Digital Workflow for 3D Design and Additive Manufacturing of a New Miniscrew-Supported Appliance for Orthodontic Tooth Movement

Abstract

The introduction of digital workflows and their combination with miniscrew assisted appliances has opened new and enthusiastic perspectives in modern orthodontics. However, in all digital workflows currently in use for orthodontic tooth movement, the miniscrews are inserted first in the maxillary bone, often by means of a surgical guide, and then the appliance is fabricated and secured over the miniscrews with different fixation mechanisms. By doing so, some adaptation problems can be encountered while securing the appliance over the miniscrews, and the chairside time required can therefore be significant. In the present study, we introduce a digital workflow for the design and fabrication of a new appliance, customized on the individual morphology of maxillary bone by using patient Cone Beam Computed Tomography CBCT, for sagittal and vertical orthodontic tooth movement (DIVA, divergent anchors). Differently from the existing protocols, the appliance is cemented first intraorally, serving as a surgical guide for the subsequent insertion of miniscrews. In this way, the adaptation problems are avoided and the chair-side time is reduced.