How can i tell when i grind my teeth at night?

Soreness: You can tell if you have soreness in your TMJ or certain teeth in the morning. If there are no soreness, you can also check by seeing if there are worn down cusp tips on your teeth. If your teeth look flat on the biting surfaces, you grind and need a night guard.

Sore facial muscles: Best is to have someone sleep next to you report it! ok so in the morning if you have soreness in the jaw muscles, or feel tightness or when you open and close your mouth it feels a bit sore, you could be grinding teeth.