There are two main reasons mouthguards should be worn.
Mouthguards protect your teeth against trauma if you are an athlete. That would include fracturing teeth, devitalizing teeth, and evulsing teeth. You want to protect them and a professionally made mouthguard solves that problem for you. In fact, mouthguards are required in many high impact sports, such as football, hockey and lacrosse.
In the evening while sleeping. many people experience bruxism and sleep apnea. Both are related in one way or another, and they can both cause damage to your teeth. Mouthguards are very, very instrumental in protecting your teeth. They preserve the outer structures of your teeth, the enamel portions of your teeth, so you don’t wear them down, break them and cause further dental problems.