Hi, Mamanan! I have had tooth sensitivity on and off for years. I did have a "spell" where it went on for months. I avoided extremely cold and extremely hot foods and drink. They would send me through the roof! So, you are not alone.
Here is a link about TMJD and fibromyalgia. It does sound a lot like you. If you could work on relaxing more, doing the gentle stretches for the shoulder and neck, that may help some. Massage around your neck and jaw...gently. Also this link suggests heat or ice. I think I'd opt for a warm damp washcloth to put on the jaw to help the muscles relax.
Lastly, I would suggest taking extra calcium to keep your teeth healthy. With fibro, we can be lacking in vitamins. Also, 99% of calcium is stored in your bones and teeth. It helps keep both strong. I know I was deficient. I noticed several years ago that my teeth looked a little transparent...they were losing the solid whiteness. I just thought it was because I was getting older and my dentist never said anything about it. A little over a year ago I was diagnosed with osteoporosis! I had been taking calcium for 20 years but I wasn't absorbing it. I switched to Citracal with D (600 mg twice a day) and I take Evista for the osteoporosis and guess what? My teeth are white again! My body was taking calcium from my teeth and probably weakening them and perhaps making them sensitive. I don't know if there is a correlation or not, but I haven't had a problem with sensitive teeth since.
Here is a good link, by the National Institute of Health, about the importance of calcium.
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Fibromyalgia, Crohn's Disease, Ostomy, Diabetes, Autoimmune Inner Ear Disease, Osteoporosis
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