Discussion
tooth
ADVERSE EFFECTS, INFLAMMATORY RESPONSE
The results of this study showed that 6% HP, despite the difference between the tips used, promoted significant bleaching, with a lower TS pattern and a significant difference in aesthetic self-perception after the procedure among the adolescents evaluated. This finding is of significant importance, especially since, as explained in the Introduction section, a higher prevalence of TS is expected in younger patients due to the greater permeability of their teeth. The 6% HP applied in the study uses self-mixing tips that combine the two phases of the bleaching gel with different application tips and can be found in two ways. Considering these facts, regarding color change, this study used different evaluation parameters to better validate the results. Two subjective scales were used, the VITA Classical, Significant bleaching was detected for both study groups compared with baseline values. For the subjective (VITA Classical and VITA Bleachedguide) and objective (∆E The favorable bleaching results for the without brush group can be attributed to the amount of gel used. When assessing the 50:50% perceptibility threshold for the ∆WI One of the most common adverse effects observed during and after tooth bleaching is TS, and many alternatives have been studied to reduce this undesirable outcome, especially in adolescents, as aforementioned in the Introduction section. Since TS occurs due to the ability of HP to penetrate the tooth structure and cause an inflammatory response in the pulp, Comparing the results of this study with the literature, some differences in terms of the absolute risk of TS can be observed. One of the most important results of this study is the assessment of aesthetic self-perception, since it is a patient-reported outcome that characterizes specific influences of oral health on patients’ lives and this assessment is already considered essential. Despite the favorable results in this study regarding in-office bleaching with 6% HP, it should be noted that the same level of bleaching efficacy should not be expected, especially when 6% HP is applied using a tip with a brush compared with more concentrated in-office bleaching gels, as previously tested in both Low-concentration in-office bleaching provided promising results. The use of 6% HP for the in-office technique has some advantages over at-home bleaching. In-office bleaching does not depend on the patient’s collaboration and is easier to be performed, as it does not require individualized trays, which adolescents find difficult to use. Some limitations need to be described. Our study evaluated only one commercial brand of bleaching gel, and future studies should evaluate different HP 6% bleaching gels available in clinical settings. Another limitation is the bleaching protocol, which made it difficult to compare this study with others, given the variability in application time or number of sessions, the association with light, and other factors, 