After the active orthodontic treatment period is complete and your braces have been removed, you will be given a retainer for each arch. This marks the beginning of the retention phase, during which a retainer is used to hold teeth in their new positions while the jawbone, gums and muscles adapt. You must wear the retainers as instructed, otherwise your teeth may revert to their former positions, and the benefits of having had braces will be lost. Retainers need to be adjusted regularly, so make sure to bring them with you to your retainer check appointments.