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In dentistry, an abutment is a connecting element. This is used in the context of a fixed bridge (the "abutment teeth" referring to the teeth supporting the bridge), partial removable dentures (the "abutment teeth" referring to the teeth supporting the partial) and in implants (used to attach a crown, bridge, or removable denture to the dental implant fixture. The implant fixture is the screw-like component that is Osseointegrated.
Bridge abutments are made such that the path of insertion of the teeth involved is nearly parallel with each other.
Partial denture abutments
Partial denture abutments are unique in that they may incorporate elements such as rest seats, guide planes, and recontouring.
These are usually called prosthetic implant abutments. These abutments can be made from a variety of materials, such as titanium, surgical stainless steel and gold. More modern abutments are now also made from zirconia, which is a white ceramic, to better complement the aesthetics of a dental implant restoration. The two images to the right show a ceramic abutment and the ceramic crown bonded to it.Prosthetic abutments are connected to the dental implants via a screw. This screw needs to be tightened to a predetermined torque, in order to avoid screw loosening during chewing, which can often create a counter-clockwise torque on the implant-abutment interface, encouraging the abutment screw to come loose. This can largely be prevented with proper screw design and torquing of the abutment.
The images to the right show how a ceramic abutment can enhance a ceramic crown by giving it a more lifelike appearance. Ceramic abutments have to be used with care, however, since their compressive strength is nowhere near that of titanium, gold or other noble metals. Most clinicians feel more comfortable using a metal prosthetic abutment in the posterior molar areas, due to the increased masticatory forces present in these areas.
An abutment is not necessarily parallel to the long axis of the implant. It is utilized when the implant is at a different inclination in relation to the proposed prosthesis.