I heard the same thing when I had a root canal done on my back lower left tooth (not the wisdom tooth). The darn thing hurt for a year after and I finally had it pulled. The oral surgeon told me he should pull the one above, too, but I declined.
That was 10 years ago and my upper tooth is just fine. I have very dense and hard bone and it held just fine. It's still fine and I have had no problem with it at all.
The tooth that was pulled had a crack in it and would never have gotten any better. Because it was the last tooth I didn't worry about it drifting forward as most other teeth would have (they try and close a hole in the line).
It's really impossible to see a crack unless the tooth is pulled so that may be your problem.
If I had to do it over again I think I might have gone for an implant back there, though, although I haven't had any problems. I have had four implants on the top front and my DH has molar implants that have worked just fine. If you worry about the tooth above it an implant serves as a normal tooth.
Best to you on whatever you decide.
Well If its really hurting badly then why not to pull that out, regarding money its of-course a bit of worry but try out for something else maybe it will help, I will contact my dentist for your problem and then let's see what he has to say about that.
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