Effects of broad arch form wires on arch development with passive self-ligating and conventional brackets: A cone beam tomographic study

Objectives: The objective of the study is to compare the dimensional changes in the maxillary arch brought about by broad arch form CuNiTi wires between passive self-ligating brackets and conventional elastomeric ligation brackets using three-dimensional (3D) cone beam computed tomography and digital intraoral scans. Material and Methods: 60 adult patients with crowded dentition in the maxillary arch, treated on a non-extraction basis, were divided into three groups: Group I – Control group, standard arch form wires with conventional elastomeric ligation brackets, Group II – Broad Archform Copper Nickel-Titanium (CuNiTi) wires with conventional elastomeric ligation brackets, and Group III – Broad Archform CuNiTi wires with passive self-ligating brackets. Changes in alveolar bone thickness (ABT), alveolar bone height (ABH), and buccolingual inclination of teeth were compared at the start of treatment (T0) and after alignment (T1). The changes at the maxillary central incisor, premolar, and the mesio-buccal root of the first molar were evaluated. Analysis of variance and post hoc Tukey honestly significant difference tests were done to compare measurements between groups at significance levels (P < 0.05). Results: Group III showed the least reduction in ABT compared with Groups I and II (P < 0.05). ABH values increased significantly in all three groups, with the least reduction of ABH in Group III, followed by Group II and Group I. There was a significant increase in the buccolingual inclination in all three groups (P < 0.05). Conclusion: Non-extraction management of crowding using broad arch form wires produced arch expansion with both the passive self-ligating system and conventional ligation system. However, in the conventional ligation system, alleviation of crowding was accompanied by more alveolar bone loss and tipping of teeth.