This might be simplistic, but it might help, it helped me. My dentist gave me a Plackers Dental guard for my grinding. Also after using this disposable device my headaches abated, also my tooth pain. I stopped for a while and my headaches and severe tooth pain returned so much so I posted here about possibly losing my last, top right molar. A few nights of using the mouth guard and all is well.

Some dollar stores carry the Plackers night guard.