The symptoms of a failed root canal treatment (RCT) includes:
- pain returning to the tooth after RCT has been completed for a period of time
- swelling of the face or inside the mouth
- discharge around the treated tooth
In your case, if you are experiencing pain after 4 years, it is possible that infection has returned to the tooth. You are recommended to visit your dentist/endodontist so that he/she can do a thorough examination of your tooth.
If the tooth can be salvaged, a second RCT can be done. If the infection is too serious and the tooth cannot be saved, then extraction and tooth restoration (eg. dental implant) can be done.
Best regards,
Dr Irene Sim