The nance is a holding appliance used to maintain space in the upper arch as baby teeth are lost. It has two metal bands that are cemented to the first molars to keep them from moving forward until the other permanent teeth have erupted. An acrylic button rests in a section of the palate and is attached to the bands with a wire.
The lip bumper is a holding appliance for the lower arch. It prevents the back molars from moving forward, reserving space to allow the rest of the permanent teeth to erupt in their correct positions. It also can create more space in the lower arch, helping to alleviate crowding. The lip bumper is a thick, custom-bent wire that rests between the teeth and lower lip and is held in place by bands that are cemented to the molars.