With proper care, most teeth that have had endodontic (root canal) treatment can last as long as other natural teeth. Root canals done properly have a 95% success rate. In some cases, however, a tooth that has received endodontic treatment fails to heal. Occasionally, the tooth becomes painful or diseased months or even years after treatment.
Why do I need retreatment?
As occasionally happens with any dental or medical procedure, a tooth may not heal as expected after initial treatment for a variety of reasons:
Narrow or curved canals were not treated suficeintly during the initial procedure
Complicated canal anatomy went undetected in the first procedure
The patient may have resistence to infections and not have healed completely.
The placement of the crown or other restoration was delayed following the endodontic treatment.
The restoration did not prevent salivary contamination to the inside of the tooth.
In other cases, a new problem can jeopardize a tooth that was successfully treated.
New decay can expose the root canal filling material to bacteria, causing a new infection in the tooth. A loose, cracked or broken crown or filling can expose the tooth to new bacteria (leading to a new infection). A tooth sustains a fracture. Retreatment is usually performed in two visits and involves the following:
- At the retreatment appointment the dentist will administer local anesthetic to numb the area. After the tooth is numb, the dentist will reopen your tooth to gain access to the root canal filling material. In many cases, complex restorative materials (crown, post and core material) must be disassembled and removed to permit access to the root canals.
- After removing the canal filling material, the dentist can clean the canals and carefully examine the inside of your tooth searching for any additional canals or unusual anatomy that requires treatment. The CBCT radiograph is extremely helpful.
- After cleaning the canals, the dentist will fill and seal the canals and place a temporary filling in the tooth.
- You will need to return to your general dentist as soon as possible to have a new crown or other restoration placed on the tooth to protect and restore it to full function.