Written by Calvin Bennet · Medically reviewed by Dr. Scott A. Puckett, DDS · Updated September 2026
A root canal treats a tooth whose inner pulp has become infected or inflamed. The dentist or endodontist numbs the tooth, removes the pulp, cleans and shapes the canals, and seals them — saving the natural tooth. Despite its reputation, most people say it feels about like getting a filling.
What is a root canal?
A root canal removes infected or inflamed pulp from inside a tooth, then cleans, disinfects, shapes, fills, and seals the canals so the natural tooth can be saved rather than pulled.
When you need one
Deep decay, a crack, or an injury can let bacteria reach the pulp — often signaled by lingering pain, sensitivity to hot or cold, or swelling. If the pulp is infected, a root canal (or extraction) is usually needed.
What to expect during treatment
The tooth is numbed with local anesthesia and isolated with a thin rubber sheet (a “dam”). The dentist makes an opening, removes the pulp, cleans and shapes the canals, then fills and seals them. Most root canals are completed in one visit of about 30–90 minutes. You may feel pressure, but not sharp pain.
After the procedure
Mild soreness for a few days is normal. The treated tooth usually needs a crown afterward to protect it from breaking, so plan on a follow-up visit.
Does a root canal hurt?
A root canal relieves pain rather than causing it — the tooth is fully numbed, and most patients compare it to getting a routine filling.
Sources
Frequently Asked Questions
Is a root canal painful?
No — the tooth is numbed with local anesthesia, and the procedure actually relieves the pain of an infected tooth.
How long does a root canal take?
Usually one visit of about 30 to 90 minutes, depending on the tooth.
Do I need a crown after a root canal?
Often yes — a crown protects the treated tooth from cracking, especially on back teeth.
How long does a root-canal tooth last?
Many years with a proper restoration; see our guide on how long a root-canal tooth lasts.
Related reading
Medical disclaimer: this article is for general education and is not a substitute for professional dental advice, diagnosis, or treatment. Talk to your dentist about your specific situation.