Most of the current studies in the dental literature report that root canal therapy has a 95-97% chance of success, if performed by a specialist (Endodontist). Occasionally, root canal therapy fails to completely heal a diseased tooth, due to factors such as recontamination. Often when this happens, another root canal treatment procedure (Endodontic Retreatment) is recommended in order to save the tooth. Endodontic retreatment is similar in technique to root canal therapy, but more challenging and time consuming.
Reasons for Retreatment
Contamination: When the root canal filling is exposed to bacteria as a result of decay or leakage of saliva, the treatment area may become infected again, and retreatment is recommended.
Root canals are not thoroughly cleaned and sealed: For treatment to be effective, the root canals must be thoroughly cleaned and sealed as close to the tip of the root as possible. Failure to achieve this can increase the likelihood of the root canal spaces becoming infected and requiring retreatment.