This article gives an overview of generally accepted and special concepts of the last and often life-long treatment-phase in adult orthodontics, the retention phase. The secret of successful adult orthodontics lies in adult-specific principles of histology and physiology and the interrelation of joint, occlusion, and muscles, which helps define the requirements of proper diagnosis, mechanics, and retention. Retention in adults should include maintenance of tooth position, overall dental health, and a periodontal status that can be attained by combinations of several retention concepts: retention appliances and surgical and restorative retention procedures. Short- and long-term postretention follow-up studies have shown that there is no guarantee for long-life stability after orthodontic tooth movements in adults without an anomaly- and treatment--specific retention phase.
