Intra-oral degradation of resin-based dental materials

Resin-based dental materials are used in all disciplines in dentistry, and have many advantages. Beside their esthetic properties (tooth-colored), they can be glued to remaining tooth tissue. This tooth-sparing approach is much less invasive than previous (metal) restorations, and it is generally recognized that this will aid in maintaining teeth as long as possible in good conditions. Unfortunately, resin-based materials undergo degradation in the oral environment, where they are not only exposed to chemical, thermal and mechanical challenges, but also to oral bacteria and the biofilm. Secondary caries – i.e. new caries along an existing filling – is the most common reason for failure of composites, today’s standard filling material with resin matrix. However, the mechanisms of degradation, especially bacterial degradation, are not yet fully understood. The objective of the proposed research is to determine to which extent microbial interactions play a role in the degradation process and in secondary caries development. Both commercial and experimental composites will be evaluated. The role of early colonizers (= first oral species attaching to the tooth and restoration) will also be evaluated using a very innovative bio-atomic force protocol using a socalled ‘single-cell probe’. Focus will be on development of resin-based materials more resistant to bacterial degradation.