Effect of low-intensity laser therapy on levels of biomarkers during orthodontic tooth movement – A systematic review

Abstract

This systematic review aimed to explore the association between low-intensity laser therapy (LILT) and various biomarkers, elucidating the potential of this therapeutic modality to expedite orthodontic tooth movement (OTM). A systematic literature search was conducted using electronic databases including PubMed, Central of the Cochrane Library, and Google Scholar databases. Randomized controlled trials (RCTs) and non-randomized controlled clinical trials (nRCTs) using LILT as an adjunct to the standard orthodontic procedures in human and animal subjects as participants were included in the study. The quality of the human and animal studies was assessed using the Revised Cochrane risk of bias tool and Systematic Review Centre for Laboratory Animal Experimentation’s (SYRCLE’s) risk of bias tool respectively. Animal studies revealed increased receptor activator of nuclear factor-kappa B (RANK)/RANK ligand (RANKL), matrix metalloproteinase-9 (MMP-9), and collagen type I expression. Human studies showed elevated interleukin-1-beta (IL-1β), interleukin-16 (IL-16) and RANKL levels, suggesting LILT influences biomarkers associated with bone resorption and connective tissue rearrangement. A high risk of bias was observed in all animal studies and 5 out of 6 human studies. The systematic review concluded that LILT emerges as a promising technique for enhancing orthodontic tooth movement, influencing key biomarkers linked to osteoclastic activity and collagen synthesis. However, the high risk of bias in animal and human studies emphasizes the need for further research to validate findings and optimize laser parameters for clinical benefits.