Osseointegration--the influence of implant surface.

The modification of implant surfaces from the original machined to 'micro-rough', and more recently 'bioactive', surfaces has been proposed to improve clinical outcomes. This review outlines the evidence for the superior performance of modified implant surfaces. Pre-clinical trials consistently show that modified implant surfaces are more osteogenic and improve the degree of osseointegration. Clinically, there is a clear trend for improved clinical success with 'micro-rough' compared with machined implants. This is particularly the case in compromised sites, such as the posterior maxilla, and compromised patients, such as smokers. Furthermore, 'micro-rough' implant surfaces perform better in augmented sites, and facilitate the more predictable use of short implants, thus reducing the need for more invasive augmentation procedures. 'Micro-rough' implants have been associated with an increased susceptibility to peri-implantitis, but these findings relate to a surface that is no longer manufactured. Newly developed 'bioactive' surfaces have only been evaluated in a limited number of clinical studies.