First of all, thank you everyone, for your support and suggestions. I can't tell you how much it means to have a place like this. My friends and family are very supportive, but cannot begin to understand what this feels like, so it's great to be able to come here where people "get" it.

And an extra, very big thank you to Bryanna, for taking the time to parse all my posts for answers. I'm sorry I haven't had a chance to post this sooner, but between work and an extra long visit to the dentist yesterday (he made me a new soft nightguard), there hasn't been any time. I'm also sorry I don't have x-rays to post, but I've been reluctant to ask anyone for them, as silly as that may sound. Anyone who's seen them seems to think they look fine, with no evident areas of infection past or present.

Yes, Bryanna, my gum is still quite sore, though the dentist thinks it looks healthy. Yesterday was a full week after the curettage and the first time I think I didn't feel the additional pain of that procedure. But the original, lingering pain is still there, so I am not sure the curettage worked? That area has been especially sensitive for a long time, and I think in fact was the cause of my thinking I needed a root canal (#1). After the root canal, everything felt worse, but what I really seemed to notice was that the irritated feeling in my gum was still there and probably even more inflamed. The endodontist and my dentist both pushed for a retreatment for that issue (none of which they charged for, to be fair) and I thought maybe the retreatments would solve the problem. (They were strung out of a couple of months, with the endo going in repeatedly and cleaning out more, and using calcium hydroxide, and a third "re-treatment" where the dentist himself opened up the tooth and used used some sort of laser to "sterilize" the tooth. )

But nothing helped. In the weeks following R/C #1 (which was on tooth 18, if that helps; R/C #2 was on 19), the gum got so inflamed it felt like it was trying to physically eject the tooth. It was obviously red and swollen and the dentist recommended some deep cleaning, which did seem to calm it down a bit, at least visually. Still I always felt like it was an open wound, and very sore. It seemed like I could feel liquids (not just cold liquids) following the path of my (ostensibly removed) nerve down to the (dead) root of the tooth. This is when I began to suspect the adjacent tooth (and had the second root canal).

Now, even though they are root-canaled and officially "dead teeth" I still feel substantial soreness in the gum surrounding 18, though the tooth itself no longer hurts. Tooth #19 is still very tender to the touch, though the dentist feels it seems better since he saw me two weeks ago. (Also, seemed more irritated by the new night guard which even though is soft, still allows me to clench.) For the TMJ, which everyone seems to agree I've developed, I am taking ibuprofen (3x/day), using warm wet compresses (whenever possible), doing some jaw exercises and have changed to a soft food diet. This is the place where I've seen the most progress in the shortest amount of time, so I'm hopeful this will help.

The teeth, on the other hand, I have lost whatever hope I had. I don't want to have crown lengthening surgery on a R/C tooth. There is no guarantee it would work, from what I understand, even if I wanted to keep this tooth, which I don't. I would like to have this tooth extracted, but I am still not sure that would solve the biologic width issue. (I assume because the tooth will be gone, the gum will just re-form, but I don't fully understand why this issue is causing me so much discomfort, even after I had the cerec crown removed and a temp placed. Why didn't that help?) Also, the dentist warned me that it is possible that some of my jaw issues may have been caused by all the deep nerve blocks i have had in this area, for all those R/C's and retreatments and crown preps. I still have the plunking chord issue, running along my jaw; it happens a few times every half hour or so. I am now worried about further damage, since I realize I will probably need more blocks for the extraction. I also realize there is no way they will let me pull both 18 and 19 at once, and I don't really have the money to do it. How should I try to manage this?

Sorry for the extra long post. I know many people on this site are in similar or analogous situations, and I hope someone can get something out of this information. I wish I had thought more about all these ramifications of what seemed (each time) like a pretty straightforward decision. And I really wish I had never met an endodontist. Bryanna, I would really appreciate your help with these questions!