A splint is a guard that is worn at certain times of the day, usually at night, to reduce the amount of pressure from grinding.
Splints are designed to fit over the teeth. They prevent the upper and lower teeth from coming together. This makes it difficult for you to grind or clench your teeth. These devices take pressure off the jaw joints and muscles so they can relax and heal.
If your dentist thinks a splint would help you, he or she will determine when you should wear it (during the day or at night) and for how long. A splint should never be worn so long that it changes your bite. If a splint causes or increases your pain, stop using it and contact your doctor.