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Efficacy of different protocols for at-home bleaching: A randomized clinical trial
Iria López Darriba1, Lourdes Novoa1, Víctor Alonso de la Peña1
1Department of Surgery and Medical and Surgical Specialties, Faculty of Medicine and Dentistry, University of Santiago de Compostela, Santiago de Compostela, Spain.
Purpose:
To evaluate the efficacy of two products used for at-home bleaching with different application times.
Methods:
80 participants were enrolled and divided into four groups, (1) 10% carbamide peroxide 1 hour a day; (2) 10% carbamide peroxide overnight; (3) 7.5% hydrogen peroxide 1 hour a day; and (4) 7.5% hydrogen peroxide overnight. The duration of treatment was 14 days. Color measurement was performed using a dental spectrophotometer on the right maxillary central incisor and the canine, at baseline and 2 weeks after. Participants recorded daily tooth sensitivity. To evaluate the influence of concentration and time on bleaching results (ΔE) the one-way ANOVA with Bonferroni post-hoc test and the Student's t-test were used.
Results:
Group 2 showed the highest value of ΔE (ΔE = 10.59 ± 2.68), followed by Group 4 (ΔE = 8.95 ± 2.32), Group 1 (ΔE = 8.05 ± 3.86), and Group 3 (ΔE = 7.08 ± 1.99). There were differences between Groups 2 and 3 (P= 0.001) and between Groups 2 and 1 (P= 0.032). The same product applied overnight was more effective than applied 1 hour a day (P< 0.05). Different concentrations during the same application time achieved similar results. The reported tooth sensitivity was mild.
Clinical Significance:
At-home bleaching is time but not concentration dependent and its secondary effects depend on the active agent concentration; therefore, there is no need to use high concentration products. The most effective protocol is low concentrations (10% carbamide peroxide) with overnight use.
