Which term describes the protective matrix that houses bacteria in dental plaque?

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

Answer: (B)

Biofilm is the term for the protective matrix that houses bacteria in dental plaque. Bacteria produce extracellular polymeric substances that form a cohesive, hydrated matrix, embedding the cells and attaching the community to the tooth surface. This matrix guards the bacteria from mechanical disruption and helps resist antimicrobials and host defenses, while also enabling nutrient sharing and communication within the group. Plaque is the overall deposit of bacteria and matrix on the tooth, and calculus is mineralized plaque. The pellicle is the saliva-derived film that coats enamel and provides the initial surface for bacterial adhesion but isn’t the bacterial matrix itself.