“…However, their registration is often impeded by the limited availability of anatomic landmarks [ 8 , 14 , 15 , 16 ]. Many approaches have been proposed to compensate for these limitations [ 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. Examples include multi-staged or indirect workflows, while direct digital prosthetic workflow may require auxiliary scanning guides, fiducial markers, or pins as anatomic references to facilitate the scan registration.…”