A night guard is a plastic dental appliance that worn over the top teeth. This blocks the force from clenching and grinding to reach the teeth. Many people clench or grind their teeth to the point of destructiveness. Most people are completely unaware that they do it, because often they do it while they sleep.
Bruxism is the medical term for forceful clenching and/or grinding of your teeth. It is considered a major cause of tooth problems. The action of grinding- where your upper and lower teeth move back and forth with great force against each other- causes your teeth to flatten. Allowed to persist, grinding causes temperature sensitivity, pain because the wear gets down to the nerve, cracks in the teeth, receding gums and eventually lost teeth.
Grinding can also cause migraine headaches and pain in the shoulders, neck, back and ears. People who suffer from night-time teeth clenching or grinding (bruxism) should wear night guards to help lessen wear and tear on the teeth and reduce the possibility of tooth fractures.