Randomized controlled trial of sealed in-office bleaching effectiveness.

Regardless of the high success rate, patients commonly report the occurrence of tooth sensitivity during the in-office bleaching procedures. Recently, it has been demonstrated that using a customized tray (called sealed in-office bleaching technique) reduces peroxide penetration. The aim of this randomized clinical study was to evaluate tooth sensitivity and bleaching efficacy of sealed bleaching, in comparison with a conventional in-office technique. Twenty patients were randomized allocated in two groups in which 35% hydrogen peroxide gel was used in a single 45-min application. For the sealed technique, a customized bleaching tray was fabricated and carefully positioned over the bleaching agent during the session. The color was recorded at a baseline, 7 and 28 days after the bleaching session, using Vita Easy Shade spectrophotometer. Tooth sensitivity was recorded during (20 and 40 min) and immediately after the treatment using a visual analogue scale. The bleaching efficacy was evaluated by repeated-measures ANOVA, while the absolute risk of tooth sensitivity and its intensity were evaluated by Fisher's exact and Mann-Whitney tests, respectively (α=0.05). No significant difference on bleaching efficacy was observed between the conventional (7.4 and 8.1 ΔE) and sealed techniques (7.8 and 8.3 ΔE) at both evaluation periods. No significant difference was observed regarding the absolute risk of tooth sensitivity (p=0.15). Sealed technique showed a significant decrease of sensitivity intensity after 40 min (p=0.03). Sealed bleaching technique was able to reduce the sensitivity intensity during the bleaching procedure, without jeopardizing the bleaching efficacy.