Botox is tremendously effective in stopping unwanted facial expressions, such as frowning, by blocking the nerve input to the injected muscles. But weakening facial muscles is useful for more than just making one look better, Botox injections can also help one feel better as well. Facial pain from grinding one’s teeth, known as bruxism, can be dramatically improved as well. By injecting the large masseter muscles, muscle spasm is stopped and their bite pressures are reduced. This decreases facial pain and decreases excessive wear on the teeth as well.