root canal done wrong! What should I do??Please read detail below for story...?

May, of this year, I paid cash for root canal. I recently started getting dental insurance and old dentist did not accept my insurance so I went to a new dentist. My new dentist have done quite of bit of work for me now and have prepared me for the crown for the root canal the old dentist did. But my insurance called and told me that the coverage would be denied because the root canal done in may was not complete as told by my xrays. I fear if the root canal has to be redone I will lose the tooth. After my new dentist prepared it, barely any tooth is left. But why didnt my new dentist notice the incorrect root canal?? Should I tell my old dentist what is going on?? do i let my new dentist fix the problem, could this be dental malpractice in need for a lawyer, especally if i end up losing the tooth? If not could I at least get my cash back for a root canal that was not even done right? should I go to a new dentist all together??
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Are you 100% positive this is a root canal done wrong? Did your insurance company do the root therapy? Are you having any problems with the tooth since the root therapy was completed in May? Are you really having any problems with either of the dentists that have been treating you? If the answer to the above questions are all "no", then your have a problem with your insurance carrier. They are quite crafty at finding reasons to deny claims, so I'd find out why they are denying the claim. Ensure they have the proper x-ray of the tooth with the root therapy completed. I really doubt that both your previous dentist and your new dentist are in cahoots trying to hide an undone root canal from you. Either one or the other would have said something. It always amazes me at how quickly patients will want to find fault with their doctor or dentist when they hear from their insurance company. The insurance company doesn't know a thing about doing dentistry. They do know a lot about how to deny claims. So forget about a lawyer and get right on the phone to your insurance carrier and get to the bottom of this. It's your coverage! They owe it to you! By the way, there is no requirement that a tooth has to have a root therapy before you need a crown. After you have had a root therapy the tooth needs the proper support with a crown so it seems as if both dentists were doing the right treatment for you. Best of luck and go get 'em! (The insurance people that is.)
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