Some people grind their teeth usually while sleeping. This wears down the enamel. It is usually a stress related habit. To help protect the teeth from further enamel wear, a Bite Guard is recommended. It is also known as an occlusal guard. The Dentist takes impressions or moulds of your teeth. The Dental Lab makes a clear plastic appliance that fits usually over your upper teeth. The appliance or Bite Guard is worn while sleeping. This takes the force off your enamel to protect your teeth.