Active self-ligating brackets use a spring clip or similar mechanism that presses against the arch wire. Passive self-ligating brackets use a slide or door that closes over the slot without exerting the same active pressure on the wire. This structural difference is the main reason their clinical behavior is not identical.

Evidence does not support a universal winner for total treatment time. A systematic review and meta-analysis found no significant overall difference in treatment time, number of appointments, or initial discomfort when self-ligating systems were compared with conventional brackets. Another review comparing active and passive designs concluded that differences in efficiency are case-dependent rather than absolute.