Commentary: Role of Properly Fitted Mouthguards in Prevention of Sport-Related Concussion.

Abstract

For many years, some experts have speculated that if athletes wear mouthguards in contact sports, many sportrelated cerebral concussions might be prevented. The key reference for this position was a 1964 article in the Journal of the American Dental Association by Stenger et al.1 Many other positions on the subject were established, most significantly by Hickey et al2 in 1967 and by Chapman3,4 in 1985 and 1990. Although no controlled experimental study has confirmed or refuted the idea that a properly fitted mouthguard reduces the likelihood of sustaining a concussive injury, evidence is mounting that the device could play a significant role in this critical area of player safety. As sports and our culture evolve, the techniques of playing and coaching the activities improve. Today, there are more participants, both men and women, in recreational and organized sports. Players are bigger, stronger, and faster than their predecessors. The desire to win at all levels of competition, the number of college scholarships available, and the money professional athletes are making have created an environment more conducive for athletic injuries. With the new awareness and media attention being paid to such injuries, sport-related concussion is surfacing as a major concern. In addition to education, we can make the playing of sports safer for participants by changing the rules of the game and by improving or changing the equipment. It is to the improvement of the equipment that this paper is directed. My perspective comes from two unique positions. As a pediatric dentist over the years, I have used many different types of mouthguards with my patients. As a college football referee in the Mid-American Conference for 18 years, I have on-field observations of the types and quality of the mandatory mouthguards the players have been wearing. The four types of guards most commonly used are (1) stock over the counter, not mouth formed, (2) boil and bite, well worn, mouth formed, (3) cut-off, no posterior tooth coverage, and (4) custom fabricated over a model of the upper dental arch.5 Through my involvement with the Academy for Sports Dentistry, I have discussed concussion prevention with many colleagues, including Dr John Stenger, and I have been able to establish the type of custom mouthguards constructed for the Notre Dame athletes in the 1964 study.1 Over the past several football seasons, I have been directly involved with a series of ongoing studies investigating the role that properly fitted, pressure-laminated mouthguards can play in reducing concussive forces applied to the brain. The methods used in our studies follow the Academy for Sports Dentistry position statement for properly fitted mouthguards.6 The materials used were polyvinyl acetate copolymer (Dreve-Dentamid, Unna, Germany). Impressions were taken of the players’ upper dental arches, and the protectors were fabricated over the models. The materials were formed with heat and pressure using a Drufomat machine (Westone Labs, Inc, Colorado Springs, CO). The posterior thickness varied from 3 to 4 millimeters in thickness after the final fitting (Figure 1). Concussions result from the sudden acceleration or deceleration of the brain because of either direct or indirect (eg, rotational) forces. The strength of this force and its effect on the brain are directly related to the absolute value of the acceleration. From newtonian physics, acceleration refers to change in velocity, which is expressed in terms of units of time over units of distance: