pain in teeth

I have had pain in my teeth now for about three months.  I had, had a root canal and the dentist wanted to wait till beginning of year before he put the crown on because of past experience.  I woke up one morning and that area in my teeth started to hurt.  I called my dentist right away and he said we should go ahead and prep for the crown and put a temporary on the tooth.  He said it might be from pressure built up in that tooth.  After a week I called back and said it still hurt.  He sent my to an endonitics specialist and the specialist after several tests said I had receding gums and exposed nerves and pasted my tooth.  After three days, the pain was still present, and I called my dentist again.  He said it looks like we need to do a root canal on the tooth the endo thought was bothering me so we did.  He said we would wait for the prep.  I called back a week later still in pain.  He had me come back in and ran a bunch of tests.  See it doesn't hurt to eat on either of the prepped teeth with temporary crowns, or to bite down on.  It only hurts mostly when I drink sweet drinks, like coffee with creamer.  After my dentist ran a bunch of tests, he finally took some cavity x-rays and found two, one in the middle of the tooth and one in the front of the tooth right next two the two root canal teeth with temporaries on them.  It has now been 4 days since he did the work, and I am still experiencing the pain.  I called again and spoke with his secretary, she thinks it might be the drinks are getting in up in my gums where the temporaries may not be fully closed off and causing this pain.  I can sleep through the night and eat with no pain.  The pain starts gradually while I am drinking my coffee and builds up.  I take a few advil and it stables it.  Sometimes it feels better after I brush.  I wear a night guard and the dentist has put me on a special toothpaste.  Is there any hope of me being free of this pain?  Help!!