Evaluation of low-level laser therapy on TGF-β1 levels in gingival crevicular fluid during canine distalization: A randomized controlled trial

Background: Orthodontic treatment typically requires 20-30 months, which can lead to decreased patient compliance and increased risk of complications. Low-level laser therapy (LLLT) has emerged as a promising non-invasive method to accelerate orthodontic tooth movement by enhancing bone remodeling. Transforming Growth Factor-beta 1 (TGF-β1) is a key cytokine involved in bone remodeling during orthodontic tooth movement. Methods: A split-mouth randomized controlled trial was conducted with 15 patients requiring bilateral first premolar extractions. One side received LLLT (810 nm, 100 mW, 4 J/cm²) on days 0, 3, 7, 14, and 21, while the contralateral side served as control. GCF samples were collected from tension and compression sides at baseline (T0), day 1 (T1), day 7 (T2), day 14 (T3), and day 21 (T4). TGF-β1 levels were analyzed using ELISA. Statistical analysis was performed using unpaired t-test and paired t-test with significance set at p