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In-office tooth bleaching effectiveness with different soft-tissue barriers – randomized controlled trial

Objectives: To evaluate the tooth bleaching effectiveness of a 6% hydrogen peroxide paint-on varnish with two different types of soft-tissue protection materials. Methods: Twenty patients were screened according to inclusion and exclusion criteria, submitted to professional dental prophylaxis, and randomly allocated to one of the two groups. An in-office bleaching technique protocol was performed (VivaStyle Paint On PIus, lvoclar- Vivadent®, Liechtenstein) with two different soft-tissue protection materials: Group 1 – Vaseline; Group 2 – block-out resin. Bleaching effectiveness was evaluated with ΔE00 and ΔWID, calculated from the CIE L*a*b* values obtained by spectrophotometry analysis (SpectroShade). Appropriate statistical tests were performed to analyze intragroup differences in CIE L*a*b* and WID values and intergroup differences in ΔE00 and ΔWID with α=0.05. Results: Both groups presented statistically significant (P<0.01) differences in CIE L*a*b* and WID. Both ΔE00 and ΔWID surpassed the acceptability threshold (ΔE00 > 1.8; ΔWID > 2.60), and the ΔWID was mostly classified as hardly acceptable differences. Group 2 presented higher statistically significant (P<0.01) mean values with ΔE00 = 3.5 ± 1.5 and ΔWID = 8.6 ± 4.2. Conclusions: The 6% hydrogen peroxide paint-on varnish tooth bleaching technique showed clinical effectiveness. However, effectiveness varied with the soft-tissue protection material used, with better results when applying a block-out resin, thus suggesting its clinical recommendation.