Follow-Up: I have the same problem and have been living with it for years, believing it was stress. Now I am being convinced that it is malocclusion, or: my teeth are not aligned well and I grind my teeth because they are "searching" for a better resting site (which does not exist). I am now seeing an orthodontist who is going to give me a plate for a month or two in order to find out where my natural resting place is. Then he will fit me with braces to eventually give me a more natural resting area for my teeth to be more comfortable and stop "seeking". All this at age 45 but I am ready for all this to stop.