In some rare cases, root canal therapy may not achieve the desired outcome. The treated tooth may not heal properly or post-surgical complications can arise, putting the tooth at risk. Root canal retreatment involves the removal of the previous crown and packing material, cleansing of the root canals, and re-packing and re-crowning the tooth. Essentially, it is similar to the initial procedure, excluding the structural removal. The success rate for root canal retreatment is approximately 75%.

For most people, root canal treatments and retreatments are preferable to tooth extraction. If a tooth has good bone support, a solid surface, and healthy gums, there is a good chance of saving it. Opting for root canal retreatment is often more cost-effective compared to alternatives such as dental implants or extensive bridgework. These alternatives are more expensive, require ongoing maintenance, and may not feel as natural as a natural tooth.

Why is root canal retreatment required?

Root canal retreatment, although it may not sound appealing, is a relatively straightforward procedure. Typically, it can be completed within 1-3 visits.

Several factors can contribute to the unexpected failure of root canal therapy, including:

1. Leaking filling material due to a cracked crown.
2. Curved or narrow canals that were not adequately treated during the initial procedure.
3. Delay in placing restorative devices after the treatment.
4. New decay affecting the tooth.
5. New fracture occurring in the previously treated tooth.
6. Saliva entering the restored structure.
7. Undetected complex canal structures..

What does root canal retreatment involve?

During a root canal retreatment procedure, a local anesthetic is typically administered, unless an alternative option is chosen. To protect the tooth from bacteria and saliva, a rubber dam is placed around the affected tooth. The extent of the treatment performed in a single appointment depends on the level of inflammation and the complexity involved.

The initial step of the retreatment involves gaining access to the inner part of the tooth. If a crown and post were previously placed, they will be removed.

Next, the filling material and any obstructions blocking the root canals are removed using an ultrasonic handpiece, which helps vibrate and dislodge unwanted materials. Small instruments are then used to thoroughly clean and reshape the root canals, with X-rays taken if necessary to ensure proper cleaning. If the complexity requires it, medicated packing material may be applied, and the remaining cleansing procedure will be completed during the next visit.

Once the dentist is satisfied that the root canals are thoroughly cleaned, they will be packed with gutta-percha, a rubbery material that seals the canals to prevent bacterial invasion. Finally, a temporary crown or filling is placed on the tooth. In a subsequent appointment, a permanent crown that matches the tooth's color will be placed.

If you have any questions or concerns about root canal retreatment, please ask your dentist.