Clenching teeth?

[indysteel]

You could try it, they're pretty inexpensive, but my experience as well as most of what I read is that OTC night guards (like dentist made ones that aren't adjusted often enough) actually encourage bruxing and clenching, by throwing your bite off and inserting something "chewy" that responds to movement. The dentist-made ones are hard resin so the muscles "know" to back off when they encounter it.

This. I wouldn't use an OTC product without at least first talking to your dentist.