Abstract: Objective: To investigate the optimal mechanical design for canines during anterior teeth intrusion with Clear Aligners. Methods: CBCT imaging data from an adult patient was selected and constructed physical models of the maxillary dental arch and invisible aligners through in vitro simulation. Nineteen sets of loads were designed based on different degrees of intrusion angles from 0 to 90 degrees. These mechanical distributions were loaded onto the models according to the maximum movement stride of the invisible aligners, and the differences in mechanical results were compared and analyzed. Results: The various parts of the canines showed different movement phenomena under different mechanical designs for the crown and root, and showed attenuation and incremental movement in different planes as the sagittal component force decreased and the vertical component force increased. Conclusion: The optimal mechanical distribution design for canines is in the range of 40 to 50 degrees for anterior teeth intrusion angle of clear aligners. However, additional design elements are required to control tooth axis and torque expression.

Key words: three-dimensional finite element analysis, clear aligners, canine mechanical design