Gender-related response to different wavelength low-level laser therapy in orthodontic mandibular canine movement: a split mouth study
https://doi.org/10.36377/ET-0159
Abstract
INTRODUCTION. Low-level laser therapy (LLLT), known as photobiomodulation (PBM), has recently attracted the attention of clinicians to speed up orthodontic tooth movement. Nevertheless, the sex-related effects of LLLT have not been investigated yet, although the role of sex hormones on bone remodeling has already been reported. The objective of this study was to determine if LLLT preferentially accelerates the rate of mandibular canine retraction in men or women.
MATERIALS AND METHODS. Twenty systemically healthy patients (10 male, 10 females; age range from 18 to 25 years) who were undergoing fixed orthodontic treatment were included in a split-mouth randomized control trial. Subjects were stratified into two groups: Group 1 (n = 10) was treated with 650 nm LLLT on the experimental side, while group 2 (n = 10) was treated with 976 nm LLLT. Opposite sides of the animals were used as a sham-irradiated control. PBM parameters were compatible (8 J/cm2 energy density, 0.26 W/cm2 power density) and administered on d 0, 3, 7, 14, then bi-weekly thereafter. Retraction of canine was done with 150 g force produced by elastics. Amount of linear tooth movement was evaluated at 1 month and space closure duration was monitored until complete closure.
RESULTS. The amount of the canine movement was significantly higher on LLLT treated sides compared to control ones after 1 month (p < 0.001, mean difference: 0.92 ± 0.46 mm; 1.44 ± 0.29 mm vs control sides, respectively). Better acceleration was obtained at 976 nm (1.12 ± 0.44 mm gain) vs. 650 nm (0.71 ± 0.39 mm; p < 0.001). LLLT sides closed spaces in 3.3 months, whereas controls took 6.2 months for complete closure. Sex stratification found that the accelerations were consistently higher in waves for both males and females indicating no sex-by-wavelength interactions.
CONCLUSIONS. LLLT efficiently speeds up the retraction of the mandibular canine, and the 976 nm wavelength works best. Sex does not affect the effectiveness of LLLT, which supports the consistent use of similar procedures across different groups of patients.
About the Author
A. Alhumadi
University of Kufa
Iraq
Competing Interests:
Iraq
Almustafa Alhumadi – Department of Pediatric, Orthodontics & Preventive Dentistry, College of Dentistry
Najaf, Iraq
Competing Interests:
The authors report no conflict of interest.
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Review
For citations:
Alhumadi A. Gender-related response to different wavelength low-level laser therapy in orthodontic mandibular canine movement: a split mouth study. Endodontics Today. 2026;24(1):58-66. https://doi.org/10.36377/ET-0159
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