Abstract: With the continuous improvement of living quality, the general public is not satisfied with just aligned and healthy teeth but also in search of a more pleasure and comfortable way to align teeth. This trend is more obvious in adults who seek orthodontic treatment. They view orthodontics with clear aligner as their preferred choice. When comparing with the classic brackets and wire treatment method, clear aligners employ a series of transparent and self-removable plastic aligners to align teeth and treat malocclusion. However, in the treatment process, there is a lag between the intended amount of teeth movement and the amount actually delivered, which causes a treatment efficacy issue. In order to facilitate the patient selection and the design of treatment involving clear aligners, this article reviews literatures concerning the efficacy of Invisalign when used to deliver a series of tooth movement including extrusion, intrusion, rotation, tipping movement ,expansion arch and molar distalization.

Key words: Orthodontics, Invisalign, clear aligner, efficacy