All surgeries have a risk of complications, and root canal treatment is no different. There are many different reasons why your root canal may need retreatment or an additional surgery. Although it is not common for root canals to fail, here is why they sometimes do and why retreatment is your best option.
Endodontists do their best to remove all of the infection-causing bacteria in the tooth, but occasionally some of the bacteria can remain. Any left-behind bacteria can re-infect the tooth and cause more inflammation in the pulp.
Bacteria may also re-infect the tooth if a permanent filling is not placed soon after the root canal treatment. A temporary filling can breakdown or leak and allow bacteria into the canal.
If your tooth has more than the typical numbers of canals, then it is possible that one could be missed during the process. The unfilled canal will still be infected and the bacteria will multiply, infecting the other canals and leading to retreatment.
These mistakes occur very rarely as root canals have a 95% success rate. But, when they do, retreatment is needed to prevent further damage. It is best to visit an endodontist for retreatment. Retreatment can be very difficult and having a specialist doing the procedure is vital to success.