This study aims to examine the play between various archwires and bracket systems, exploring potential variations in angle values for specific torque and torque values for a given angle along different bracket systems. Therefore, seven brackets systems were evaluated in conjunction with different stainless steel archwires of varying dimensions (0.016 '' x 0.022 '', 0.018 '' x 0.025 '', and 0.019 '' x 0.025 ''). Biomechanical behavior during torque development and transmission was assessed using a six-component force/torque sensor. Torque angles (5-45 degrees) were specified with subsequent torque measurement, and the sequence was reversed by setting the torque (5-30 Nmm) and measuring the angle. A reference measurement with 0 Nmm torque served to evaluate bracket slot play. Bracket play (0 Nmm) during palatal load ranged between 20.06 degrees and 32.50 degrees for 0.016 '' x 0.022 '' wire, 12.83 degrees and 21.11 degrees for 0.018 '' x 0.025 '' wire, and 8.39 degrees and 18.73 degrees for 0.019 '' x 0.025 '' wire. The BioQuick (R) bracket exhibited the highest play, while Wave SL (R) and Damon (R) Q brackets demonstrated the lowest play (p < 0.001). Significant differences (p < 0.001) between the brackets were observed in the torque angles required to achieve torques of 5-20 Nmm. In summary, each bracket system has a different torque transmission, which is of great clinical importance in order to achieve correct torque transmission and avoid complications such as root resorption.
