Teeth grinding is clinically referred to as bruxism. It is the act of consciously or unconsciously clenching you teeth either during the day or while you sleep. It is considered both a medical and dental problem because it affects both teeth and all of the structure near it, including the head.
People grind their teeth for a number of reasons, possibly because of stress or because one's teeth are not properly aligned with each other.
Although not a major health issue, it can bring about problems like mouth, jaw, face, and neck problems, broken dentures, missing teeth, and many others.