The movie Marathon Man has a scene in which a man is tortured by doing a root canal treatment (endodontic treatment) without novocain. This scene seems to characterize the great fear people have of this treatment. However, I have performed hundreds of root canal treatments and have had four done on myself. (And I am a very anxious dental patient.) I can tell you that root canal pain—pain during the procedure—this is the exception, not the rule. And root canals are not really traumatic—there isn’t a lot of grinding as there is with a filling or a crown. Most of the work is done with small, quiet hand instruments. Sometimes the tooth itself is dead inside, so there isn’t even any novocain required. Root canal treatment prevents and solves toothache pain—it doesn’t cause it. Tooth extraction is much more traumatic. It saddens me when people elect to have a tooth extracted rather than saved because of a fear of root canals. The traumatic tooth extraction appointment only reinforces their fear of dentistry, and then they are without their tooth. Read our page about what to expect when you need a root canal procedure.
But pain after a root canal is a different story. Let’s explain that pain, why it happens, and what to do about it.
Why Root Canal Pain?
There are two possible sources for a toothache:
One source of toothache pain is the inside of your tooth. When you first begin to have a toothache, this is usually its source. The tissue inside your tooth becomes infected from deep decay or trauma, and it hurts.
The other source of toothache pain is the ligament that attaches the tooth to the bone. When you have an infection inside your tooth, it will eventually spread. It leaves the tooth through its apex where it infects the bone around the end of your tooth. Pain after a root canal treatment almost always comes from this source—from the ligament surrounding the tooth. If the tissue inside the tooth has been completely removed, including the nerve inside your tooth, it is impossible for the pain to be coming from this source.
When you first get a toothache, the more promptly you seek treatment, the less likely you are to have pain after the treatment. Here is why: When your tooth is infected, the longer you allow the infection to spread, the more difficult it is going to be to eradicate that infection. If the infection is entirely inside your tooth, it can be completely removed. However, if it has spread to the bone, only the source of the infection can be removed—your body has to take care of the rest.
When a dentist performs a root canal treatment, he or she will remove all the soft tissue inside the tooth. Some of this tissue will inevitably be pushed out the end of the tooth, through the apex and into the bone. The more infected your tooth is, the greater the potential irritation from this. Or, the instruments your dentist uses can penetrate the apex and thus irritate this tissue.
When this happens, your tooth will hurt afterward. This doesn’t mean the dentist did anything wrong. In fact, some prominent root canal experts insist that if endodontic treatment is done properly, there will always be some discomfort afterwards.
What to Do about Pain after a Root Canal
There are a couple of ways that a dentist can minimize this post-operative pain. One way is to reduce the tooth being treated so that, after the appointment, you won’t be able to touch the tooth when you clench together. This is a very effective technique and I would do this routinely after root canal treatments. A second way to address it to take an anti-inflammatory medication, such as ibuprofen, usually at the beginning of the appointment. The body’s inflammatory reaction tends to cause the tooth to swell up a little, making you hit this tooth harder than any other tooth. This can lead into a vicious cycle of pain, more swelling, and more pain. So taking an anti-inflammatory medication before the appointment intercepts that cycle.
If you do experience pain after root canal treatment and you are unable to clench your teeth together without pain, visit your dentist as soon as possible. Simply reducing the tooth so that you don’t hit it breaks this pain/inflammation cycle and can produce immediate, seemingly miraculous results.
Taking antibiotics after a root canal treatment could be necessary. If the infection that was inside your tooth has spread at all to the bone around the apex, then antibiotics will help you heal.
If a tooth that has had endodontic treatment has pain that is aggravated by cold temperatures, this is completely different. This type of hurt comes from inside the tooth. It indicates that there is still living tissue in your tooth. It could be that there is an extra canal in the tooth that wasn’t visible to the dentist. Go back to your dentist and have him or her do tests and x-rays to try to determine the source of the problem.
Delayed Root Canal Pain
If your tooth heals and feels normal and then later begins to hurt, it probably indicates a failed root canal, and re-treatment or root canal surgery may be required to save the tooth. This doesn’t happen too often.
And sometimes, nothing seems to work and a tooth needs to be extracted.