I grind my teeth and clench my jaws. I have TMJ. I have had two dental guards, and both of them, I seem to take out when I am sleeping, I find them under my pillow, etc...........
So, I don't even bother with it anymore. But it sure makes me wake up with headaches.
As I wake up my teeth are clenched. For me it is STRESS that causes it.
Good Luck........Nikko