The Effect Of Low-Level Laser Therapy On The Rate Of Tooth Movement During Maxillary Canine Retraction; A Randomized Clinical Trial

Abstract

The aim of this trial was to evaluate the effect of low level laser therapy on the rate of tooth movement during maxillary canine retraction. So the primary outcome measured was the maxillary canine distance travelled per time with and without laser application on the dental models. Also, laser and control sides were compared in the amount of anchorage loss, maxillary canine tip, torque, rotation and root resorption, and maxillary first molar tip during canine retraction. The sample was recruited from the out patients’ clinic of the Orthodontic Department. Faculty of Dentistry, Ain-Shams University. 15 adult female patients with indication for maxillary first premolar extraction and canine retraction were recruited to this split-mouth randomized controlled trial. All the patients were randomly allocated to either right side experimental (receive laser application) or control groups, the left sides were assigned to the alternative intervention. Three patients were lost to follow up. After placement of fixed orthodontic appliance, leveling and alignment till 16x22 mil stainless steel arch wire, CBCT imaging and first premolar extraction, the maxillary first molar and the maxillary second premolar were ligated together and designated as the anchorage teeth and then canine retraction was done using NiTi coil spring between the canine bracket and molar band hooks delivering 150 gm of force. Soft laser used with active medium InGaAs (Indium gallium arsenide) semi-conductor diode applied using a laser machine (biolase epic x console) having a wavelength of 940 + 10 nm. Power was adjusted to 2.5 watt and the time was 30 seconds. These parameters yielded an application dose of 72J for each session. Laser was applied buccally only at the level of the middle third of the canine root at days 0,3,7 and 14 and at 1 month then every two weeks until complete canine retraction on one side. Alginate impressions were made every 4 weeks to produce a series of dental models to assess the rate of maxillary canine retraction. At the end of the trial another CBCT images were ordered.