Increased interpremolar development with self-ligating orthodontics. A prospective randomized clinical trial.

In compressed dental arches with mild to moderate crowding, space can be gained during the alignment phase to help improve tooth location. The aim of this study was to compare transverse measurements before and after the alignment stage in two groups: Group A treated with passive selfligating brackets, (Damon System) and Group B with conventional brackets (Roth philosophy). The change in transverse diameter between teeth was measured on dental casts taken before and after orthodontic alignment. Twenty four patients of both sexes aged 13 to 36 years, with moderate tooth crowding (4 to 6 mm), were treated. They all received treatment at the Department of Orthodontics, School of Dentistry, University of Buenos Aires. Patients were distributed randomly into two groups of 12. No extraction was performed until the end of the alignment. Dental casts were measured before and after alignment. The distance between upper first premolars increased more in Group B (p = 0.008), and the distance between canines was higher in Group B, with statistically significant difference (p < 0.01). Both systems enable tooth alignment by increasing transverse diameter of the arches in patients with mild to moderate crowding. The greatest transversal development occurs in the interpremolar area in both techniques and is significantly higher with selfligating orthodontics. Intercanine distance increases significantly with conventional orthodontics compared to selfligating orthodontics.