Hello doctor, I got a root canal and crown several years ago in two molars, one on each side of my jaw. The crowns are metal with light porcelain on the outside. The teeth have felt fine ever since, until a few days ago. Now I feel pain in the right molar tooth whenever some warm food touches it. The pain takes a second or two to come, it is not instant on contact. Cold food or drinks cause no pain, neither does chewing. The gums around the crowned teeth are irritated, and look like they are possibly pulling down away from the teeth as I can see the dark metal underpart at the gum line. The tooth on the left side does not hurt at all aside from the irritated look of the gums around it. After doing some reading, I think a possibility is that the root canal did not get all the pulp in the right side tooth, and that is now infected again. I do not currently have dental or medical insurance and it may be a few months later I can see a dentist. What can I do in the meantime to take care of the tooth? I also became aware that I grind and click my teeth a lot without realizing it, and possibly at night when I sleep. My front teeth all look worn down now. This is concerning me a lot. I looked into teeth guards for sleeping, but the ones I found in stores need to be heated and placed between teeth to shape them to my mouth, and with my current heat sensitivity I can not use them.
Hello. I have read your query and it is pretty much clear that the right molar with history of RCT (root canal treatment) is causing the pain. Now the causes of pain may be a re-infection or incomplete RCT, but there can be other causes as well. As you mentioned you have bruxism (teeth grinding), the tooth or in this case the RCT tooth is under continuous insult from the grinding habit. This may have also caused the injury to the surrounding tissues. A prosthetic crown or porcelain crown here if not in occlusion may also be another cause for the pain.  Now as you mentioned that you are having pain only on taking warm foods and liquid diet and the gums around the crown is receding (recession), it looks like you might be having tooth sensitivity in the nearby tooth due to the dentin exposure caused by recession. An x-ray of the tooth will make the things more clear as if a new RCT is required or you just need proper cleaning and fluoride toothpaste. If it is possible, do upload a picture of the tooth and also x-ray of the tooth. Meanwhile, I would suggest you to use fluoride-containing toothpaste and ultrasoft toothbrush. Do not scrub, clean your teeth and gums gently. Maintain good oral health.