Fractured teeth, neck injuries and abrasions in the mouth, also known as sports-related dental injuries, are ever present among athletes. According to the U.S. Centers for Disease Control, sports-related dental injuries account for more than 600,000 emergency room visits each year.

One may assume that mouthguards should serve as a preventive measure. In some 200,000 cases annually, mouthguards have been known to avert oral injuries and cut the risk of concussion by 50 percent. However, while a mouthguard may be popular for its ability to prevent the injuries that may temporarily and sometimes permanently disfigure a person's appearance, what many may not be aware of is the importance of proper maintenance, cleanliness and care to prevent disease transmission and infection.

According to a study that appears in the September/October 2007 issue of General Dentistry, the AGD's clinical, peer-reviewed journal, mouthguards harbor large numbers of bacteria, yeasts and molds that can possibly lead to life and/or health-threatening infectious/inflammatory diseases.

"Everything that a microorganism needs to survive, including food and water, can be found in a mouthguard," says Thomas Glass, DDS, PhD, lead author of the study. "While mouthguards appear solid, they are very porous, like a sponge, and with use, microorganisms invade these porosities."

"These concerns are similar to using an infected toothbrush repeatedly or using silverware that has not been cleaned properly," says AGD spokesperson Bruce Burton, DMD, MAGD, ABGD. "Although a mouthguard is recommended to prevent permanent damage to the mouth and teeth, we know it also has the potential to be a reservoir for bacteria that can cause gum infections or the bacteria that help promote tooth decay."

There are warning signs that can alert athletes that he or she may be suffering from a contaminated mouthguard. Those include "difficulty breathing, wheezing, diarrhea and nausea to the point of vomiting," says Dr. Glass. As a high school football coach for 25 years, Dr. Burton witnessed many poor habits athletes practiced when handling their mouthguard. "Chewing on the mouthguard until it no longer serves the purpose of protecting the dentition is one poor habit," says Dr. Burton. "In addition, some athletes throw the mouthguard in with dirty, sweaty gear and never clean it."

Mouthguard maintenance:

• Brush teeth before wearing a mouthguard.
• Never share a mouthguard with teammates.
• During sporting events, have a backup mouthguard.
• Purchase disposable mouthguards.
• Clean mouthguards before storing them.