Recent Advances in Studies of Polymicrobial Interactions in Oral Biofilms

The oral cavity supports a complex and finely balanced consortium of microbial species, many of which cooperate within structured biofilms. These communities develop through multitudinous synergistic and antagonistic interspecies relationships. Changes in the dynamics of oral microbial populations are associated with the transition from healthy teeth and gums to dental caries, gingivitis and periodontitis. Understanding the ecology of oral biofilm communities, and how different species communicate within a given host, will inform new strategies for treatment and prevention of oral diseases. Advances in sequencing technologies have fuelled an increasing trend towards global genomic and proteomic approaches to determine the key factors that initiate oral diseases. Whilst metabolic profiling seeks to identify phenotypic changes of whole microbial communities, transcriptomic studies are exploring their complex interactions with each other and the host. This review discusses the most recent in vitro and in vivo studies of interspecies interactions within polymicrobial oral biofilms.