Apicale parodontitis (AP) is an inflammatory lesion surrounding the root tip of a tooth, caused by infection – under the form of microbial biofilms - of the tooth’s root canal system. This condition is mostly asymptomatic, but can result in a draining fistula, acute toothache or abscess formation. Treatment involves root canal treatment, including thorough cleaning, disinfection and sealing of the root canal system. Outcome studies however have demonstrated that healing of AP following root canal treatment is not consistent, and that non-healing is due to persistent canal infection. Therefore, there is a continuous search after improved/alternative methods to deal with infected root canals. This kind of research is initially done in in vitro studies. It is very important to use an appropriate model system in these studies, in order to mimic the complex reality of a polymicrobial and mainly anaerobic infection.

In earlier research by our group, a strictly anaerobic multispecies model system has been developed and described, both in terms of (microscopic) composition and species-specific (culture-based) quantification.

The aim of this project is to apply this multispecies model in root canals of extracted human teeth, thereby creating an optimized endodontic biofilm model system and use it to evaluate techniques for biofilm eradication from the root canal system. These techniques include laser-activated irrigation (activation of disinfecting root canal irrigants by means of a pulsed erbium laser), but also other approaches to optimize canal disinfection. In addition, the direct effect of the different methods on the endodontic biofilms is visualized by means of high-speed imaging. Concerning the latter, the required equipment and expertise is available. Finally these methods can also clinically evaluated.