Bacterial invasion of pulpal dentin wall in vitro.

Instrumented root canals of extracted human teeth were inoculated with known pulpal bacterial isolates. The inoculated teeth were immersed in the appropriate culture media and incubated at 37 degrees C for varying periods. Streptococci multiplied in the root canals and invaded the radicular dentinal tubules. The extent of bacterial invasion was time-dependent. This experimental model of bacterial invasion was time-dependent. This experimental model may be useful in investigating the effect of intra-canal medicaments on microorganisms lodged in the pulpal dentin wall.