Thanks for putting up your question on Just Answer.
Firstly, thanks for writing the "timeline" ! I wish more patients described their problems
like you have.
To answer your query very simply, YES. You do require a root canal before a permanent crown. Sensitivity
after placement of white fillings
in back teeth is not uncommon. This occurence due to some inadeqacy in the way the filling was done. it might also be due to the fact, that the tooth needed the root canal in the first place.
I would have felt a lot happier, had i read the word" X ray" in your time line somewhere. That is the most reliable method of determining whther a tooth needs a root canal in the first place.
Going for a permanent crown without a root canal could be fraught with danger. Already, the nerves of the tooth have been irritated. If the tooth starts to "misbehave" after the crown is done, then the crown will have to be removed and a root canal done. The crown then might not fit back on again, and you might have to go in for a new crown.
And lastly, antibiotics are definately not subsitutes for root canals !!!
Seeing all that has already happened, I would advise you to change your dentist ASAP !!
Hope this answers your question. Feel free to contact me again for more information.
Good Luck !!!
If my answer has helped you, please click on the *ACCEPT* button and give me *POSITIVE FEEDBACK*.
A * BONUS* will be highly appreciated. This tells me that my advice was indeed beneficial.