Three-dimensional diagnosis andorthodontic treatment of complex malocclusions with the invisalign appliance

Abstract Recent developments in software technology have made it possible to create a virtual three-dimensional (3D) model of the dental arches from digitally scanned impressions of a patient's dentition. This model may then be manipulated with software to produce stages of tooth movement from the initial malocclusion to the final desired occlusion. A stereolithographic model is made for each stage of tooth movement which is the basis for construction of a series of clear, thin, overlay appliances. These appliances are worn full time by the patient to move the teeth according to the programmed stages of movement. Malocclusions involving mild to moderate crowding and space closure have been proven to be successfully treated with this appliance. The present study shows orthodontic treatment of patients with more complex orthodontic problems, requiring dental expansion, Class II and Class III correction, extraction treatment and correction of overbite. Experience with this appliance, thus far, has demonstrated excellent patient compliance with less discomfort, and improved esthetics and oral hygiene, when compared with fixed orthodontic appliances. Orthodontic treatment with this appliance is a potentially useful alternative approach to fixed appliances for treatment of a variety of malocclusions in patients with fully erupted permanent teeth.