A mouthguard is a protective device for the mouth that covers the teeth and gums to prevent and reduce injury to the teeth.
A mouthguard is most often used to prevent injury in contact sports, as a treatment for bruxism or TMJ, or as part of certain dental procedures, such as tooth bleaching.
Generally, mouth guards cover your upper teeth only, but in some instances mouth guards can be made for the lower teeth as well.
If you grind your teeth at night, a special mouth guard-type of dental appliance called a nocturnal bite plate or bite splint may be created to prevent tooth damage.
An effective mouth guard should be comfortable, resist tears, be durable and easy to clean, and should not restrict your breathing or speech.