What is Bruxism? If you find yourself waking up with sore jaw muscles or a headache, you may be suffering from bruxism the grinding and clenching of teeth. Bruxism can cause teeth to become painful and sometimes parts of the teeth are literally ground away. Eventually, bruxism can destroy the surrounding bone and gum tissue. It can also lead to problems involving the jaw joint, such as temporomandibular joint syndrome (TMJ).