Easy fabrication of a new type of mouthguard incorporating a hard insert and space and offering improved shock absorption ability

Abstract

The positive effects of wearing a mouthguard have been indicated in various epidemiological surveys and experiments, and their usage appears to be increasing in many sports. However, many preventable sports-related dental injuries still occur even with the use of a conventional mouthguard. We have developed a mouthguard (the Hard & Space mouthguard) with sufficient injury prevention ability (more than 95% shock absorption ability against impact with a steel ball carrying 15.2 kgm 2 /S 2 potential energy) and ease of clinical application. This mouthguard consists of an outer and an inner EVA layer and a middle layer of acrylic resin (hard insert), with a space to prevent contact between the inner surface of the mouthguard and the buccal surfaces of the maxillary front teeth or teeth already weakened through prior damage or treatment. The purpose of this article is to describe the method by which the Hard & Space mouthguard may easily be fabricated. We believe that this new type of mouthguard has the potential to reduce sports-related dental injuries. OutlineThe positive effects of wearing a mouthguard have been indicated in various epidemiological surveys and experiments (1-5), and their usage appears to be increasing in many sports. However, many preventable sports-related dental injuries still occur despite the use of a conventional mouthguard. For example, in a study of NCAA basketball teams, although athletes wearing custom-made mouthguards sustained significantly fewer oral injuries than those who did not, injuries did still occur (1.16injuries per 1,000 athletic exposures versus 3.00 injuries per 1,000 athletic exposures, respectively)(6).It is clear that when the impact force far exceeds the protective capability of the mouthguard, injury will occur. This is particularly true in cases where the wearer has restored(7-9) or endodontically treated(10) teeth as the strength and resiliency of a treated tooth never returns to normal levels. Furthermore, if a dental implant (11) is used, the periodontal tissues become susceptible to secondary injury due to a high elasticity modulus. However, the ordinal impact power in sports is estimated to be smaller than that found in traffic accidents(12). Therefore, most sports-related dental injuries not only in sound teeth, but also in treated teeth are assumed to be preventable by use of an appropriate mouthguard with high shock absorption ability.Many studies have investigated new methods for improving the shock absorption capabilities of mouthguards. These have included use of air cells(13), Sorbothane(14), a metal wire(15), a sponge(16), and a hard material (17)(18)(19). Most of these studies showed that these materials or fabrication methods were effective. However, the results of these studies have not been clinically applied.The ability of a mouthguard to protect against frequent injuries, often caused by a direct blow to the teeth, is believed to depend on 3 factors: 1) its ability to absorb and dissipate the force of impact throughout the mouthguard materi...

Knowledge and attitudes about sports‐related dental injuries and mouthguard use in young athletes in four different contact sports—water polo, karate, taekwondo and handball

“…3,4 Risk of sports-related dental injuries during body collision and falls is six times higher than from work-related accidents and three times higher than from traffic accidents. 5,11,17,[22][23][24][25][26] showed that only 5.7% of handball players used mouthguards, while in this study, 14.5% young handball players used them. [10][11][12] The incidence of sports-related orofacial and dental injuries is in relation to the type of specific sport and the age of athletes.…”

“…Orofacial injury had been experienced by 58 athletes (25.3%), while 31 athletes (13.5%) suffered dental injury. 5,11,17,[22][23][24][25][26] showed that only 5.7% of handball players used mouthguards, while in this study, 14.5% young handball players used them. Most participants were aware of mouthguards for dental trauma prevention and considered them efficient for preventing dental injuries during sports activities, but only 94 (41%) used them.…”

Paired maxillary and smaller mandibular mouthguard for rugby player with malalignment

“…If greater protection is required for the maxillary anterior region, a specially designed ‘Hard & Space mouthguard’ with sufficient occlusion should be used.…”

“…Therefore, our goal was to overcome this problem by designing paired mouthguards as possible one solution. If greater protection is required for the maxillary anterior region, a specially designed 'Hard & Space mouthguard' (16)(17)(18) with sufficient occlusion (19,20) should be used.…”

Thinning factors influence on custom‐made mouthguards thermoforming

“…Necessary changes were made to the basic condition according to each material and the examination parameter. Namely, about influence of heating time, increase in heating time of 155 and 175 s was considered; about influence of air pressure, smaller values of 0.4 and 0.5 MPa were employed; about colour effect, black, neon yellow and white were compared with clear in 3‐mm‐thickness sheet; about thickness effect, 1 and 2 mm were compared with 3 mm in clear sheet; about material difference hard and soft, 1‐and 1.5‐mm‐thickness hard sheets which often use for making Hard & Space mouthguard were compared with Drufosoft. Regarding the vacuum thermoforming procedure, a sagged sheet distance of 20 mm from the original position was used referring to the report of Takahashi et al.…”