Abutment for Fixed Restorations
There are three main abutment types for the fabrication of fixed restorations:
– Abutments for cement retained restorations – are long, straight or angulated abutments, with or without a chamfer. Fixed restorations are cemented onto these abutments like standard crowns or bridges.
– TMA abutments for screw retained restorations – are short, conical shaped abutments. Fixed restorations that are held by screws adhering to TMA abutments.
– Abutments for direct screw retained restorations – are long sleeves with or without a pre-fabricated
metal implant connection, that are casted in the laboratory to fabricate restorations that are held by screws adhering directly to implants.
Note: Provisional abutments are available for screw retained restoration types. They share the main characteristics of the corresponding final abutments.
Basic Abutment Type Comparison Table:
|Cement retained abutments||TMA abutments||Direct, screw retained abutments|
|Description||Long, straight or angulated abutments, with or without a chamfer||Short, conical, straight or angulated abutments||Long, straight abutments, with or without a pre-fabricated metal implant connection|
|Angulated abutment options||*15°, 25°, 35°||*17°, 30°, 45°||None|
|Available gingival heights||
(Straight TMAs only)
|Main benefits||Most similar to standard crown and bridge procedures
Can be modified chairside or in the dental laboratory
|Retrievable||Low vertical height|
|Concerns||Abutment restorative portion should not be shorter than 4 mm||Access holes through occlusal surfaces||Access holes through occlusal surfaces
May overload implant connection
*Not available in all platforms