Many recreational activities and organised sports come with a high risk of facial injury, especially to your top teeth. They stick out more and so are more susceptible to taking the brunt of a blow. A mouthguard helps to cushion any impact to the mouth and will help reduce the risk of broken or knocked out teeth, as well as injuries to your lips, tongue and inner cheeks. Mouthguards are also useful in preventing teeth grinding during sleep. Grinding your teeth puts unnecessary stress on your teeth, wearing them down and making them more likely to break or get cavities. A mouthguard will prevent your teeth from rubbing against one another, removing the negative side effects.