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Saturday, October 26, 2013



I have heard this question many times from new patients coming into the practise or from emergency patients having problems with a tooth.  Of course the answer is never simple and always depends on the circumstances.
When someone has had a root canal treatment the tooth is now altered and may not feel exactly the way it did before.  The questions we must ask:  Is the tooth functional?  Can you eat on it without discomfort?  If you answer yes to both then there is no problem.  If the answer is no then there is a problem and that is what we will deal with in this blog.
Lets start with the simple.  If you just had a root canal yesterday and your tooth is hurting it is most likely some post op discomfort and it will most likely resolve shortly.  You can even get some swelling after the treatment which may need an antibiotic but then will resolve.
What we really want to discuss here is the tooth that had root canal treatment a while ago and you still can't eat on it.  General success of root canal treatment is in the very high range.  If a root canal treatment does not succeed there can be a number of reasons which in general amounts to bacteria still being in the root canal system.  This can happen because there may be an extra canal (or two) which we didn't find.  It can also be because the root canal system is so convoluted that we couldn't clean out the entire root canal system well enough.  Another reason that a root canal may fail is due to a fracture in the tooth which may never have been noticed.
So probably the more important question in all this is what can be done?
This question usually involves a discussion with your dentist because the answer is not always black and white.  If the root canal looks like it was done poorly then you would consider redoing it.  The results could be very good.  If the root canal looks like it was done well then you have to consider the cost benefit of redoing the root canal or apical surgery (all in an attempt to stop bacterial leakage into the surrounding tissues) versus extraction and implant placement. I have simplified things but as I said earlier this will involve a discussion between you and your dentist as to the proper course of action depending on your individual circumstances.

Having fun doing Dentistry in Hamilton Ontario

All the best
Dr. Ron Barzilay

PS you are welcome to follow the blog and leave comments


  1. Hi, I am in Israel and I saw some of your posts online. I have a question for your kind assistance: About 4 years ago I had a root canal done on one of my front upper teeth. It has blackened somewhat, but that is not my concern. My dentist did NOT put a crown on it at all. Is that negligent? Will my tooth break eventually? Would really appreciate your feedback. Thanks you in advance,


    1. Harvey, yes I do know about Barzilai Medical Center in Ashkelon. No relation to me although I did practise for a number of years in Jerusalem. Nice to see that I am being read in Israel.
      Regarding your front tooth. You almost always need a crown on the back teeth after a root canal. This is because during the root canal treatment, a lot of tooth structure is destroyed and due to the direction of forces that goes on during the grinding of your food on the back cusps, these teeth are more likely to break after a root canal treatment. To prevent this we crown the posterior teeth.
      The front teeth are different. The force on these teeth go through the teeth longitudinally from the edge of the tooth to the root and therefore breakage is not a concern. In other words, the tearing that the front teeth do, does not dispose them to force that can generally break them as opposed to the grinding forces that can break the posterior teeth. Now there is a caveat here. Sometimes there is so much tooth structure destroyed ( for various reasons such as decay or trauma) that a crown is still required to replace the missing tooth structure.
      Harvey, I can only answer your questions in a general way as I have not examined you or taken x-rays of the tooth. your dentist negligent? I don’t think so. Will my tooth break eventually? I hope not but there are so many factors involved in that question I will say , probably not but who knows.
      Again Harvey, without actually examining I cannot give you real diagnosis and probabilities only guesses and possibilities. I hope that I have helped a little.
      All the best
      Dr. Ron Barzilay

      Oh yes, follow the blog if you get a chance and your comments are always welcome.