Investigation of the torque values of different archwires used with three passive self-ligating brackets placed at different incisor inclinations and heights by finite element analysis

This study comprehensively evaluates, through finite element analysis, the torque moment, Von Mises stress, and displacement values generated by three different passive self-ligating bracket systems (Pitts21 PRO, Damon Ultima, and Carriere SLX 3D) at various bracket placement heights (5–8 mm), incisor inclinations (0°–20°), and with two different archwire materials (SS and TMA). The findings demonstrate that bracket design and slot geometry play a decisive role in torque transmission; Carriere SLX 3D produced the highest moment values, Damon Ultima generated the lowest, and Pitts21 PRO exhibited an intermediate moment behavior among the systems. As bracket height increased, torque also increased across all systems; however, the rate and pattern of this increase varied depending on bracket design. Increasing inclination resulted in reduced moment values for all brackets, with Carriere SLX 3D showing the greatest sensitivity to this change and Pitts21 PRO presenting the least variation. Comparison of wire materials revealed that SS archwires produced approximately twice the torque, stress, and displacement observed with TMA wires, thereby creating significantly higher biomechanical loads. Von Mises stress distributions and displacement patterns were consistent with the moment outcomes, confirming that Carriere SLX 3D exhibited the highest stress profile, whereas Damon Ultima displayed the lowest. This study has demonstrated the decisive effects of bracket design, placement height, archwire material, and initial inclination on torque control, thereby providing a comprehensive perspective for case-specific bracket selection, positioning, and the planning of orthodontic treatment mechanics.