A self-ligating bracket is a ligature-less system with a mechanical device built in to close off the edgewise slot. Secure engagement may be produced by a built-in clip mechanism replacing the stainless steel or elastomeric ligature. Both active and passive self-ligating brackets have been manufactured, referring to the bracket/archwire interaction. Every self-ligating bracket, whether active or passive, uses the movable fourth wall of the bracket to convert the slot into a tube. Numerous studies have demonstrated a dramatic decrease in friction for self-ligating brackets, compared to conventional bracket designs.