Hi, I'm glad you bought up ther subject of chattering teeth, because the last time I went to the dentist and she was checking my jaw/bite, she told me to rest my top teeth on the bottom teeth and my teeth chattered that much that I couldn't do it. I asked the dentist what would cause the chattering and she said it was tension in my jaw. It sounds as if all your jaw problems are caused by the inability to relax too.
I have to remember to relax my jaw during the day as it is always so tense, and at night I wear a gum shield to stop myself grinding my teeth and also biting my tongue = one night I bit badly into my tongue = oh the joys of anxiety.
As a matter of interest, as I am writing this I tried to put my bottom teeth and my top teeth together and they are still chattering away.
I phoned my cousin after that trip to the dentist and got her to check her teeth and her chattered as well. Guess we a just a load of chatterers!!