Photobiomodulation and its Effect on Stability of Orthodontic Mini-implants: A Systematic Review and Meta-analysis of Randomised Controlled Trials

Abstract

Introduction: The influence of Photobiomodulation (PBM) in the field of orthodontics has been of recent interest. PBM has a promising effect on acceleration of tooth movement, alleviation of pain during orthodontic treatment and Mini-Implant (MI) stability. Aim: The aim of this review was to systematically report on the effectiveness of PBM on the stability of orthodontic MI. Materials and Methods: Literature search was conducted in five electronic databases for human trials published between January 2000 to February 2021 on the effectiveness of PBM therapy for stability of orthodontic MI. This systematic review was conducted during January 2021 and February 2021. Cochrane review manager software (Revman version 5.4) and Cochrane Risk Of Bias (ROB) 2 tool were used for bias assessment. The primary outcome measured was the stability of MI using Resonance Frequency Analysis (RFA) or Periotest Value (PTV). The secondary outcomes measured were pain and inflammation around the peri-implant area. Also, Interleukin-1β (IL-1β) was also measured in gingival crevicular fluid. Results: A total of six Randomized Controlled Trials (RCTs) were included in the review. Out of the 6 studies, 2 showed low Risk Of Bias (ROB) whereas 3 showed some concerns and 1 showed high ROB. Quantitative analysis was done for 4 studies with a random effects model to assess the MI stability measured by periotest at 30 days and 60 days. A significant mean difference of -3.31 (95% CI-5.15,-1.47) between PBM and controls for mini-implant stability at 30 days and a significant mean difference of -3.47 (95% CI-4.58, -2.36) between PBM and controls at 60 days with low heterogeneity was obtained. Three studies reported on the pain response after PBM and both groups showed no significant difference. A decrease in gingival inflammation was reported in one study whereas other study showed no significant change in IL-1ß in gingival crevicular fluid. Conclusion: Majority of the studies included in this review reported improved secondary stability with PBM. The low heterogeneous nature of the quantitative studies also supports the data obtained. However, the results should be concluded with caution.