Relevance of biofilms in the oral cavity in the formation of dental plaque, caries and gum disease
Introduction to Biofilms
Biofilms are communities of microorganisms that grow on many solid environmental surfaces, including the human body (1,2). Biofilms are highly organized and are formed by the initial adherence of free floating single cells, termed planktonic cells, to a surface, followed by recruitment of additional cells, multiplication and growth (2). Extracellular matrix secreted by microorganisms in biofilms provide structural integrity, holding microbial communities together as masses (1). Microorganisms within biofilms communicate through the mechanism of quorum sensing, by which secreted signaling molecules called autoinducers regulate group activity, at the level of gene expression (2). Microorganisms contained in biofilms are subject to various benefits including increased resistance to antimicrobial agents, phagocytosis by immune cells, and physical removal (1,2). In contrast, planktonic cells are highly susceptible to many of these factors (2).