CBCT reference planes: Median Sagittal Plane (MSP), Horizontal Plane (HP), Maxillary (FP1) and Mandibular (FP2) Frontal Planes. 
pain
ROOT RESORPTION
The primary outcome was the amount of canine retraction for six months. The amount of canine retraction was calculated as the difference between the pre-retraction and post-retraction perpendicular distances from the upper and lower canine cusp tips to the constructed FP1 and FP2, respectively. The amount of canine retraction for the six months was reported. Secondary outcomes of interest were canine tipping, rotation, root resorption and pain. Canine tipping was measured between the long axis of the canine (cusp tip to root apex) and their respective frontal planes (The outcome evaluator remeasured 10 CBCTs, to calculate the intra-observer agreement. A second investigator measured the same records, and inter-observer agreement was calculated.Patients were asked to report their level of pain USING a 100-mm Visual Analogue Scale