The Dental Implant consists of four components:
1. The implant fixture.
2. Cover screw.
4. Abutment screw.
The dental implant fixture is the component which is surgically placed into the jawbone. The cover screw is screwed into the top of of the fixture to prevent downgrowth of soft and hard tissue into the internal, threaded area. The abutment is the transmucosal component which is conneted using an abutment screw into the fixture.
The implant fixture is made of pure titanium with machined threads on the outer surface as well as the inner channel. The fixture is threaded into the jawbone using a series of surgical procedures to achieve an intimate contact between the dental implant fixture and bone. The top of the fixture has usually a hexagonal design and threads are visible in the internal channel.
The cover screw acts as a seal on the coronal portion of the fixture and fits into threads of the internal channel over the hexagonal shape. Cover screw is used during the healing period after first surgical procedure. It has a groove for screwdriver access and is rounded on top to help prevent damage to soft tisuue.
The abutment is usually made of titanium. The apical portion has a recessed hexagonal shape designed to fit the coronal portion of the implant fixture. Abutments can also be made from Zirconia. Zirconia abutments provide a light colored base for an esthetic all ceramic restoration.
The abutment screw inserts through the abutment and threads into the fixture to connect the two components.
Different implant brands have added components. They develop new features for each component to simplify the implant procedure. Surface treatments are also done in the implant fixture to enhance healing and osseointegration. These techniques and technologies have a bearing on the overall dental implants cost.
Jesus Lecitona+, DMD, MScD-Prosthodontics