Can a Root Canal Fail?
A common question our patients ask is, “Can a root canal fail?” While the answer is yes, you need to understand more about root canals, why they fail, and how to reduce your risk of root canal failure. We’ll break the myths and help you understand the facts behind root canal therapy so you feel more comfortable when you get your procedure.
What Is a Root Canal Failure?
Root canal failure is very rare. The success rate of this procedure ranges from 82.0% based on a strict definition to 92.6% using a loose definition of failure. Per the study, the loose and strict definitions for success came from X-ray images taken after the root canal. The strict definition requires no signs of inflammation to be a success. The looser definition allows an area of inflammation to show signs of shrinkage after a root canal to indicate a successful treatment.
Failure of a root canal means some infectious material remains in the tooth after the procedure, or the tooth becomes newly infected after the treatment. This bacteria can trigger new inflammation and infection in the tooth, causing pain when you should start to feel better.
Why Do Root Canals Fail?
Despite the high success rate of root canals, failures can occur for several reasons, some of which fall outside the skills of the endodontist.
Occasionally, teeth can have highly intricate passages that the doctor cannot access or find during a standard root canal. If any bacteria remains, even in inaccessible places inside the tooth, the root canal can fail.
Other causes of root canal failure can happen after the procedure and include:
- New decay in a treated tooth
- Filling falling out
- Crown falling out or not fitting correctly
- A crack in the treated tooth
If you have a treated tooth, you may not realize that the root canal failed initially. However, over time, you’ll develop some signs of a developing problem.
Common Signs of a Failed Root Canal
Over time, a tooth with a failed root canal will show symptoms that something is wrong. If the treatment itself fails, you may notice new pain or pain that doesn’t start to lessen after two or three days. Talk to your endodontist about any concerning symptoms you have during recovery from your initial root canal.
A root canal can also experience failure long after the treatment. Decay or new damage to the tooth can allow bacteria to get inside, requiring retreatment. Watch out for the following symptoms to indicate a root canal failure in a treated tooth:
- Swelling or redness on the gums at the base of the tooth
- Sensitivity to temperatures
- Pain when biting down or chewing
- Persistent tenderness
- Loosening of the tooth
Whenever you notice any of the above signs, you should call an endodontist for an exam and possible retreatment of the tooth.
Endodontic Retreatment for Root Canal Failures
If a root canal fails, you need endodontic retreatment to preserve the tooth. Find out more about this process below.
Who to See for Endodontic Retreatment
While some dentists perform root canals, they will not do endodontic retreatment. No matter where you went for your root canal, you need to see an endodontist for retreatment. Endodontists have the training and tools needed to see whether retreatment or surgery is a better option. They also have the necessary knowledge and skills needed to retreat a formerly endodontically treated tooth or perform apicoectomy surgery as needed.
Endodontic Retreatment Process
Endodontic retreatment is non-surgical and uses a local anesthetic. Therefore, you can drive yourself back home to work or school after your appointment.
The process of this retreatment includes the following steps, which the endodontist adapts to your dental needs:
- Prepare your mouth for the procedure by placing a dental dam to isolate the tooth and numbing the treated area.
- Remove the dental work on the tooth, including the filling from the original root canal.
- Examine the canals inside the tooth to find areas the first treatment missed.
- Clean and sanitize the inside of the tooth to remove any infection from the tooth.
- Reseal and fill the tooth.
You may need to get a new crown on the tooth if you need one after the first root canal. Your dentist can fit you with a new crown if you need one. Make sure to keep all follow-up appointments your endodontist or dentist requests after your retreatment.
Root canals rarely fail, but if you do need retreatment in a tooth, rest assured that the process will likely save the tooth. Endodontic retreatment has a high success rate of 90.4% after two years, according to a study supported by the American Association of Endodontists Foundation.
How to Raise the Chances of Root Canal or Retreatment Success
There are some things that you can do to increase the chances of success after either root canal therapy or endodontic retreatment.
Follow Your Doctor’s Instructions
First, follow your endodontist’s requirements about follow-up care and getting a crown or other dental work to protect the tooth. Waiting too long raises the chances of the tooth sustaining damage before it gets a reinforcing crown.
Take Care of All Your Teeth
Second, practice excellent oral hygiene for all your teeth, including your treated tooth. Brush and floss twice daily and see your dentist two times a year. Regular dental care to prevent cavities also helps protect endodontically treated teeth from new decay.
Protect the Treated Tooth
Finally, use caution when using the tooth to avoid damaging the crown or filling over it. Don’t bite down with that tooth on hard foods, and wear a mouthguard to keep all your teeth protected when playing contact sports. These habits will reduce the chances of cracking a treated tooth.
While you cannot stop all causes of needing retreatment, you can do the above to raise the chances that your root canal or retreatment will last for life.
Don’t Let a Failed Root Canal Cost Your Tooth
If you notice any symptoms of a failed root canal, even years later, you should consider endodontic retreatment to prevent tooth loss. Contact us at your closest Southwest Endodontics (Geneva or Orland Park) for an examination to determine if retreatment is necessary. We offer painless and compassionate endodontic care every day to save your teeth.