A mouthguard is a specially made, rubber-like cover which fits exactly over your teeth and gums, cushioning them and protecting them from damage.
It is important to wear a professionally made mouthguard whenever you play sport that involves physical contact or moving objects. This includes: cricket, hockey and football – which can cause broken and damaged teeth; and American football, boxing and rugby – which can all cause broken or dislocated jaws. A mouthguard will help protect against these events.
Depending on your age, your mouthguard may need replacing fairly regularly. If you are still growing, new teeth will come through and move into position. So the mouthguard may become too tight or loose, and will need to be remade to fit the new shape of your mouth.
Adults may not need to have their mouthguards replaced quite so often. But they are like any other form of sports equipment and will suffer from wear and tear. It is recommended that you take your mouthguard along to the dentist when you go for your check-up, so it can be checked.