04/08/2026
1. Root Canal Teeth Become Immunologically Isolated
After endodontic therapy:
• pulp and blood supply are removed
• no immune surveillance exists
• antibiotics pe*****te poorly
Without circulation, immune cells cannot reach bacteria living in dentinal tubules or at the root apex.
This creates a low-oxygen ecological niche, which is ideal for anaerobes.
2. Dentinal Tubules Provide Deep Microbial Shelter
Dentin contains thousands of microscopic tubules that extend from the pulp to the outer tooth surface.
Approximate numbers:
• 20,000–45,000 tubules per square mm
• diameter up to 3 µm
Bacteria can pe*****te hundreds of microns into these tubules.
Once inside:
• Irrigants cannot reach them
• mechanical instrumentation cannot remove them
• immune cells cannot enter
This allows anerobic organisms even after seemingly adequate root canal