What are tooth implants (dental implants)?

What are dental implants (osseointegrated tooth implants)?

The most common type of tooth implant (dental implant) that is placed today is the "endosseous root form implant." These objects are cylindrical or screw shaped devices that are positioned into a person's jawbone. In essence, a dental implant acts as an "artificial root" on top of which a dental crown or one end of dental bridgework can be secured.

The term "endosseous" refers to the fact that the implant is embedded in the jawbone and penetrates through the gum tissue. The term "root form" refers to the fact that this type of implant is somewhat similar in shape as the root of a natural tooth. (This isn't precisely accurate in the sense that some teeth have multiple roots.)

Root form endosseous tooth implants are also described as "osseointegrated (osteointegrated) implants." The term osseointegration refers to the fact that there is a direct fixed connection between the dental implant and living bone. (More precisely, the bone is in direct contact with an implant with no Intervening layer of connective tissue at the light microscopic level.)

A tooth implant is comprised of three components:

The dental implant fixture.

The fixture is that portion of the implant that is embedded in and becomes anchored to (osseointegrated with) the jawbone. It is that portion of the dental implant that lies below the gum line. For all practical purposes the fixture can be considered to be an "artificial root."

Implant fixtures are constructed out of titanium and typically have a hollow or solid, cylindrical or screw shaped design. Each manufacturer will utilize a proprietary surface treatment with their implant fixtures. As a result, fixture surfaces are often machined, grit-blasted, etched or plasma sprayed. The purpose of these treatments is to microscopically roughen the fixture's surface and therefore increase its total surface area, thus providing a greater amount of bone to implant contact.

The surface of a fixture may also be coated with a biocompatible, bone-regeneration material such as hydroxyapatite. The thought associated with this coating is that it may enhance the osseointegration process by allowing it to occur at a more rapid rate. The optimal overall surface preparation, however, is still a point of debate.

The dental implant abutment.

The abutment aspect of a tooth implant is its stub portion that lies at and above the gum line. The dental crown or dental bridgework that the implant supports rests on top of the implant's abutment. An abutment is usually attached to (screwed into) the implant fixture 3 to 6 months after it was initially placed.

The dental prosthesis.

The dental prosthesis refers to the dental crown or dental bridgework that the implant supports. Depending on how this dental work has been designed, it can either be cemented or screwed into place.