FRIDAY, June 11 (HealthDay News) -- It is just a small, basic piece of safety gear, but a mouth guard is essential for anyone participating in organized sports or recreational activities, the American Dental Association advises.

One study found that people who wear a mouth guard are nearly two times less likely to suffer an injury than those who don't wear a mouth guard.

"But you don't have to be on the football field or in a hockey rink to benefit from a properly fitted mouth guard," American Dental Association (ADA) consumer advisor Dr. Matthew Messina, a Cleveland-area dentist, said in an ADA news release.

"Findings in sports dentistry show that even in non-contact sports, such as gymnastics, mouth guards will help protect participants, and many experts recommend that everyone -- from children to adults -- wear a mouth guard during any recreational activity that might pose a risk of injury to the mouth, including practice and training sessions," Messina added.

Custom-fitted mouth guards are considered by many to offer the best protection, but other mouth guards -- such as mouth-formed "boil-and-bite" types -- can be effective if they fit well, are worn properly and stay in place, the experts say.

A mouth guard should be durable, tear-resistant, comfortable, easy to clean, and not restrict speech or breathing. Most mouth guards cover only the upper teeth, but mouth guards can also be made to protect the bottom teeth, according to the news release.

In time, mouth guards wear out, so it is important to check their condition and replace them before they become ineffective. They should also be replaced if they develop holes or tears, are too loose, or irritate the teeth or mouth tissues, the ADA suggests.

More information

The American Dental Association has more about mouth guards.