Evaluation of Laser Therapy During Orthodontic Treatment in Adult Patients by Determining N-Telopeptide Levels in Gingival Crevicular Fluid

<i>Background and Objectives</i>: Orthodontic tooth movement triggers micro-trauma in the periodontal ligament, leading to a balanced process of bone resorption and apposition mediated by local inflammatory responses. Monitoring N-telopeptide levels in gingival crevicular fluid (GCF) and applying low-intensity laser biostimulation can help optimize mechanical loading, reduce adverse effects, and enhance tissue remodeling during treatment. <i>Materials and Methods</i>: This study had a split-mouth observational design. From 30 patients with ages between 20 and 50, with standardized fixed orthodontic treatment, GCF samples were collected from both control and laser-treated hemiarches before and 14 days after appliance activation. Low-intensity laser therapy (LLLT) was applied to selected sites to assess its effect on N-telopeptide levels, a marker of bone resorption, with samples analyzed via ELISA and results compared statistically to evaluate the impact of laser biostimulation during orthodontic treatment. Statistical analysis was performed using paired <i>t</i>-tests or Wilcoxon tests for two-group comparisons. <i>Results</i>: N-telopeptide levels in gingival crevicular fluid increased significantly from baseline (T0) to 14 days (T1) in both the laser-treated (HL) and control (sham) hemiarches (HC), with higher values observed in the lasered side. Statistical analysis confirmed significant differences between HL and HC at T1 (<i>p</i> < 0.0001), as well as between each T1 group and baseline, indicating that low-intensity laser therapy enhanced bone resorption activity during orthodontic tooth movement. <i>Conclusions</i>: N-telopeptide exhibited higher values in the hemiarches where laser therapy was applied than in the control ones. This provides a rationale for using laser biostimulation as an adjuvant during orthodontic treatment to modulate tissue restructuring.