Bruxism was usually attributed to stress, but authorities today believe the cause may be an unconscious effort to correct irregularities of the chewing surface of the teeth. About 1 in 20 adults and 3 in 20 children unconsciously grind their teeth at night. This is called malocclusion. If you grind your teeth, you can exert thousands of pounds of pressure per square inch on the surface of teeth, which can cause headaches, affect supporting bone, gums and the jaw joint. To correct this, your dentist may fit you with a plastic night guard to help prevent further damage.