IT'S THESTUF:P ESPNPRODYCERS DREAM OF. SKATING AT FULL SPE;ED, hockey player Eric Lindros takes an opponent's elbow. to the head .
. Quarterback Troy.Aikmen gets sacked, and his helmeted head bounces off the artificial turf. Centerfielder Johnny Damon knocks heads with a teammate shagging the same fly ball. These on-field collisions can make for dramatic footage, but they can also result in the enigmatic brain injuries known as concussions, the long-term consequences of which
Neurologists are only now beginning to understand.
PHOTOS BYMAHK OSlOW
r. Gerald J. Maher, D73, a temporomandibular joint (TMJ) specialist who counts the New
England Patriots among his patients, has developed
a mouth guard that could help prevent concussions among athletes of all ages-whether they play at Gillette Stadium or the local high school gymnasium.
AN INVISIBLE INJURY
More than 300,000 Americans sustain sports related concussions each year, according to the Centers for Disease Control. One hun-
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dred and sixty of those brain injuries happen to National Football League players, the league told The New York Times in 2000, and about two-thirds of all NFL players will suffer at least one concussion over the course of their careers.
Concussions occur when the head decel*erates rapidly-as in a collision or fall causing the brain to ricochet against the inside of the skull. Microscopic tears to the blood vessels or nerve fibers disrupt the brain's normal function, and the victim may lose consciousness, suffer headaches, feel nauseated or vomit, or experience problems with memory, sight, speech or other cogni- tive functions. Family members might even notice changes in personality.
Other than rest, there is no treatment for these impairments, which can persist for long periods of time-or they may not appear for days or weeks after the initial injury. Moreover, statistics indicate that an athlete who has suffered one concussion is at increased risk of sustaining another one. A second blow to an already-concussed brain can cause severe permanent damage or death. Multiple concussions, researchers suspect, can lead to severe cognitive impairments as well as Parkinson's and Alzheimer's diseases.
THE GLASS JAW
But how can a mouth guard prevent a brain injury? Maher became interested in that question when his friend and patient, mid*dle-weight boxing champion "Marvelous" Marvin Hagler, asked him about the phe*nomenon known as glass jaw. Some boxers can be brought down for the count with a single well-placed blow to the jaw, Hagler observed, while the same hit leaves other opponents unscathed. Maher started exam*ining all the fighters at Petronelli's Gym in Brockton, Mass., where Hagler trained.
''As a TMJ specialist, I knew what was going on was reasonably simple;' says Maher, a wrestler and marathon runner himself.
In a normal TMJ, the parts of the lower and upper jaw are aligned, and the cartilagi*nous disc between the two bones absorbs the energy of an upward blow to the jaw. In glass jaw, however, the parts of the joint are mis*aligned. An uppercut to the jaw slams the bony prominence of the lower mandible directly into the base of the skull, effectively scrambling the temporal lobe. This mis*alignment-technically called "internal derangement"-can be caused by stress*induced jaw clenching or grinding, and Maher estimates it occurs in as many as 65 percent of all adults.
Dentists have encouraged the use of mouth guards in athletics at least since 1964, when Jack Stenger, D.M.D., published an article in the Journal of the American Dental Association documenting that mouth guard use dramatically reduced injuries, including concussions, among
Notre Dame Football players. The ADA esti*mates that mouth guards prevent more than 200,000 Orofacial injuries to football players at all levels each year.
However, the mouth guards most of us used in high school-painstakingly molded with boiling water from our mothers' tea pots-are unlikely to help prevent concus*sions. For one thing, those bulky do-it-your*self mouth guards make it difficult to breathe or talk to teammates, meaning that many athletes--especially NFL athletes who are not required to-won't use them at all.
Even if they do make it into an athlete's mouth, most over-the-counter models don't go far enough back in the mouth to ensure proper TMJ alignment. And some guards can actually increase the risk of concussion by creating such smooth surface between
the upper and lower teeth that the lower jaw can slide back and up into the temporal bone with even greater force.
Maher's device is specifically designed to prevent concussion. Made out of custom fit acrylic, the Maher Mouth Guard covers only the back molars, allowing for comfort*able breathing, speaking and even drinking. By keeping the TMJ in proper alignment that is, with the mandibular condoyle below the thickest portion of the temporal bone-the device ensures force from a blow to the jaw dissipates in the jaw-and not the skull.
. As the dentist for the New England Patriots since 1980-recommended to the team by Dr. Stenger himself-Maher drives to Foxboro every Friday during the season to make sure everyone is in good shape for
Sunday. About 40 of the 53 Patriots, includ*ing the entire offensive line, choose to wear Maher's mouth guard. Not one of them has sustained a concussion from a blow to the jaw since they've been wearing the device, and the Patriots have the lowest concussion rate in the league. That's anecdotal evidence, but an indicator that Maher's design works as it should.
CHANGING THE RULES
What the Maher mouth guard won't do, however, is protect the teeth. That's not a problem, Maher says, because today's hock*ey, football and lacrosse helmets are equipped with cages that prevent injury to the lower face.
"That's not the job of this mouth piece;' he says. "The vast majority of athletes are not concerned about that because 'of the cage. But the NFL is very, very concerned about concussion."
In fact, the NFL is so concerned that the league invested more than $3 million into developing helmets designed to cut down on concussions. But the league currently doesn't require athletes to use mouth Guards. In part because there is no good data proving their use reduces concussion
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Maher hopes to provide the data that will change the league officials mind. This spring he applied for a research grant from the NFL to test his design’s efficacy in preventing concussions.
''I'm hoping to work with them and look at two college teams;' says Maher, who thinks the NFL is overall doing a good job protect*ing its players. "They are dealing with huge people who can move very fast. Concussions have gone up, but that's because we're better at recognizing them. Twenty years ago, no one was talking about this."
In the meantime, Maher is working to educate his colleagues about the benefits of his mouth guard by certifying other dentists to recognize susceptible patients and how to use the appliance.
"I explain what I've learned over the last 25 years," Maher says, "so doctors can avoid some of the pitfalls." He provides the tute*lage free of charge. Interested dentists can call 781-883-4434 for more information on the DVD training program or go to www.Mahercor.com. TDM
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