Should I pay if I had to go back to same dentist under great pain for my same tooth at the 3rd time????

My tooth is very sensitive for cold drinks. So my dentist did some fillings for me. That's my 1st visit of him. Then I had to go back because of pain and the tooth is still sensitive in 6 days. So he cleaned out all the fillings, and did a filling work again. Unfortunately, it's getting worse. The same tooth is under such a great pain so that I have major headache on the same side of my head. Also, I can't eat properly anymore because I got canker sores after my 2nd visit inside and out of my mouth. I went to see another dentist close by, he told me in order to save my tooth. I have to get my nerves out which will cost about $1000. Also, after the first 2 visits, I have already maximize my dental insurance. So any other expense from now on will be on my own untill next year. So my question is, should I get charged if i go back to the same dentist the 3rd time!?? What if I have to go back the 4th time?? Should he reverse the charge??? What should I do??? HELP!!!!!!!!!
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OK, take in mind that I am answering without having your chart in front of me to review, or your x-rays. It is likely that you really needed the rootcanal (Having the nerve removed) from the get go. Sometimes, the need for a rootcanal is not obvious. It isn't like a broken bone, where you can see the obvious problem on the x-ray. There are many different things that would require a rootcanal to be done. Cracks in a tooth is one of them. It is possible that you have a crack in the tooth, that is not going to be visible by the naked eye or on an x-ray. That could have been what caused you the sensitivity in the first place. Now, do I feel he was wrong to try a filling or even to try to redo the filling? No, because that was the most conservative treatment that he could do. However, if this were done in my office, this is what we would have done. You would have been charged for the filling. However, we would not have charged you for redoing it. If after that, the problem continued or worsened, we would have credited what was paid on the filling towards the rootcanal. Obviously you would have had an additional copayment due, but you would have been able to credit all you had paid for the filling towards that rootcanal. But every dentist does things his own way, so I can't tell you what they will do.
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