Computer-assisted treatment planning and analysis.

The Invisalign orthodontic system (Align Technology, Inc, Santa Clara, CA) is a series of clear removable appliances that is worn by a patient to correct malocclusions. Introduced in 1999, it has been applied to successfully correct an increasingly wide variety of malocclusions. Part of the success of the system is because of the innovative technologies inherent in the design of the appliances. During the development of the system, many challenges and issues needed to be overcome to realize the product. Many of these issues were not specific to Invisalign, and represented general problems in the area of computer-aided orthodontics. The general problems of developing a virtual model of a patient's dentition appropriate for use in orthodontics, performing a treatment plan on a virtual dentition model, and analyzing how accurately the virtual treatment plan executed in the patient's mouth are presented.