Teeth bleaching with low concentrations of hydrogen peroxide (6%) and catalyzed by LED blue (450 ± 10 nm) and laser infrared (808 ± 10 nm) light for in-office treatment: Randomized clinical trial 1-year follow-up

Objectives: The aim of this study was to evaluate color longevity after a year of in-office bleaching with gel (6% hydrogen peroxide HP, LED blue/laser infrared activation system) compared to a 35% control concentration in a split-mouth study model. Materials and Methods: Thirty-one patients were initially treated. The bleaching procedure with 6% or 35% gel HP was performed randomly in the upper half arcade of each patient. The color was measured at baseline and at 1 week, 1 month, and 1 year using the spectrophotometer Vita Easyshade, Vita Bleached, and Vita classical Shade guide organized by value. During the 1-year recall, the color was assessed before and after dental prophylaxis. Results: Only 27 patients were assessed in the 1-year recall. There was a significant difference in the ΔE between the two groups at all times assessed (P <.011). The ΔL, Δa, and Δb showed significant difference between both groups at all assessed times (P <.038). There was no significant difference between the ΔSGU at all times (P >.05) except for the Vita bleachedguide postprophylaxis comparison (P <.05). Conclusion: The two compounds remained effective at 1 year. When objectively evaluated, color difference between groups was found, not seen when subjectively determined. CLINICAL SIGNIFICANCE: A low concentration hydrogen peroxide bleaching agent can reach good clinical results at 1 year of follow-up.