Evaluation of Tooth Sensitivity During In-Office Bleaching with Laser Irradiation: A Systematic Review and Meta-Analysis

Introduction: This systematic review and meta-analysis aimed to evaluate the impact of laser irradiation during in-office bleaching on tooth sensitivity. Methods: A comprehensive search was conducted in PubMed, Scopus, and Web of Science for randomized controlled trials (RCTs) published up to August 2025 that assessed tooth sensitivity following laser-assisted in-office bleaching. The primary outcome was sensitivity intensity, measured using the Visual Analog Scale (VAS). A total of 230 records were retrieved, 31 fulltexts were assessed, and 4 RCTs were included in the final analysis. Data were extracted, and meta-analyses were performed using a random-effects model. Results: Four RCTs were included. All included studies used diode lasers (wavelengths: 810–980 nm). The meta-analysis demonstrated a significant reduction in post-bleaching tooth sensitivity with laser irradiation compared to the control group (WMD=1.174; 95% CI: 0.474 to 1.874; P=0.001). However, high heterogeneity was observed (I²=99.93%). Sensitivity analyses confirmed the robustness of the findings, though potential publication bias was suggested. Conclusion: Laser irradiation during in-office bleaching appears to significantly reduce tooth sensitivity compared to conventional methods, potentially improving patient comfort. Nonetheless, the high variability among studies highlights the need for further well-designed clinical trials with standardized protocols to confirm these results and optimize laser parameters.