perborate (SP) at the cervical region of endodontically treated teeth during intracoronal bleaching. Methods: Thirty-two endodontically treated maxillary canines and central incisors were used. The gutta-percha was removed 3 mm below the cement/enamel junction, and the external root surface was covered with cyanoacrylate except for the cervical region. The teeth were randomly allocated to 4 groups: G1: 6 % HP+SP (n=11); G2: 6 % HP (n=11); G3: distilled water (negative control, n=5) and G4: 30 % HP (positive control, n=5). The specimens were immersed in a solution of potassium chromate (yellow), which turns blue in presence of HP. Two calibrated examiners (Kendall coefficient = 0.936) attributed scores according to the solution color (0 - unaltered color, 1 - light blue, and 2 - dark blue). Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (?=0.05). Results: Eighteen percent of the 6 % HP specimens with or without SP showed color alteration. Only G4 had score values statistically higher than the other groups (P=0.004). Conclusion: It can be concluded that 6 % HP cream did not have significant extraradicular diffusion during intracoronal bleaching but it was not 100 % safe. Key words: Intracoronal bleaching; hydrogen peroxide