A method, implemented with the assistance of a computer, of determining an effective orthodontic treatment comprising storing first positions of a patient's teeth, displaying the patient's teeth according to the first positions, selecting orthodontic appliances according to a proposed orthodontic treatment of the patient's teeth, storing second positions of the patient's teeth, wherein the second positions are desired positions, wherein the selected orthodontic appliances are configured to be installed on the patient's teeth in the second positions, and performing a finite element analysis to assess effects on the orthodontic appliances and on the patient's teeth based on the first and second positions and on the proposed orthodontic treatment.
