What term describes the combination of bacteria and other particles that adhere to the outside of a tooth?

• A. Plaque
• B. Calculus
• C. Tartar
• D. Biofilm

Answer: (A)

Dental plaque is the soft, sticky film that forms on teeth when bacteria in the mouth mix with saliva and food particles. This film adheres to the tooth surface, especially along the gumline, and can begin forming within hours after brushing. It’s a community of bacteria embedded in a sugary, protein-rich matrix, which makes it a biofilm that firmly sticks to enamel. If plaque remains, the acids produced by the bacteria can erode tooth enamel and contribute to decay and gum disease. When plaque calcifies over time, it becomes calculus (tartar), a hard deposit that is much harder to remove and typically requires professional cleaning. Biofilm is the broader idea of a bacterial community on a surface, but the specific term for the combination described here is plaque.