A biofilm is an assemblage of surface-associated microbial cells that is enclosed in an extracellular polymeric substance matrix.

Van Leeuwenhoek, using his simple microscopes, first observed microorganisms on tooth surfaces and can be credited with the discovery of microbial biofilms.

Features of Biofilms:-

• Biofilms can form on medical implants within human tissues. Ex. Biofilm formation on oral implants can cause inflammation of peri-implant tissues, which endangers the long-term success of osseointegrated implants.
• Biofilms are formed on all types of surfaces existing in food plants ranging from plastic, glass, metal, cement, to wood and food products.
• Microbial cells within biofilms have shown 10–1000 times more antibiotics resistance than the planktonic cells