Blue-light emitting diode exposure effect on alkaline phosphatase levels post-orthodontic stabilization in rats

Introduction and Aim: Exposure to blue light-emitting diode (blue-LED) during the stabilization period can prevent relapse by increasing the tension side osteoblast, which is characterized by increased levels of alkaline phosphatase (ALP) in the gingival crevicular fluid (GCF). Increasing ALP levels occurred from day 7 with the highest peak on day 14 post-stabilization. The purpose of this research was to analyze the effect of blue-LED exposure during the stabilization period on ALP levels in the tension side GCF of Wistar rats (Rattus norvegicus) at days 0, 3, 7, and 14 post-stabilizations.   Materials and Methods: Ten male Wistar rats aged 2.5-3 months, weighing 200-250 grams were divided into two groups (control and LED group). An orthodontic force of 35 grams was applied to the mandibular inter incisors of Wistar rats using an open coil spring. Blue-LED (490 nm wavelength, 1000 mW/cm² light intensity) exposure for 30 seconds once a day during a 7-day stabilization period. Gingival crevicular fluid was taken with paper points on days 0, 3, 7, and 14 post-stabilizations for ALP levels measurement using an ELISA method. Two-way ANOVA and Post Hoc LSD statistical tests were performed.   Results: The results showed LED group ALP levels were higher than the control group. There has been a significant increase in ALP levels on days 7 and 14 in the control and LED groups.   Conclusion: It was concluded that blue-LED exposure increased tension side ALP levels. Increasing ALP levels occurred from day 7 with the highest peak level on day 14. Blue-LED exposure in the stabilization period is a favorable therapeutic option to accelerate alveolar bone formation due to being non-invasive, easy to apply clinically, and low cost.