A method for applying orthodontic forces to one or more teeth using a single model of the tooth or teeth which are to be moved. The model chosen is the final corrected configuration for the patient as determined by their oral health care provider and comprises the final position and orientation of the tooth or teeth to be achieved after a successful treatment regimen. A series of aligners are made which each comprise the corrected configuration. Each successive aligner in the series is comprised of a selectively stiffer material than the previous aligner in order to move the tooth or teeth into the final desired position. As the patients treatment progresses, the patient receives the next successive aligner which is incrementally more rigid or stiff than the previous aligner, thus effectuating the movement of the tooth or teeth to their desired final position and orientation.
