With modern technology and the right expertise, root canals are as convenient and comfortable as a common filling. Although endodontic treatments are completely successful the majority of the times, patients should be aware of potential complications. As such, it is important for you to understand why an infection can occur after a root canal. You should also know what symptoms indicate you should contact your dental care provider for a follow-up.

Infections After a Root Canal

Although it is rare, it is possible for an infection to develop after a root canal. They can appear as soon as about one week after the root canal, but it is possible for issues to arise even a decade later. They develop for a number of reasons:

  • An undetected crack in the tooth’s root has gone unresolved.
  • The tooth houses an abnormal number of canals and at least one went untreated.
  • The restoration which covers the root canal was ineffective, which allowed bacteria to reenter and reignite an infection.
  • The sealing meant to keep the restoration together degraded over time, which has allowed bacteria to recontaminate the inside of the tooth.

Symptoms of Root Canal Complications

Many of the potential signs of a failed or failing root canal overlap considerably with the same symptoms that revealed the need for a root canal in the first place. These can include tenderness, sensitivity to touch, swelling, persistent boils, bad taste/odor from the area, and general pain. The symptoms can be constant or intermittent. The severity of symptom may also waver. In fact, not every problem tooth will display detectable symptoms. It is not uncommon for a patient to feel as though the tooth is totally fine, only to have an x-ray exam reveal a problem. This is why preventive medicine, including regular dental visits, is so important for long-term oral health.

On the flip side, experiencing these common symptoms in no way guarantees endodontic failure. It is possible that they are in not related to the root canal procedure at all. For example, some patients experience “referred pain.” This is when an issue elsewhere along the length of a nerve in your mouth happens to create an uncomfortable sensation that feels like it is from your root canalled tooth, even though it is not. Another potential culprit is “phantom pain,” which is similar to the phantom limb pain amputees sometimes report.

Treating Root Canal Infections

In most instances, if the root canal has been fully successful, it will be totally asymptomatic. So, if your tooth canal experiences any of these symptoms after the typical period of healing has passed, you would likely benefit from a professional evaluation by your dentist or endodontist. As a general rule, patients should schedule their appointments sooner rather than later. Endodontic issues can be unpredictable, so there is the potential that flare-up could occur, shifting your situation from one of minor discomfort into acute, severe pain and/or swelling at any moment. However unlikely such a problem might be, there is simply no reason to delay seeking attention.

About the Author

Dr. Harris has been a practicing dentist since 2005. In 2012, he received his Master’s of Science in Dentistry and a certificate in Endodontics. He founded East Coast Endodontics shortly after receiving his master’s degree. He also currently holds a part-time position as a Clinical Assistant Professor for the Endodontics department at Virginia Commonwealth University. View his full bio.