Efficacy of Diode Laser Therapy in Acceleration of Orthodontic Space Closure: A Split-Mouth Randomized Clinical Trial

Purpose: To test the null-hypothesis of no significant difference in velocity of space closure of extraction in sectors undergoing laser bio stimulation and those that were not exposed. Methods: Using an incomplete block split-mouth design, the quadrants of twenty patients requiring extraction of first premolars were randomly assigned to an intervention (laser exposure) and a control (non-exposure to laser) group. Space closure and tooth movement were achieved reciprocally by using a lace-back force system between anterior and posterior teeth, assessed with digital caliper. The experimental side was subject to infrared radiation from a semiconductor (aluminium gallium arsenide) diode laser with a wavelength of 940 nm on days 0,7, and 14 in the first month, and thereafter on every 15th day until complete canine retraction was achieved on the experimental side. Results: An average increase of 30% in the rate of tooth movement was observed with the low-intensity laser therapy compared with the control sides. Gap closing speed between intervention and control sides were significantly different following day 14. Conclusion: The null-hypothesis was rejected. Low-intensity laser therapy with the settings used here is considered as a valid complementary option to accelerate orthodontic space closure.