Root Canal Therapy Rarely Fails… But Here’s Why It Might

Root canal therapy in Flagstaff removes infected pulp from the interior of infected teeth, then cleans and seals that tooth to prevent reinfection. Root canal therapy near you is almost routinely effective with a success rate of over 95%. Even a procedure with a success rate that high, though, can occasionally fail. A failed root canal therapy is when the infection is not entirely removed from the treated tooth, but later spreads to other teeth. Another type of failure that can arise is if the crown that was placed onto the treated tooth loosens or breaks, letting bacteria into the previously treated tooth to create a new round of infection.

Why do root canals sometimes fail?

There are three common causes of root canal therapy. Having said that, the failure of root canal therapy is completely uncommon. When it does occur, though, it can often be traced to one of these three causes:

Coronal leakage. The placement of a crown over a tooth treated with root canal therapy is an essential step to completing your root canal. It is not a final step to be neglected or delayed. That crown is essential to prevent bacteria from re-entering the tooth which, while sealed with gutta percha at the end of the procedure, is not impervious to reinfection. Even after that crown is placed, it is essential to maintain its integrity. One of the most likely causes of a failed root canal is bacteria leaking into a loose or damaged crown.

Unique characteristics of the infected tooth. Not all teeth are identical. While there is a typical interior structure to teeth, generally, many teeth have more roots or canals that a dentist may expect. Some roots may be entirely unknown to the dentist because it was not revealed by the pre-surgery dental x-rays. If there was, unbeknownst to the dentist, that unseen root is infected, the progress of that infection may ultimately require further root canal treatment.

Root perforation. Root perforation occurs when a dentist in Flagstaff accidentally damages or punctures the root of a tooth being treated during the course of treatment. Those perforations can be repaired but, if they go undetected at the time, they can allow bacteria to re-enter the tooth from elsewhere within the jaw.

Cracked teeth. Every dentist will closely examine every tooth to be treated during root canal, and will also carefully review dental images. Those careful examinations and inspections of dental imaging should reveal all cracks in the structure of an infected tooth. The reality is, though, that some cracks can be missed. Those cracks can eventually allow bacteria — if present in your mouth or jaw — enter the interior of the tooth and cause infection requiring a repeated root canal therapy.

Signs of a failed root canal

Sensitive teeth and gums, pain, and swelling is natural and normal after any root canal therapy, even treatment that succeeds. However, those post-surgery characteristics should gradually improve and ultimately resolve, usually within two weeks of the procedure. If, however, those symptoms increase rather than decrease or persist rather than resolve, those persistent symptoms may indicate potential failure.

Additionally, it’s important to keep in mind that signs of root canal failure can arise weeks and months after the completion of the original root canal procedure. Coronal leakage, for example, may occur at any time after the crown leaks which may not occur until long after the original operation. Whenever you notice any symptoms of a tooth infection or failed root canal procedure in a previously treated tooth, you should contact your dentist in Flagstaff as soon as possible.