Comparison of the anterior limit of the dentition in patients treated with self-ligating straight-wire, conventional straight-wire and standard edgewise appliances.

The aim of this study was to identify and compare any differences in the position of the anterior limit of the dentition provoked by three different types of orthodontic mechanics: traditional edgewise, straightwire and self-ligating. A sample of 54 patients (selected from a group of 289 patients) possessed a range of Little’s Irregularity Index values for the upper and lower dental arches between a minimum of 6.5 and a maximum of 13.5 at T0, and corresponding final values no greater than 2 and hence of minimal irregularity. The 54 patients were subdivided into three groups according to the type of brackets used in their treatment: Group 1 was composed of 24 patients treated using the self-ligating technique, Group 2 of 15 patients treated using a conventional straight- wire technique (Roth) and Group 3 of 15 patients treated using the standard edgewise technique. Cephalometric tracings were performed on laterolateral teleradiography. Group 1 value was found to be nonsignificant, whereas significant labial inclination was noted in Groups 2 and 3 (P < 0.05). A significant labial inclination of the upper incisors was also evidenced in all three sample groups.