Integrating CBCT and virtual models for root movement with clear aligners

Clear aligners are not only a popular esthetic choice among patients, but they also facilitate better oral hygiene compared with conventional fixed orthodontic appliances. The two approaches are not yet equivalent, however, from a biomechanical point of view. While brackets and wires can provide precisely controlled tooth movements of all types in three dimensions, the ability of clear aligners to move roots to designated positions has not been confirmed. Most treatment planning for aligners considers only the crown data, not the root geometries. More complete information on tooth shapes, including both crown and root anatomies, would enhance treatment planning and provide more realistic simulations. We have developed a 3D data fusion method for creating multi-body orthodontic models from optical surface scans and CBCT images. The resulting 3D digital models combine dental structures and oral soft tissues, each from its most accurate representation: optical scanning for crowns and gingivae and CBCT imaging for roots and alveolar bone. The digital model thus provides a reliable virtual base for clinical diagnosis and 3D treatment planning.