Without the implant's internal bevel and the long, tapered hex of Sulzer Dental's abutment, the Friatec connection has as much rotational instability as the standard external hex. Friatec's straight and angled abutments for cemented restorations have premachined margins that are anatomically incorrect. Abutments feature a premachined shoulder that complicates impressions. The shoulder on angled abutments is higher on the labial than on the lingual, unlike a preparation on a natural tooth. While the flashings may initially reduce rotational movements, they cannot eliminate tipping, as there is no contact on the vertical walls.
Functional movements can ultimately flatten the metal flashings and result in abutment rotation.
Such rotational and tipping instability has been reported to be a contributing factor in screw loosening.