At-home, in-office and combined dental bleaching techniques using hydrogen peroxide: Randomized clinical trial evaluation of effectiveness, clinical parameters and enamel mineral content.

Purpose: To conduct a clinical evaluation of dental bleaching techniques using hydrogen peroxide (HP), regarding tooth sensitivity, gingival irritation, subject's perception of color change, and calcium (Ca) and phosphorous (P) concentrations in enamel.

Methods: 75 volunteers were distributed according to the bleaching technique (n=25): (a) at-home: 10%HP (Opalescence GO) for 15 days of continuous use (1 hour per day); (b) in-office: 40%HP (Opalescence Boost) in three clinical sessions (40 minutes each session); (c) combined: one initial session with 40%HP, and the rest with 10%HP for 15 days of continuous use. Clinical evaluations and Ca and P concentration collections were obtained before, during bleaching treatment, and 15 days after conclusion of treatment.