In 1997, adult patients were given a new choice, “invisible braces,” in lieu of the traditional bracket and arch wire techniques. With the use of a series of retainers, teeth can be moved in minute increments, solving some patient challenges. However, not all cosmetic cases can be resolved using this technique. Results are achievable in the following cases: minor tooth movement, deep overbites correctable by advancement of the incisors, arch expansion achieved by some tipping of the teeth, and treating of relapse after use of a fixed appliance. It is not successful for treating the following: some skeletal discrepancies, rotated teeth, open bites requiring closure, arches with several missing teeth, and with bicuspid extractions, as the aligners cannot keep teeth upright for space closure. Treatment preparation requires an initial assessment, diagnosis, treatment planning, and pretreatment records (ie, Panorex, cephalometric radiographs, bite registration, photographs, and polyvinyl siloxane impressions). Since all aligners are created at the beginning, treatment plans cannot be changed. The time frame for creation and delivery of the appliances can be as long as 2 months. Also, the patient must be ready to wear the appliances as many as 22 hours a day. Appliances can be removed only to eat, drink hot liquids (to avoid warping), and liquids that could stain the material, and for brushing/flossing. Careful case selection can result in successful outcomes; however, there are cases where fixed appliances produce more predictable and manageable results.
(Source: Dental Abstracts, 2008, Volume 53, Issue 2)
