Dental Implant Body12 Nov, 2015
Dental Implant Body
This term describes the component placed in the bone, which is sometimes also referred to as an implant, fixture or implant fixture. Occasionally, the term is used colloquially to describe both the endosseous component and those parts placed immediately on top. The preferred term for the endosseous component is 'dental implant body', or 'implant body' where its application is clear from the context.
The majority of dental implants are designed to be placed into holes drilled in the bone and are thus axisymmetric. Many are screw shaped, since this aids in primary stability, and are inserted into tapped holes. Where bone has a low density this may result in poor stability and thus some designs incorporate selftapping features to overcome this problem. Others are made with a tapering design, which creates a wedging effect as the implant body is seated.
In addition to screw threads, other surface features may be included with the intention of enhancing OI. Typical of these are macro surface irregularities, and porous metallic and ceramic coatings, typically of hydroxyapatite. These features usually also enhance retention, which is important since an osseointegrated smooth titanium surface has a low shear strength.
The implant may either be of a multi-part design, which is intended to be buried while OI occurs, or a single-part design, which will penetrate the mucosa from the time of placement. Multi-part designs incorporate various mechanical linkages to facilitate the joining of the different components and the mechanical integrity of the joint. These usually include a hexagonal socket on one component to provide resistance to rotation, or a tapered joint to provide both this and a seal. The joint is commonly held closed by a screw, although some manufacturers employ cement fixation. Following placement of a buried implant, it is usual to insert a cover screw in its central hole to prevent tissue ingress and bone growth over the top of the implant body.
Implant treatment is but one of a range of procedures available to the restorative dentist to help the partially dentate or totally edentulous patient. Its use must be set within a comprehensive assessment of patients' needs and the most suitable method of helping them. Treatment with dental implants does not in itself negate the need for care in patient assessment, treatment planning and provision, and cannot overcome neglect of basic principles or the use of inferior techniques. It is subject to the normal constraints on restorative and minor surgical procedures imposed by systemic conditions. In addition, there is a range of conditions that are associated with or thought to be associated with increased risk of implant failure.