from Purnima S Kumar, Matthew R Mason and Janel Yu writing in Oral Microbial Ecology: Current Research and New Perspectives:
Dental plaque biofilm is composed of a diverse microbial community. Several decades of research have been focused on the role played by the subgingival biofilm in the etiology of periodontal diseases. However, recent evidence from other ecosystems within the human body indicates that these biofilms also play an important role in maintaining health. The purpose of this review is to explore the health benefits of subgingival plaque, and to outline the development of the biofilm as well as to characterize the bacteria present in the plaque biofilm in health and disease. Additionally, the virulence mechanisms of health and disease-associated biofilms will be outlined.
Further reading: Oral Microbial Ecology: Current Research and New Perspectives