Comparison between the effect of low-level laser therapy and corticotomy-facilitated orthodontics on RANKL release during orthodontic tooth movement: a randomized controlled trial

Bone resorption is the cornerstone in bone remodeling affecting the rate of orthodontic tooth movement. RANKL has a direct effect on osteoclastogenesis. The aim of this study is to evaluate and compare the effect of low-level laser therapy (LLLT) and corticotomy-facilitated orthodontics (CFO) on RANKL release during orthodontic tooth movement. Twenty patients requiring orthodontic therapeutic extraction of the maxillary first premolar were randomly selected. A split-mouth study design was performed where corticotomy-facilitated orthodontics was randomly assigned to one side at the canine region (CG) before retraction, Laser group (LG) was assigned to the contralateral side using 940 nm diode laser irradiations (100 mW, 2.5 J, 3.9 J/cm2) at days 1, 3, 8, and 15. Canine retraction was done using nickel-titanium closed-coil spring applying a force of 150 g per side. Gingival crevicular fluid (GCF) samples were collected from distal surface of the canines on both sides, 1 day before the intervention treatment (T0), day 3 after the intervention (T1), and day 15 (T2). RANKL concentration levels were assessed using enzyme-linked immunosorbent assay. There was statistically significant increase in RANKL concentration levels in both groups (CG and LG) from T0 to T1, there was no statistically significant difference in concentration level from T1 o T2, but there was a statistically significant difference in RANKL concentration levels between T0 and T2 in both groups. CG and LG showed no statistically significant difference in RANKL concentration levels between them in T1 and T2. Low-level laser therapy and corticotomy-facilitated orthodontics can increase the RANKL release during orthodontic tooth movement which directly affects bone remodeling and the rate of orthodontic tooth movement.