Root canal treatment is a relatively common dental procedure that many Australians undergo every year. If you have damaged or infected tooth pulp, a dentist will need to remove the problem material and fill the space. Root canal work is often relatively quick and simple, but a dentist cannot guarantee success. Here are five scenarios when your root canal treatment could fail.

Branched canals

To get access to the root canal, your dentist must open the tooth through the flat part at the top. In this way, he or she can then get to the soft tissue (or pulp) in the middle of the tooth. The root canal is tiny, so the dentist generally needs to use several small files to open up and enlarge the space for a filling.

All teeth have at least one root canal. The front incisors and canine teeth have a single root and canal, but the back molar teeth have two or three roots, each with their own root canal. In some cases, the root canals branch off. It's very hard for your dentist to detect this, so he or she may only clean out the main canal.

In this instance, infected material may remain in the branched canals, and the problem with your tooth may persist. Your dentist may need to carry out further work to get to the infected material, or he may need to refer you to a specialist.

Narrow or curved root canals

As part of root canal treatment, your dentist will clean out diseased material using small endodontic files that he or she pushes into the canal. Your dentist will repeat this process several times during one course of treatment.

If the root canal is too narrow, your dentist cannot always get a file right into the diseased area. Similarly, curved root canals are also difficult to work with because the files are straight. Again, in this instance, you may need a specialist endodontist to help fix the issue.

Blocked root canal

Root canal treatments sometimes take place over multiple visits to the dentist, particularly if you have a serious infection. In some cases, debris from the first treatment will remain in the root canal. If your tooth then needs a second session, any blockage will make it almost impossible to use the tiny endodontic files during the follow-up appointment. 

With a blocked root canal, your dentist may need to carry out an apicoectomy, where he or she exposes the root tip through the gum. During the process, your dentist can surgically remove infected material, cleaning out the root canal entirely.

Cracked tooth

Teeth cracks aren't always easy to detect. Indeed, symptoms like pain when chewing or temperature sensitivity may often come and go. Teeth cracks are also often tiny, which means you can't see them in the mirror, and your dentist may find it equally difficult to find them during a routine check-up.

Unfortunately, a crack in your tooth can offer a home to unwanted bacteria, which can cause an infection. If a crack runs through the root canal, the work that your dentist does will often not fix the problem because the crack allows bacteria to reinfect the area. Cracks can also form after your root canal work, allowing the original infection to return.

Coronal leakage

After root canal treatment, your dentist will apply some form of seal to the tooth crown to stop anything getting into the root canal and causing an infection. If the seal isn't adequate, reinfection can occur. This problem can occur very quickly. Indeed, studies show that complete recontamination of the root canal can take place within three to six weeks. As such, if you leave a temporary solution in place too long, you can cause problems with the healing process.

Your dentist will talk to you about ways to permanently seal the tooth. The barrier he or she uses should stop any seepage into the root canal. Often, a normal dental filling is adequate, but you may also need a dental crown.

Thousands of Australians have root canal treatments every year, but complications can occur. If you're worried about treatment that you have had, talk to your dentist straight away, so he or she can help you fix the issue.