Endodontic Re-Treatment


Endodontic retreatment - nsbendo

North Shore & Brookline Endodontics provides endodontic therapy, including re-treatments, in Brookline, Lynn, Peabody, Beverly, Gloucester, and Newburyport. Contact us today at one of our six locations to learn more about our services and schedule your appointment. 

Root canal treatment enjoys a 90-95 percent success rate. Occasionally, infection returns and the root canal fails. In these circumstances, you may need a procedure called endodontic re-treatment. 

Endodontic re-treatment involves reopening your tooth to clean, sanitize, and reshape the chamber and canals in order to save your tooth. At North Shore & Brookline Endodontic, we take the time to thoroughly assess the risk factors in every case.  When needed, we use 3D imaging (CBCT scans) to evaluate and determine the best treatment option for your specific needs.  

Endodontic re-treatment is best performed by endodontists. Endodontists receive two or more additional years of training after dental school in order to specialize in the treatment of tooth pain and root canals. No one is more qualified to perform these procedures than an endodontist, so you can feel confident knowing you’re getting the best possible care.


When Endodontic Re-Treatment Is Needed


It is unusual for root canals not to heal properly, but complications can occur under the following circumstances:

  • Calcified or narrow canals that were not initially treated
  • Complicated root anatomy
  • Delayed placement of a final restoration
  • Bacterial leakage due to inadequate final restoration
  • New decay
  • A loose, cracked, or broken crown exposing the tooth to bacteria
  • Fracture

In other cases, the initial root canal does heal properly, but reinfection occurs months or years down the line after a new injury or damage to the tooth.


Alternatives to Endodontic Re-Treatment


In some cases a surgical procedure called apicoectomy can be performed instead of re-treatments.  If neither re-treatment or apicoectomy is possible, your tooth can be extracted and replaced by a bridge or dental implant.  Our goal as endodontists is to preserve your teeth.


Root Canal Retreatment (Explained)



Root Canal Retreatment (Summarized)



Frequently Asked Questions About Endodontic Re-Treatment


Do root canals need to be redone?


In most cases, a root canal treatment will last a lifetime. Occasionally, a tooth will become reinfected, in which case a second root canal, or endodontic re-treatment, is needed.


Can a root canal fail 20 years later?


Yes, root canals can fail months after treatment or years after treatment. There are many potential causes for this—your crown may be loose, new decay may have formed under the crown, or the tooth could have fractured.


Is root canal re-treatment successful?


Root canal re-treatment can have up to an 90 percent success rate, depending on the circumstances. Choosing a skilled endodontist increases the odds of a successful outcome.


Should I re-treat a root canal?


If your tooth is re-infected, your choices are to have it extracted or have endodontic re-treatment. Saving your natural tooth is always preferable to extracting a tooth and having to replace it with a bridge or dental implant, so re-treatment is recommended. If your original root canal was performed years ago or by another provider, we may be able to offer new techniques for better results.


How do you do endodontic re-treatment?


Endodontic re-treatment is similar to your original root canal, with a few differences.  Getting access to root canal space may require removal of a crown, posts and other restorative materials first. Then the original root canal filling is removed, and the root canal space is re-cleaned and sealed.


What are the symptoms of a failed root canal?


The most common sign of a failed root canal is pain—this could be only when you eat or bite or a persistent pain that doesn’t go away. You’re also likely to experience swelling and tenderness. You may have a fistula, which is a pimple-like bump near the affected tooth, or notice that your tooth feels loose.


What can I expect after root canal re-treatment?


You can expect a recovery that is similar to your first root canal—you may have some mild pain, tenderness, and swelling near the tooth. Cold compresses and over-the-counter pain relievers can alleviate such discomfort. Eat soft foods and avoid chewing with the affected tooth until any pain subsides.


Do I need a new crown after root canal re-treatment?


No, the crown is almost never removed for root canal re-treatment. In many cases, your endodontist can go through the crown and complete treatment.  Your dentist will advise you if a new crown is needed or the old one can be repaired.