Dental Plaque and Biofilm Formation

Plaque and Biofilm

• Plaque: An older term encompassing biofilm and firepile.
• Plaque can attach to:
  • Tooth surfaces.
  • Tissue.
  • In between, not attached to any surface.

Biofilm Formation Stages

1. Acquired Pellicle
2. Colonization
3. Maturation
4. Mineralization: Can occur within 4-8 hours.

Mineralization

• Toothpastes claim 12-hour protection with twice-daily brushing, but mineralization can occur much faster (4-8 hours).
• Factors influencing mineralization speed:
  • Mouth dryness/moisture
  • Diet
  • Sugar intake (plaque thrives on sugar)
• Healthy diet (e.g., apples) and natural cleaning may slow down mineralization to the 8-hour mark.
• Soft diets and sugary drinks accelerate mineralization towards the 4-hour mark.
• Biofilm accumulation over 10-12 days leads to inflammation.

Subgingival Biofilm

• Decafloss disappearing into the "poobilla" indicates subgingival biofilm.
• Toothbrush bristles reach 2-3 mm below the gumline on the facial and lingual surfaces.
• Brushing and flossing every 12 hours helps control biofilm and bacteria.

Aging Biofilm

• Becomes more anaerobic.
• More motile (moving around).
• Shifts to gram-negative bacteria.
• Changes to rods, spirochetes, and vibrios, which are more mobile.
• Increases in number and virulence (becomes more harmful).

Healthy vs. Unhealthy

• Healthy biofilm is relatively simple and sparse.
• Unhealthy biofilm:

Healthy Bacteria

• Most bacteria are gram-positive (e.g., streptococcus, actinomyces).
• Streptococcus: cocci (spherical)
• Actinomyces: rods (elongated)
• They adhere to the pellicle.

Biofilm Development

• Within hours, cells form layers, colonies, and masses.

Coaggregation

• Aggregation: Coming together.
• Coaggregation: All coming together at the same time.