Root Canal Treatment


This procedure removes dental pulp when it has become dead or infected. Dental pulp is the soft core of the tooth. It contains nerves, blood vessels, and connective tissue. The pulp extends from the top of the tooth, called the crown, all the way down to the roots, in branches called canals.


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Reasons for Procedure    TOP

Dental pulp may become infected because of:

When dental pulp becomes infected or dies, a painful abscess within the jawbone will occur. Removing dead or diseased dental pulp will prevent infection from spreading to other areas of the mouth and destroying bone around the tooth. If a root canal is not done, the tooth will need to be removed.

Common signs of pulp problems include:

  • Pain when biting down on a tooth
  • Pain when the tooth is not being used
  • Sensitivity to hot or cold food or beverages
  • Tooth discoloration
  • Swollen gums around the infected tooth
  • A draining boil-like structure (called a fistula) on the gum adjacent to the tooth

Possible Complications    TOP

Complications are rare, but no procedure is completely free of risk. If you are planning to have a root canal, your dentist will review a list of possible complications, which may include:

  • Pain and swelling
  • Surgical-wound infection
  • Persistent abscess
  • Inability to save the tooth

Factors that may increase the risk of complications include:

  • Smoking
  • Immune system disorders
  • Bleeding disorders
  • Circulatory problems that can cause healing problems, such as diabetes

Be sure to discuss these risks with your dentist before the procedure.

What to Expect    TOP

Prior to the Procedure

Your dentist will:

  • Do a thorough dental exam
  • X-ray your mouth to look at the extent of damage to the tooth


Local anesthesia will be used. The dentist will numb the area in your mouth. The anesthesia will be given as an injection.

Description of the Procedure    TOP

A small hole will be made through the top of the tooth and into the pulp. Next, steel files will be inserted to extract the pulp tissue. All teeth have 1-4 individual canals. Pulp will need to be extracted from all canals in the affected tooth. Once all pulp has been removed, the walls of the root canal will be reshaped and enlarged. Medicine will be inserted to kill bacteria.

At this point, a temporary filling may be inserted. This filling will protect the tooth. The procedure may be done within one visit or at multiple appointments. This depends on the condition of the tooth. Lastly, the canal will be dried, sterilized, and filled with a rubbery material. This material will prevent recontamination.

Immediately After Procedure    TOP

The dentist will:

  • Permanently seal the area
  • Place a gold or porcelain crown over the tooth to strengthen its structure

How Long Will It Take?    TOP

A root canal may take 1-3 appointments. Each appointment may last 1-2 hours.

How Much Will It Hurt?    TOP

You will have discomfort for a few days. Your doctor may give you pain medication.

Post-procedure Care    TOP

When you return home, do the following to help ensure a smooth recovery:

  • See your dentist for a follow-up x-ray as scheduled.
  • Be sure to follow your dentist's instructions.

Call Your Doctor    TOP

After arriving home, contact your doctor if any of the following occurs:

  • Signs of infection, including fever and chills
  • Redness, swelling, increasing pain, excessive bleeding, or any discharge from the area around the tooth
  • Tooth loosens after root canal treatment
  • Headache, muscle aches, lightheadedness, or general discomfort
  • Pain that you cannot control with the medications you have been given

In case of an emergency, call for emergency medical services right away.


Mouth Healthy—American Dental Association
National Institute of Dental and Craniofacial Research


Canadian Dental Association
Canadian Dental Hygienists Association


Root canals. Mouth Healthy—American Dental Association website. Available at:
...(Click grey area to select URL)
Accessed January 13, 2015.
What is a root canal? Academy of General Dentistry website. Available at:
...(Click grey area to select URL)
Updated January 2012. Accessed January 13, 2015.
6/2/2011 DynaMed's Systematic Literature Surveillance
...(Click grey area to select URL)
Mills E, Eyawo O, et al. Smoking cessation reduces postoperative complications: a systematic review and meta-analysis. Am J Med. 2011;124(2):144-154.e8.
Last reviewed January 2015 by Michael Woods, MD
Last Updated: 8/15/2012

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