Holder:
Retention is a measure to consolidate the curative effect of orthodontic treatment and keep the teeth in an ideal aesthetic and functional position, which is called retention. At this time, it is called a retainer. After orthodontics, after the appliance is taken out, because the teeth are still unstable in the new position, it is often necessary to wear retainers to keep the new position of the teeth on the alveolar bone and wait for the reconstruction of the alveolar bone.