There are several root canal complications that can crop up!
The first complication is identifying exactly which tooth is the one causing the problem.
Sometimes it can be notoriously difficult to be sure. It can feel like the pain is coming from a different tooth to the one that is really the cause.
This is when your dentist has to use all his detective skills!
The next complication involves teeth that have crowns ("caps") on them. Sometimes, the tooth under the crown is actually tilted or twisted, but the crown has been made to make it look straight. This means the tiny space inside the tooth will be in a different location than the shape of the crown suggests. The dentist must assess this carefully before he starts!
Different teeth have different numbers of roots. For example, molars usually have three roots. But inside the 3 roots there can be 4 or 5 root canals. And they can be partly hidden! The dentist must make sure that he finds all these tiny canals, otherwise there is a chance that bacteria could get back into the tooth and cause infection.
Although most front teeth have straight roots, the teeth towards the back of your mouth (the molars) usually have curved roots. It can be difficult to treat a tooth with curved roots, because the dental instruments have to be bent by hand to match. There is a small risk of the instrument breaking inside the root canal. And some roots even have a double curve - we call it "S" shaped!
One of the less common complications is calcified root canals. As you get older, the tiny spaces inside the root (the canals) gradually get smaller. At some point, they can become completely filled in or blocked, leaving no space behind. This is called a calcified root canal. It can be extremely difficult to treat a calcified canal.
Some teeth have very long roots, and therefore very long root canals. These can be over 3 centimeters in length. Again, this makes treatment more difficult.
And finally there are complications that arise due to the patient as a whole.
Sometimes a patient cannot open their mouth very wide, or they just have small mouths. Other patients can become restless during treatment, constantly moving their head. That can make doing a root canal rather like trying to mend a small watch while being tossed about, sitting in a small boat at sea!
These are just some of the root canal complications that dentists can be faced with. There are others, but these are the main ones. Now you can see why doing a root canal is a real challenge for the dentist!