The Effectiveness of Low-Level Laser Therapy in Pain Induced by Orthodontic Separator Placement: A Systematic Review

Introduction: This systematic review was conducted to evaluate the effectiveness of low-level laser therapy (LLLT) in orthodontic separator pain. Methods: This article was written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Electronically and manually 3 databases, namely PubMed, Scopus and Google Scholar, were searched by the keywords that were selected based on population, intervention, comparison and outcome (PICO) on October 10, 2020. Studies were appraised by Cochrane version 5.2.0 with 7 domains and were checked by these inclusion criteria: 1. Randomized clinical trial (RCT) that examined the efficacy of LLLT in separator pain, 2. Split-mouth design, 3. LLLT application in the first hours after separator placement, 4. LLLT application to both sides of the teeth, 5. Patients receiving elastomeric separators between the premolars and molars, 6. Lasers with a wavelength of 800-899 nm, 7. Studies conducted from 2010 to 2020, and 8. Participants who went through orthodontic treatment without limitation in gender, age and social-economic status. Results: 299 studies were screened. 34 full-text papers were read by 2 authors independently. In the end, 4 articles met the inclusion criteria. All 4 articles showed LLLT has a significant impact on pain reduction. Conclusion: The exact protocol for laser therapy is still not clear. Therefore, more studies with a meticulously designed method are needed.