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Extreme pain during root canal procedure, even after 3 shots of anesthetic


Butl Nor

Junior member
Dec 5, 2015
I had problems with my lower first molar for more than 20 years. It was drilled and filled many times, but I still wasn't able to fully chew on it, since it felt like "loose". However, a week ago it started to hurt a lot, so I went to the public hospital, where after taking a rentgen, they decided to do a root canal treatment on the tooth, although there was no sign of any inflammation, caries or decay. I got a shot of novocain, the lips felt numb, but during the procedure I felt EVERYTHING! The pain was more than I could bare, almost screaming. I got two more shots of anesthetic, without effect. I was twitching and sobing and sweating because of the pain. After half an hour the procedure was finished. In the evening and the next days it didn't hurt at all, although I didn't take any painkiller.

However, after 5 days I realized that even a mild accidental chewing on that tooth causes severe pain. Two days later I wasn't able to even eat sweets or drink cold water. The pain was unbearable.

So I called a commercial dentist, which has a good reputation and my friends were recommending him. I went there yesterday and after giving a mandibular anesthesia, he opened the tooth, saying that it doesn't seem anything wrong, but most likely the tooth wasn't thoroughly cleaned during the first treatment. So he repeated the root canal procedure. And again, the severe pain! He gave me two more shots, without effect. The lips and the jaw were numb, but why did I feel such a severe pain then? He said this is completely unusual. I asked him if I became resistive to novo/lidocain, but most likely not, as the lip was numb. The procedure took around 1.5 hours, so it was much longer than the first time.

In the evening, and during the night, no pain whatsoever, like the first time.

My question is, what do you think is the reason for such unusual pain during the root canal treatment? I have read that the inflammation cause prevent the nerve becoming numb, but I was being said that there was no inflammation, no abscess, no crack. Am I the only one in the world?
Re: Extreme pain during root canal procedure, even after 3 shots of anesthetic

Hi -

You're not the only one in the world! I have problems with the anaesthetic not working on lower teeth too - like you, my lips etc go completely numb (so the drug is working) but the actual teeth will still feel everything, just as you described. It is unusual, your dentist is right, but it's not unheard of.

Don't give in - there is hope - after about 15 years of searching and at least 4 or 5 different dentists trying I *finally* found one who was able to get those teeth totally numb. It's hard to describe just how much of a relief that was although I'm sure you can imagine!

What you need to look for is an dentist who is trained in advanced techniques with local anaesthetic, and is prepared to keep trying different things until they can get it numb. There are other things they can try - in my case, what worked was an intraosseous injection, although everybody is different so what works for you may not be the same as what worked for me.

I'm told that a possible cause in my case is extra nerve branches - basically just unusual anatomy - so the usual injection successfully numbs up the usual nerve as expected, but it doesn't touch the *other* nerve that is also supplying my teeth. (Note, not a dentist, just a patient, this is just my understanding of what they are telling me!)

All the best, I hope you find the answer! There will be one, don't give up!
Re: Extreme pain during root canal procedure, even after 3 shots of anesthetic

I have the same problem mouth goes numb after two shots but the pain is just excruciating. I've had 2 hours sat in the torture chair so far and have to go back again for an hour n half because the pain is just too much to bare. Last time my dentist asked me what the pain was like and I told him I've never felt pain like it it's so bad he couldn't understand why it was hurting so much. I will have to speak to him about a intraosseous injection at my next appointment. So cheers for that tip
Re: Extreme pain during root canal procedure, even after 3 shots of anesthetic

Hi! I hope it works out for you and they find the answer - let us know how you get on!
Re: Extreme pain during root canal procedure, even after 3 shots of anesthetic

Our advice to posters is not to let dentists/specialists work on you if you are not sufficiently numbed:

For root canals endodontists are more likely to care about their reputation and know the various advanced techniques for getting difficult teeth numb. Sometimes just a different type of local anaesthetic makes a difference.


Good luck. No one has the right to inflict pain on you during treatment to that extent.
I had a strange similar situation but mine occurred right after the procedure. It was really strange. All of a sudden bammo the same pain I was feeling all along prior to the root canal came back above the tooth. I was still fully numb. My doctor said it only occurs in about 10% of people. They then injected some numbing in the roof of the mouth off to the side and that stopped it. Unfortunately I have had ongoing unexplained pain.