The appliance used to stabilize the teeth after active orthodontic treatment is finished is called a?

The appliance used to stabilize the teeth after active orthodontic treatment is called a retainer. Retainers play a crucial role in maintaining the corrected position of the teeth to prevent them from shifting back to their original alignment. After the removal of braces or other orthodontic appliances, the teeth may still have a tendency to relapse into their previous positions due to the elastic properties of the surrounding periodontal tissues.

A retainer ensures that the teeth remain in their new, corrected positions during this critical time of stabilization. They can be either fixed or removable and are typically worn for a prescribed duration, which can vary based on individual needs.

While the other options serve important functions related to dental treatment, they do not specifically align with the role of stabilizing teeth after orthodontic treatment. A space maintainer, for instance, is used primarily in pediatric dentistry to hold space for permanent teeth until they erupt. Aligners are used during active treatment to shift teeth into their proper positions, and splints are often used to stabilize and protect teeth or jaw structures under specific conditions, but they do not serve as post-treatment stabilizers like retainers do.