It is intended to evaluate changes in arch dimensions and incisor inclination as well as changes in the WALA Ridge in no extraction patients treated with interactive self-ligating brackets (Empower®) and passive (Carriere SLX®) at the end of the phase of alignment and leveling. For this, study models and profile radiographs taken before the start of treatment and at the end of the alignment and leveling phase will be evaluated. The parameters to be measured are: intercanine distance, arch depth, upper and lower incisor inclination, and WALA ridge analysis

Inclusion Criteria:

• Complete permanent dentition, except third molars.
• Class I malocclusion, determined by Angle ANB 2 plus or minus 2
• Visible alveolar teeth and ridges in plaster models, the latter being compatible and checked against the morphology of the WALA Ridge clinically presented by the patient.
• Little index with minimum Irregularity 4-6 mm.
• Patients with x-rays of initial profile and at the end of alignment and leveling in good condition.

Exclusion Criteria:

• Models in poor condition that do not allow measurements.
• Patients who do not wish to participate in the study
• Patients with cleft lip and palate
• Patients with craniofacial anomalies
• Patients with previous orthodontic treatment