Prof. Marco Maiolino
Full arch restorations can be fabricated with metal frameworks layered with acrylic, metal ceramics or more lately zirconia that can be monolithic or layered with feldspathic porcelain. The esthetics and durability of acrylic prostheses are not optimal leaving the restorations layered with ceramic or largely ceramic to choose from. Metal ceramic restorations are more often fabricated in segments to facilitate porcelain application and fit of the restorations to implants. When the restorations are segmented the restoration can have the discrete segments removed and repaired should there be issues of porcelain breakage. With implant supported restorations, porcelain fracture or chipping is a common and difficult problem to manage this is more so with large restorative structures. The use of monolithic zirconia restorations for these large reconstructions eliminates the use of feldspathic porcelains, allows the restoration to be fabricated in one piece and allows a well-fitting restoration as distortion is compensated for by luting of the bases into the restoration on a verified master cast. The use of full arch restorations also allows fewer implants to be placed due to splinting across the arch that results in a biomechanically advantageous loading pattern for the retaining screws and the implants.
The ability to alter the position of the screw access reduces the need for grafting procedures and eliminates the use of cement to retain the restorations. The combination of being able to re direct screw access relative to the axis of an implant together with the ability to use CAD/CAM to manufacture monolithic Zirconia restorations are a solution for the most common complications when implant supported restorations are provided.