If you grind your teeth at night, you aren’t alone. Many people have Bruxism, a condition that causes the jaw to be overactive at night, resulting in teeth grinding. Bruxism can be the result of physical, psychological, and genetic factors. When untreated, it can cause loose, missing, broken, or chipped teeth. Jaw pain, ear pain, headaches, soft tissue damage, and temporomandibular joint disorders may also occur as a result.