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What you need to know about root canals

Root canal treatment has given dentists a safe way of saving teeth. Sometimes the tooth’s soft core (the dental pulp) inside your tooth becomes inflamed or infected. This can be caused by deep decay, repeated dental procedures on the tooth, a crack or chip in the tooth or a blow to the tooth.

Years ago, teeth with diseased or injured pulps were removed. Today, your dentist uses root canal treatment to remove the infected dental pulp and preserve your tooth.

What are the signs I may need root canal treatment?

Signs to look for include pain, prolonged sensitivity to heat or cold, discoloration of the tooth, and swelling and tenderness in the nearby gums. But sometimes, there are no symptoms.

Dentists use a variety of methods to determine which teeth need root canal treatment. One of the first evaluations is a percussion test, where your dentist will tap on the top and possibly the sides of your teeth to assess any pain or tenderness. Other evaluations include hot/cold testing, electric pulp testing, anesthesia or a cavity test.

How does dental pulp get infected?

Dental pulp is the soft tissue that contains nerves, blood vessels and connective tissue. It lies within the tooth and extends from the crown of the tooth to the tip of the root in the bone of the jaws.

When the pulp is diseased or injured and can't repair itself, it dies. The most common cause of pulp death is a cracked tooth or a deep cavity. Both of these problems can let bacteria enter the pulp and cause an infection inside the tooth. Left without treatment, pus builds up at the root tip, in the jawbone, forming a pus pocket called an abscess. Left untreated, an abscess can spread to the bone around the teeth and cause permanent damage. Untreated pulp can also develop a severe infection, which may eventually cause sepsis.

Why does the pulp need to be removed?

When the infected pulp is not removed, pain and swelling can result, and the infection can damage your bone. Without treatment, your tooth may have to be removed.

What does root canal treatment involve?

Procedures generally go like this:

1. Your tooth and the surrounding area are numbed with anesthesia.

2. The dentist drills a hole to access the source of decay.

3. Using a long cleaning file, the dentist removes the pulp, bacteria and decayed nerve tissue. He or she scrubs the sides of the canal, using water or sodium hypochlorite to wash away the debris.

4. Almost done! The tooth is sealed, using a temporary or permanent filling. The dentist may choose a temporary filling if he or she wants to apply medication inside the tooth or check the tooth’s recovery after several days. When the tooth is ready for a permanent filling, the dentist places a mixture called gutta-percha in the root canal and fills the access hole with resin or amalgam.

5. Finally, you might need follow-up appointments to place a crown or other restoration. Such restoration can protect a tooth weakened by decay and treatment.

Will the tooth need any special care or additional treatment?

You should not chew or bite on the treated tooth until you have had it restored by your general dentist because your tooth could fracture. Otherwise, just practice good oral hygiene: brushing, flossing and regular checkups and cleanings. Endodontically treated teeth can last for many years, even a lifetime.

How long does the restored tooth last?

Your restored tooth could last a lifetime if you continue to care for your teeth and gums. However, regular checkups are necessary and you may need a crown on your treated teeth, since they’re weaker than live teeth. As long as the roots of a treated tooth are nourished by the tissues around it, your tooth will remain healthy.

Who performs a root canal?

All dentists, including your general dentist, received some training in endodontics while in dental school. Endodontists are specialists who perform only endodontic procedures, both routine and complex. They are also experienced at finding the cause of oral and facial pain that is difficult to diagnose. Your primary care dentist may refer you to an endodontist for root canal treatment.

Learn about root canal treatment

  Common procedures: root canals

Last updated February 10, 2022

The oral health information on this website is intended for educational purposes only. Always consult a licensed dentist or other qualified health care professional for any questions concerning your oral health.