Bakterien in den Dentinkanälen von wurzelgefüllten Zähnen

An example from scientific literature:
Bacterial Invasion into Dentinal Tubules of Human Vital and Nonvital Teeth; Journal of Endodontics, Vol. 21, No. 2, pp.70-73, 1995
1Shigetaka Nagaoka, DDS,PhD, 1Youichi Miyazaki, DDS, Hong-Jih Liu, DDS, PhD, 1Yuko Iwamoto, DDS,
2Motoo Kitano, DDS, PhD, and 1Masataka Kawagoe, DDS, PhD
1Department of Operative Dentistry and Endodontology and
2Department of Oral Pathology,
Kagoshima University Dental School, Kagoshima, Japan

Summary: Whereas in vital teeth – after 150 days of the fillings left open – only 1.1 % of the
dentinal tubules were infected by bacteria, 39.0% of the tubules of root-filled nonvital teeth were infected by bacteria.

The conclusions from this are:
  1. In the dentinal tubules the odontoblasts create a physiological barrier against a bacterial invasion of the vital tooth.
  2. In the dead tooth, however, this role of the odontoblasts as a physiological barrier against a bacterial invasion disappears, as the odontoblasts degenerate, allowing the bacteria to easily penetrate the tubules.