Avaliação clínica de diferentes protocolos de aplicação do perióxido de hidrogênio 4% no clareamento dental caseiro.

Abstract

There is in the literature many protocols for low concentrations of hydrogen peroxide in at-home dental bleaching, but there is no consensus on the using time and frequency of the bleaching tray. Based on this information, the aim of the studies in this thesis were: Study 1) to evaluate the bleaching efficacy and tooth sensitivity in patients undergoing at-home bleaching with 4% hydrogen peroxide in two different protocols totaling two hours of gel application; Study 2) to evaluate the bleaching efficacy and tooth sensitivity in patients undergoing athome bleaching with 4% hydrogen peroxide gel in two different protocols with a total of one-hour. For this, in each study, 86 participants over 18 years old with upper right canines in color A2 or darker according to the VITA Classical scale were selected. These participants were randomly allocated to the two experimental conditions of each study: Study 1) use of 4% hydrogen peroxide gel (WhiteClass, FGM) with two daily applications of one hour each, with an interval of at most 6 hours between each application, or a single daily application for 2 consecutive hours; Study 2) use of 4% hydrogen peroxide gel (WhiteClass, FGM) through two daily applications of half an hour each, with an interval of at most 6 hours between each application, or a single daily application of 1 consecutive hour. In both studies the bleaching protocols were performed for 3 weeks. The color evaluation was carried out at the baseline, during the first, second and third weeks of the procedure and, one month after the end of bleaching, through a subjective and objective modes. Tooth sensitivity was recorded by numerical rating scale (NRS, 0-4) and visual analogue scale (VAS, 0-10). In both studies, color change was evaluated by t-test for independent samples, the relative risk for tooth sensitivity was evaluated with Fisher's exact test in Study 1 and χ2 in Study 2. The intensity of tooth sensitivity recorded by the NRS was evaluated by the Mann-Whitney test and recorded by the VAS was evaluated by the t test for independent samples (α = 0.05). After 3 weeks of bleaching the mean difference for ΔSGU Classical (1.0; 95% CI -0.1 to 2.0, Study 1 and 0.5; 95% IC -0.5 to 1.5, Study 2), ΔSGU Bleachedguide (0.7; 95% CI -0.5 to 1.9, Study 1 and - 0.4; 95% CI -1.5 to 0.7, Study 2), ΔEab (0.7; 95% CI -1.4 to 2.8, Study 1 and 1.4; 95% CI -0.1 to 2.9, Study 2), ΔE00 (0.1; 95% CI -1.4 to 1.6, Study 1 and 0.6; 95% CI -0.4 to 1.6, Study 2), and Wi (1.8; 95% CI -1.9 to 5.5, Study 1 and -3.2; 95% CI -7.3 to 0.9, Study 2) there was no statistical difference (p > 0,08). The absolute risk for tooth sensitivity was 74% (95% CI 59 to 85%, Study 1) and 44% (95% CI 30 to 58%, Study 2) for the groups that made two daily gel applications, with no difference in the intensity of sensitivity between the groups of the two studies (p > 0.65). Thus, we can conclude that there was no significant difference in the color change and in the risk and intensity of tooth sensitivity between the protocols tested in the 2 studies of this thesis.