What is dental biofilm?

• A. Microbial communities in the mouth; cell-to-cell contact is mediated by specific protein adhesins and often polysaccharide receptors
• B. A mineral deposit on enamel
• C. A sterile film on teeth
• D. A single species of bacteria in the mouth

Answer: (A)

Dental biofilm is a living, multispecies microbial community that attaches to the tooth surface and grows within a self-produced extracellular matrix. It starts when bacteria bind to the acquired enamel pellicle using specific protein adhesins that recognize receptors on the surface, and then they connect to each other through cell-to-cell interactions. As the community develops, microbes secrete polysaccharides and other matrix components that form a sticky, hydrated scaffold, keeping cells together and protecting them. This structured, cooperative ecosystem explains why dental biofilm is not just a mineral deposit or a sterile film, nor a single species, but a dynamic, layered community capable of persistent colonization and metabolic activity in the mouth.