An Essix retainer is used to retain the teeth in their corrected position in the same way that a Hawley retainer does, but in made from a  solid piece of clear  polyvinylchlordide (PVC) or polypropylene that is vacuum formed to fit around the patients arch.

Essix retainers, if worn 24 hours per day, do not allow the upper and lower teeth to touch because plastic covers the chewing surfaces of the teeth. Some orthodontists feel that it is important for the top and bottom chewing surfaces to meet to allow for “favorable settling” to occur. Essix retainers are less expensive, more inconspicuous, and easier to wear than Hawley retainers. However, for patients with disorders such as Bruxism, Essix retainers are prone to rapid breakage and wear.