OBJECTIVES

This systematic review and meta-analysis aimed to determine the efficacy of photobiomodulation therapy (PBMT), also known as low-level laser therapy (LLLT), in reducing dental injection pain in adults.

DATA SOURCES

A comprehensive search was conducted in MEDLINE (PubMed), Scopus, Cochrane Library, Embase and Web of Science databases until June 2024. Mesh and non-Mesh keywords related to PBMT, dental injections, and pain were used. Randomized controlled trials (RCTs) comparing PBMT with a control group were included. Two independent reviewers assessed the risk of bias of the included studies using the Cochrane Risk of Bias Assessment Tool 2 (RoB2). Meta-analysis was performed using STATA version 17 on data from the studies. Heterogeneity was assessed using Chi-squared, Tau, and I-squared statistics.

STUDY SELECTION

Ten articles met the inclusion criteria, of which eight were included in the meta-analysis. The analysis using a random-effects model showed that PBMT significantly reduced the Visual Analogue Scale (VAS) pain score compared to the control group (mean difference: -1.73, 95 % confidence interval (CI): -3.25 to -0.20; P = 0.03). Studies with a consistent wavelength (940 nm) and control group also demonstrated a significant reduction in VAS pain scores with PBMT compared to controls (mean difference: -3.18, 95 % CI: -5.69 to -0.68; P = 0.01).

CONCLUSION

The results indicated that the PBMT group experienced an average reduction of 1.73 points in the VAS pain score. When comparing the consistent control group (placebo laser) and the intervention (940 nm wavelength PBMT), there was an average pain score reduction of 3.18 points with PBMT.

CLINICAL SIGNIFICANCE

PBMT is an effective method for reducing dental injection pain in adults.