Panel A shows anatomical facial landmarks used to determine border of retainer: A, rhinion; B, margo infraorbitalis; C, processus temporalis ossis zygomatici; D, vertical line at angulus oris plane; E, angulus oris. Panel B shows CAD of retainer merged on 3D face scan. Panel C shows CAD of retainer merged on 3D face scan with mask. CAD, computer aided design.</p