The Effectiveness of Different Clinical Methods of Application for In-office Bleaching Materials with Hydrogen Peroxide: A Systematic Review

Background: In the past few years, there has been an increase in demand for esthetic dental treatment. Vital tooth-bleaching is one of the most popular cosmetic procedures requested by patients in daily dental practice. There are various materials and protocols for treating discolored teeth since the introduction of vital tooth-bleaching to dental practice. In-office bleaching can be performed clinically using hydrogen peroxide alone or it can be combined with carbamide peroxide as a home bleaching technique. Hence the aim of this systematic review was to evaluate the effectiveness of different application protocols. Methodology: A comprehensive search was performed using online databases (PubMed and ADA Center for Evidence-Based Dentistry) to obtain clinical trials relevant to the research question. The readers validated the studies that met the inclusion criteria. The included studies were evaluated using the risk of bias assessment instrument. In addition, the strength of recommendation of clinical trials was evaluated using Ex-GRADE. Results: After reviewing 89 studies, duplicates were removed and inclusion and exclusion criteria were applied. Finally 10 clinical studies were accepted in this review. Acceptable sampling was performed to obtain the clinical trials with strong evidence. Conclusion: A qualitative assessment for the included studies proved the hypothesis of the research in that the best clinical outcomes of in-office bleaching is achieved with a single application of hydrogen peroxide.