(HealthDayNews) -- Protect your young athlete's mouth. Every year thousands of kids have teeth knocked out by a baseball, basketball, hockey puck or football.

According to the American Dental Association, mouth protectors or mouth guards could have averted most of these injuries. So buy your child a mouth guard and ensure it doesn't get stashed at the bottom of a locker by shopping for a good fit. Kids won't wear them if they're uncomfortable.

Here are some options suggested by The Children's Hospital of Philadelphia:

• Stock mouth guards: They are ready-to-use and inexpensive but often don't fit well.
• "Boil-and bite" mouth guards: These are also stocked on sports' store shelves but must be heated before first-use. This makes them pliable and they should conform to the shape of your child's mouth.
• Custom mouth guards -- They can be made by your child's dentist. They'll fit the best but cost the most.