How Low-Level Laser Therapy Affects Tooth Movement, Root Health, and Pain During Braces Treatment

Low-Level Laser Therapy Protocol: • The intrusion appliance will be cemented with a Multi Cure Glass Ionomer cement (3M Unitek, Monrovia, Calif) on the maxillary first molars. Each upper 1st premolar tooth and occlusal cap will have a Victory bracket with a 0.022” slot bonded on the buccal and palatal surface (3M Unitek) with an indirect bonding technique. • Two beta-titanium-molybdenum alloy 0.017 x 0.025-in cantilever springs (3M Unitek) will then be bent extraorally. The springs will be calibrated to deliver 10 grams of intrusive force each (20g per tooth). These springs were used to deliver the required apical force and were calibrated to the nearest gram with a strain gauge (Dentaurum, Ispringen, Germany). • The preformed cantilever springs were transferred intraorally and recalibrated according to the appropriate force required. The springs were double-ligated with ligature wires and an elastomeric ring to ensure full bracket engagement and continuous force application. • The intrusion of the maxillary first premolar teeth will take place from day 0 to day 56 (eight weeks). Day 0 is the start of the intrusion appliance being cemented and coincides with the same appointment as the 1st laser application day. The springs will be calibrated at day 28. (same appointment as the 3rd laser application) • The co-investigator will apply the LLLT on days 0, 14, 28 and 42 with either the sham or true laser. An 810-nm Galium Aluminium Arsenide diode laser (Pioon S1, Wuhan Pioon Technology.co.Ltd, China) will be utilised in this study. The laser energy will be delivered via a 400µm diameter tip. A continuous laser mode with an average power output of 0.18W will be used. The laser unit will be calibrated before use. • The laser tip will be held perpendicularly contacting the gingival mucosa during the laser irradiation. The irradiation time will be 15 seconds per point. There will be 6 applications points on the buccal and 6 applications points on the palatal surface. There will be 3 minutes of true laser application per patient. (3 minutes true and 3 minutes sham laser) • All relevant safety protocols for the application of the laser will be followed. This includes laser safety training for the operator, assistant and patient, laser safety glasses for all patients and staff, high volume evacuation and standard PPE for a dental setting. The laser application will take place in a controlled treatment area with appropriate signage and setup. • The upper right and left 1st premolars will be extracted after 56 days since initial laser application (14 days since the last laser application) and the appliance removed afterwards • Patient adherence to the appointments, protocol and breakages of the appliance will be recorded in the patient's medical record. • Following completion of the study, participants will continue their comprehensive orthodontic treatment within the Department of Orthodontics until treatment completion.