Teeth grinding, clenching, or as it is called in the medical jargon - bruxism, is a phenomenon in which, usually during sleep, one presses the jaws so intense that it can result in wear and damage to the teeth. Other symptoms of bruxism are enlarged and sore jaw muscles (masseter muscles) and, not infrequently, morning headaches which occur independently or as part of a migraine or tension headache.
Factors that trigger bruxism is usually stress and anxiety, but also alcohol, smoking, certain drugs and some neurological diseases.

Treatment of bruxism consists of measures that eliminates / reduces the proclamation factors. Occlusal splints (also termed dental guards) are often used to protect the teeth.
Botulinum toxin has recently become an important and effective treatment against bruxism. Injection of small amounts of this substance in the jaw muscles, force them to relax, work less, which can prevent dental injuries, sore jaw and headaches. It can also make the use of dental guards unnecessary.