Few treatments have a worse reputation than the root canal, and few deserve it less. Most of the pain people associate with a root canal is the pain of the infection before treatment, not the treatment itself.
Inside every tooth is soft tissue called the pulp. When deep decay, a crack or an injury lets bacteria reach it, the pulp becomes inflamed or infected. That causes the throbbing, night-time pain many patients describe.
During treatment the tooth is numbed completely. The dentist makes a small opening, removes the infected pulp, cleans and shapes the canals, disinfects them and seals them. Most patients say it feels like a long filling.
Afterwards the tooth can be tender for two or three days. Because a treated tooth becomes more brittle, a crown is usually placed to protect it. With a crown, a root-canal-treated tooth can last for many years.
Signs you may need one: lasting sensitivity to hot, pain when biting, a gum pimple near a tooth, or a tooth that has darkened. Early treatment is simpler, so do not wait for the pain to become severe.