When orthodontic treatment is completed, retainers are worn full-time for a few months to allow the teeth to tighten back up in their new positions. After this, the retainers are worn during sleep for many months or often indefinitely. Sometimes a small retaining wire is attached permanently to the back side of the teeth where it can’t be seen.
Specialized retainers can be used for limited orthodontic treatment, such as straightening minor irregularities of the teeth or closing small gaps.