Root Canals
For teeth to remain alive and healthy, each tooth is supplied by nerves and nutrients through a chamber called the root canal. As decay spreads downward and into a decayed tooth, the decay encroaches on the pulp chamber of that tooth, which contains the nerve. This is often what leads to a toothache. To remove all of the decay from the tooth, sometimes it is necessary to remove the nerve of the tooth entirely and replace the empty canal with a root canal filling.
Retreatments
Unfortunately, root canals are not always entirely effective in removing all bacterial contents from the tooth’s chamber. Even if only a little bit of bacteria persist in the tooth’s root, it can sometimes lead to recurrent infection and pain. A root canal specialist (endodontist) is skilled in re-treating the canal chamber by removing the previous root canal filling and intensely cleaning it before filling it again and hoping for improved results.