What Is a Root Canal?

A root canal is a treatment used to repair and save a tooth that is badly decayed or infected. A tooth's nerve and pulp can become irritated, inflamed, and infected due to deep decay; repeated dental procedures on a tooth; or large fillings, a crack, or chip in the tooth. It also can happen because of trauma to the face.

During a root canal procedure, the nerve and pulp of the tooth are removed and the inside is cleaned and sealed. Without treatment, the tissue surrounding the tooth will become infected and an abscess may form.

A tooth's nerve is not vitally important to a tooth's health and function after the tooth has come through the gums. Its only function is sensory -- to give the sensation of hot or cold. The absence of a nerve won’t affect how your tooth works.

Root canal procedures have the reputation of being painful. But the procedure itself is no more painful than having a filling placed.

Why Does Tooth Pulp Need to Be Removed?

When a tooth's nerve tissue or pulp is damaged, it breaks down and bacteria begin to multiply within the pulp chamber. The bacteria and other decayed debris can cause an infection or abscessed tooth. An abscess is a pus-filled pocket that forms at the end of the roots of the tooth. An abscess happens when the infection spreads all the way past the ends of the roots of the tooth. An infection in the root canal of a tooth can also cause:

• Swelling that may spread to other areas of the face, neck, or head
• Bone loss around the tip of the root
• Drainage problems extending outward from the root. A hole can occur through the side of the tooth with drainage into the gums or through the cheek with drainage into the skin.

What Are the Signs That a Root Canal Is Needed?

If you need a root canal, you may notice these signs:

• Tooth sensitivity that lingers, especially to heat or cold
• Sharp pain when chewing or biting which sometimes poorly responds to pain relievers 
• Pimples on your gums
• Chipped or cracked teeth
• Swollen or painful gums
• Deep decay or darkened gums

Root Canal Procedure

The procedure will follow these steps:

• Your dentist will take an X-ray to see the shape of the root canals and determine if there are any signs of infection in a surrounding bone. They’ll use local anesthesia to numb the area near the tooth. You may not need anesthesia since the nerve is dead, but most dentists still anesthetize the area to make you feel more relaxed.
• To keep the area dry and free of saliva during treatment, your dentist will place a rubber dam (a sheet of rubber) around the tooth.
• The next step is drilling an access into the tooth. The pulp, bacteria, and decayed nerve tissue are removed from the tooth. The area is cleaned out using a series of root canal files. They’re placed into the access hole and work down the full length of the tooth to scrape and scrub the sides of the root canals. As the work is done, water or sodium hypochlorite will be sprayed in the area to flush away the debris.
• Once the tooth is thoroughly cleaned, it’s sealed. Some dentists like to wait a week before sealing the tooth. For instance, if there is an infection, your dentist may put a medication inside the tooth to clear it up. Others may choose to seal the tooth the same day it is cleaned out. If the root canal isn’t completed on the same day, a temporary filling is placed in the exterior hole in the tooth to keep out saliva and food between appointments.
• At the next appointment, to fill the interior of the tooth, a sealer paste and a rubber compound called gutta percha are placed into the root canal. A filling will be put in to close the access hole created at the beginning of treatment.
• The final step may involve further restoration of the tooth. A tooth that needs a root canal often is one that has a large filling or extensive decay or other weakness. Because of that, you may need a crown, crown and post, or other restoration to protect it, prevent it from breaking, and restore it to full function. Your dentist will discuss the need for any additional dental work with you.

Root Canal Recovery

After a root canal, your mouth will be numb for a couple of hours. Most people can go right back to work, school, or other activities. You may want to wait until the numbness is gone before eating.

For the first few days following the completion of a root canal, the tooth may feel sensitive due to tissue inflammation, especially if there was pain or infection before the procedure. This usually can be eased with over-the-counter pain medications such as ibuprofen (Advil, Motrin) or naproxen (Aleve).

Until your root canal procedure is completely finished, with a permanent filling in place or crown, try to avoid chewing with the tooth. This helps keep the area clean and may prevent a fragile tooth from breaking before it can be fully restored.

Brush, floss, and use an antiseptic mouthwash as you regularly would and see your dentist at normally scheduled intervals.

Root Canal Outlook  

A root canal treatment is highly successful; the procedure has more than a 95% success rate. Many teeth fixed with a root canal can last a lifetime.

Root Canal Complications

New infections might happen after a root canal. Among the likely reasons for this include:

• More than the normally anticipated number of root canals in a tooth (leaving one of them uncleaned)
• An undetected crack in the root of a tooth
• A problem with the restoration that has allowed bacteria to get past it into the inner tooth
• A breakdown of the inner sealing material over time, allowing bacteria to recontaminate the inner tooth

Sometimes retreatment can fix the problem, but other times you may need surgery to save the tooth. The most common procedure is an apicoectomy, or root-end resection. It relieves the inflammation or infection in the bony area around the end of your tooth. In this procedure, the gum tissue is opened, the infected tissue is removed, and sometimes the very end of the root is removed. A small filling may be placed to seal the root canal.

Root Canal Cost

The cost varies depending on how severe the problem is and the tooth affected. Many dental insurance policies at least fully or partially cover this treatment. 

Root Canal Alternatives

Saving your natural teeth is the very best option, if possible. Your natural teeth allow you to eat a wide variety of foods necessary to maintain proper nutrition. The root canal procedure can help save your teeth.

The only alternative to a root canal procedure is having the tooth extracted and replaced with a bridge, implant, or removable partial denture. These alternatives are more expensive than a root canal procedure and need more treatment time.

Root Canal Prevention

Since some of the reasons the nerve of a tooth and its pulp become inflamed and infected are due to deep decay, repeated dental procedures or large fillings, there are steps you can take to help you avoid a root canal:

• Brush at least twice a day.
• Floss at least once a day.
• Wear a mouth guard to avoid sports-related injury.
• See a dentist at least once every 6 months for a dental checkup