Once an implant is placed and ready for an abutment in a cement-retained restoration, the abutment and crown are placed as two successive pieces that are cemented together. If the screw loosens or some other reason requires retorquing or removal of the abutment, the crown must either be removed, or drilled through in order to gain access. In some cases, there is not enough clearance for separate components.
A fixed detachable screw-retained crown or bridge implant restoration combines the porcelain crown and metal alloy abutment into a single piece with a screw access hole in the crown for direct attachment to the implant. Once in place, the hole in the individual crown is filled with a tooth-colored composite. This allows for a secure fit and future retrievability as needed. Screw-retained crowns and bridges are also available as layered or full contour all ceramic, with the use of a titanium base.