Why do root canal treatments fail?
Incomplete Cleaning and Sealing. For root canal therapy to be successful, the canals must be thoroughly cleaned and sealed. Occasionally, the initial endodontic therapy was unable to remove enough irritants inside your tooth that it fails to heal or pain continues. More often, the canals are so narrow, hardened, or curved that the tiny instruments used to clean and shape them cannot completely pass through. Other canals are so small they are extremely difficult to find and went undetected or missed during the first procedure. New Decay, Broken Restoration, or Leaking restoration. These can expose the root canal filling material to bacteria and other irritants in the saliva, causing a new infection in your tooth and an abscess at the end of the root. Fracture. Trauma may have caused the root to fracture.
