For the evaluation of the canines and molar displacement, two CBCT will be required: the first one before the beginning of the traction (T0), the second one after three months (T1). Both the CBCT will be imported in the MIMICS image processing software (Materialize Group, Leuven, Belgium). Limiting the tissue density ranges and restricting the anatomical area of interest, a cropped colored mask will be obtained from each CBCT. Then the co-registration, through the identification of 5 at least landmark points, will allow the overlap of the two masks. At this point, calculating the 3D surface models, the tooth pre- and post-treatment positions will be evident and the measurement of the displacement possible.