Beneficial effects of air inclusions on the performance of ethylene vinyl acetate (EVA) mouthguard material

Abstract

Objective: To investigate the impact characteristics of an ethylene vinyl acetate (EVA) mouthguard material with regulated air inclusions, which included various air cell volumes and wall thickness between air cells. In particular, the aim was to identify the magnitude and direction of forces within the impacts. Method: EVA mouthguard material, 4 mm thick and with and without air inclusions, was impacted with a constant force impact pendulum with an energy of 4.4 J and a velocity of 3 m/s. Transmitted forces through the EVA material were measured using an accelerometer, which also allowed the determination of force direction and magnitude within the impacts. Results: Statistically significant reductions in the transmitted forces were observed with all the air inclusion materials when compared with EVA without air inclusions. Maximum transmitted force through one air inclusion material was reduced by 32%. Force rebound was eliminated in one material, and reduced second force impulses were observed in all the air inclusion materials. Conclusion: The regulated air inclusions improved the impact characteristics of the EVA mouthguard material, the material most commonly used in mouthguards world wide. M outhguards are worn by participants in contact sports to reduce damage to the orofacial complex. As well as providing protection to teeth against chipping, fractures, displacement, and avulsion, mouthguards can reduce the incidence of pulpal damage caused by impacts. Research has shown that soft tissue injuries, jaw fractures, and concussions are also reduced in those who wear mouthguards in sports that involve heavy body contact and possible impacts from sports equipment.

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

“…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.…”

Prospects for the use of intra-oral simulators in the sphere of sports

“…Стоматологическое здоровье населения в XXI ве-ке предполагает предупреждение и контроль за раз-витием воспалительных заболеваний пародонта бла-годаря усовершенствованию коммунальных методов профилактики на основе развития личных методов стоматологической гигиены и просвещения [1,2].…”

Behavior under impact of two polyvinyl acetate-polyethylene (PVA-PE) polymers and one elastomer-application to custom-made mouthguards

“…It was found that polyvinyl acetate-polyethylene (PVA-PE) materials provided higher absorption than polyurethane and latex. Furthermore, the inclusion of air bubbles in the material lowered the transmission of the forces from an impact on the patient's jaw 16,17) . At this juncture, it must be mentioned that these tests were conducted either on plates or mouthguards, whereby the latter were thermoformed either on a jaw model [19][20][21] or on actual jaws 12,22,23) .…”

“…At this juncture, it must be mentioned that these tests were conducted either on plates or mouthguards, whereby the latter were thermoformed either on a jaw model [19][20][21] or on actual jaws 12,22,23) . Most of the studies measured the force transmitted by the materials as a function of time 13,[16][17][18]21,22) . However, the study of other material behaviors could be useful for mouthguard application.…”

“…As such, this property of the materials used to make custom-made mouthguards must be optimized to fulfill the purpose of providing maximum protection. To date, a number of studies have been conducted on transmission of impact forces versus force absorption [13][14][15][16][17][18] . It was found that polyvinyl acetate-polyethylene (PVA-PE) materials provided higher absorption than polyurethane and latex.…”