Bioreactors: How to Study Biofilms In Vitro

The interactions taking place between a dental (bio)material, the surrounding tissues of the host, and the biofilm that grows to permanently colonize this microenvironment are amazingly complex when analyzed in detail yet contribute to a crucial factor: the balance between health and disease conditions. From a microbiological point of view, this has a dramatic impact on the longevity of dental treatments. Researchers have long since tried to recreate, even if in parts, this complexity on a bench, both using a reductionistic approach as often performed in research and, more recently, by trying to create models approaching the most realistic behavior. These efforts yielded a wide range of bioreactor systems currently available. We hope that in a future not too far, bioreactor models will be able to reliably reproduce most clinical conditions, dramatically reducing the need for animal and clinical studies. Unfortunately, a universal bioreactor able to mimic any clinical situation still does not exist. Each model comes entwined with its advantages and limitations that must be acknowledged when choosing which model best fits a distinct experimental design. This situation, together with a reduced overall level of standardization, makes the comparison of the obtained results very difficult. This chapter presents an overview of the microbial communities and the bioreactor models that are most significant for studying the microbiological performances of dental materials.