Bite guards are custom made mouthpieces and are constructed of clear acrylic to snap onto the upper or lower teeth. Their function is to prevent damage from grinding and clenching on your natural teeth. They also allow the jaw muscles to relax and one to wake up in the morning with a less stressed TMJ (jaw joint). The hard nature of this acrylic requires precise customization and adjustment by your dentist. Typically, these are indicated for TMJ problems, grinding, or clenching habits.