Typically, dental implants take the form of a false tooth with a titanium screw extending out the bottom. That screw goes into the bone, permanently holding the tooth in place. The problem is, bacterial biofilms can form on it soon after implantation, causing infections. One approach to this problem has been to apply an antibacterial coating to the screw. Now, however, scientists at Belgium's University of Leuven have developed an implant that disperses an antimicrobial solution from the inside out.
The screw section of the new implant is made from a porous titanium-silica composite, that has a reservoir running vertically down the inside (see the diagram below). That reservoir gets filled with a germ-killing solution, then a cap is placed at the top of the reservoir, and finally the false tooth is mounted on top of the screw.
Once the whole thing has been screwed into the bone, the solution will begin to slowly diffuse out, keeping biofilms from forming at the screw/bone interface. The idea is that by the time there's no more of the liquid left, the implant will have been integrated into the surrounding bone, so infections won't be an issue.
In lab tests, the implant was filled with an antimicrobial mouthwash known as chlorhexidine. As it was dispersed, not only did the liquid stop Streptococcus mutans biofilms from forming, but it also killed ones that had been grown on the implant beforehand.
A paper on the research was recently published in the journal European Cells & Materials.
Source: KU Leuven