Stressgard® Nighttime Dental Guard - The comfortable, easy-fit nighttime dental guard, was developed to address the needs of those who grind and/or clench their teeth. Grinding and clenching can cause damage to your teeth, chipped teeth, loose fillings and loss of emamel. The StressGard® Nighttime Dental Guard provides a cushion between your upper and lower teeth thus helping to protect them from the harmful effects of grinding and clenching.