Low-level laser therapy increases interleukin-1β in gingival crevicular fluid and enhances the rate of orthodontic tooth movement.

Abstract

The aim of this investigation was to evaluate the effects of low-level laser therapy on interleukin-1β (IL-1β) levels in gingival crevicular fluid and its correlation with orthodontic tooth movement. A split-mouth design was used in 10 subjects (6 female, 4 male) aged 14 to 25years, whose maxillary first premolars were extracted. A gallium-aluminum-arsenide semiconductor diode laser (wavelength, 940nm; energy density, 8J/cm2; power output, 100mW) delivered low-level laser therapy to the experimental canine undergoing distalization at 10 points. The control canine was distalized without low-level laser therapy. The experimental and control canines were distalized using a force of 150g provided by nickel-titanium closed-coil springs. Gingival crevicular fluid was collected at 5 time points from the control and experimental sides, and the levels of IL-1β were analyzed by enzyme-linked immuno-sorbent assay (ELISA). The distal movements of the maxillary canines were measured and compared. Increased levels of IL-1β were observed in the experimental canines compared with the control canines (P<0.001). Cumulative tooth movements over an 8-week experimental period were greater for the experimental canines (occlusogram and software, 4.450 and 4.4903mm, respectively) compared with the control canines (occlusogram and software, 2.025 and 2.0501mm, respectively). A positive correlation existed between the IL-1β levels and the amounts of tooth movement across all time intervals. In combination with light orthodontic force, application of low-level laser therapy increased the levels of IL-1β in gingival crevicular fluid and accelerated orthodontic tooth movement.