Jadad, EnriqueMontoya, JaimeArana, GonzaloArana Gordillo, Luis AlfonsoMiotto Palo, RenatoD. Loguercio, Alessandro2020-10-012020-10-012011-07-010889-5406https://repositorio.usc.edu.co/handle/20.500.12421/4335Introduction: Our objective was to assess the effectiveness of a new bleaching agent (8% hydrogen peroxide) used in patients wearing fixed orthodontic appliances. Methods: Six anterior maxillary teeth of 40 patients aged 18 to 40 years were assessed. The patients were divided into 2 groups (20 in each group): in group A, the patients used the bleaching agent during orthodontic treatment; in group B, the patients used the bleaching agent after orthodontic treatment. For each group, a record of the initial tooth shade was taken with a polyvinyl siloxane matrix and a spectrophotometer. The groups had bleaching treatments with an 8% hydrogen peroxide product (Opalescence Treswhite Ortho, Ultradent, Opal Orthodontics, South Jordan, Utah) for 10 days in 45-minute sessions. For group A, the treatment was performed 10 days before finishing orthodontic treatment; at the end of the treatment, a new tooth shade record was taken with the polyvinyl siloxane matrix and a spectrophotometer. The subjects in group B had the same bleaching protocol after their brackets were removed. Results: It was observed that, for the group without brackets, the color alteration ranged from 3 to 12 (mean, 8; median, 8.3); for the group with brackets, the range was between 4 and 13 (mean, 9; median, 8.5), indicating significant tooth bleaching in both groups with and without brackets (P >0.05). Conclusions: Opalescence Treswhite Ortho was shown to be an efficient bleaching agent in patients wearing fixed orthodontic appliances.enArticle