A large cavity, a cracked tooth, or trauma to a tooth can cause the nerve inside to be irreversibly damaged. Nerve damage often causes severe pain in the tooth and surrounding gums. If this nerve damage is left untreated, the nerve will eventually die. After the nerve dies, an infection will often develop inside the tooth and around the root of the tooth. This infection can lead to severe pain, pus drainage, and life-threatening swelling.
A root canal is a procedure that removes the damaged nerve and fills in the space where it used to be with a synthetic material called gutta percha. Local anesthetic is used and root canals often feel very similar to having a filling done. Most patients have almost immediate pain reduction after the completion of root canal treatment. Root canal treatment also allows you to save your real tooth instead or taking it out and replacing it with either an implant, bridge, or partial denture.