Thickness and stiffness characteristics of custom-made mouthguard materials.

OBJECTIVES: The purpose of this investigation was to determine the thickness of different types of custom-made mouthguards after processing and the deformational changes after simulated occlusal loading. MATERIALS AND METHODS: Ten mouthguards were fabricated for the same dental arch using the following materials and processing techniques: Group I: vacuum-formed (4 mm), Colored Mouthguard; Group II: vacuum-formed (4 mm), Proform; and Group III: pressure-laminated (3 + 3 mm), Drufosoft. After processing, the thickness was measured in three places: lingual cusps of the first molar, distal marginal ridge of the first premolar; and facial of central incisor. The stiffness of each group was determined by applying a simulated clenching force to the first molar lingual cusp areas on an Instron test machine with a blunt probe. The corresponding penetration was measured with a dial gauge. Thickness and force-deflection measurements of the different mouthguard groups were compared using analysis of variance and post hoc tests. RESULTS: The mean thicknesses at the molar for Groups I and II were 1.55 and 1.52 mm, respectively, and were significantly smaller then the corresponding thickness for Group III (3.48 mm). The mean thicknesses at the facial of the incisors for Groups I and II were similar (2.05 and 2.06 mm, respectively), and were significantly smaller than the corresponding thickness for Group III (3.29 mm). Groups I and II demonstrated similar stiffness that was significantly higher than that for Group III. CONCLUSION: These results show that vacuum-formed mouthguards produced smaller thicknesses than the pressure-laminated mouthguards. The pressure-laminated mouthguards produced material thicknesses that were previously shown to be adequate to protect athletes from trauma.     

An improved mouthguard material

a modified mouthguard material which reduces transmitted forces is described. Tests showed that the inclusion of air cells in a 4 mm thick polyvinylacetate-polyethylene (EVA) copolymer reduced the effects of impacts of less than 10 KN when compared with a material of the same EVA composition and thickness. The EVA copolymer with air-inclusions is suitable for the construction of stock, mouth-formed and vacuum-formed mouthguards. The improved elastic properties of the modified mouthguard material properties of the modified mouthguard material reduced transmitted forces by 32 per cent when copared with traditional EVA mouthguard polymers of the same thickness.     

Effects of aging on the dimensional stability of custom-made mouthguards.

OBJECTIVE: The purpose of this investigation was to assess the effects of aging on the dimensional stability of vacuum-formed, pressure-formed, and pressure-laminated custom-made mouthguards. METHOD AND MATERIALS: A master model representing the dental arch was fabricated in acrylic resin. Two ethylene vinyl acetate thermoplastic materials were tested: Essix (regular) and Proform (prelaminated). The model was benchmarked in five places along the curvature of the arch. The model was used to fabricate 10 specimens for each of the following groups: 1 = vacuum-formed (3-mm) Essix; 2 = vacuum-formed (4-mm) Proform; 3 = pressure-formed (3-mm) Essix; 4 = pressure-formed (4-mm) Proform; 5 = pressure-laminated (3-mm + 2-mm) Essix; 6 = pressure-laminated (3-mm + 3-mm) Essix. Die stone was poured into the newly made specimens and measured. Aging of the specimens was simulated by reproducing cleaning cycles (48 hours' soaking in water at 60 degrees F and brushing 100 times with a soft denture brush in soapy water at 140 degrees F for 20 minutes). Die stone was poured into the aged specimens and measured. Initial and postaging measurements were compared. RESULTS: All specimens showed dimensional changes post-aging, mainly decreases. Pressure-laminated specimens showed the best dimensional stability. CONCLUSION: Aging induced various dimensional changes in mouthguards, depending on the materials and processing techniques used. Most of the dimensional change for all mouthguards occurred at the central incisor region, the most important area for the protection of the anterior teeth and the premaxilla. Pressure-laminated mouthguard specimens showed the smallest range of changes at the central incisor region, suggesting potentially improved fit, comfort, and protection.     

Mouthguard: a new technique for the partially edentulous patient

Over the last decades, several articles have corroborated the need of using mouthguards in sports activities, manufactured with ethylene vinyl acetate (EVA) as their main material. There are different mouthguards techniques used by dentists worldwide to prevent injuries. A technique has been developed to help athletes, especially the partially edentulous patients, who were not getting the proper protection. The mouthguard technique consists in making EVA fillings to improve the adjustment and esthetics of mouthguard used by athletes. It is the authors′ conviction that the technique may prevent injuries in sports activities without impairing the athletes′ safety and esthetics.     

Influence of pre-laminated material on shock absorption ability in specially designed mouthguard with hard insert and space

Purpose

We have developed a new type of laminated mouthguard, the Hard & Space mouthguard, which incorporates a hard material insert and a space to prevent contact between the mouthguard and the buccal surfaces of the teeth. The purpose of this study was to investigate the effect of this new design on shock absorption.

Methods

Three types of mouthguard (a conventional laminated EVA mouthguard and two 3-layer type “Hard & Space” mouthguards made of 1.8-mm or 3.0-mm thick pre-laminated material (Konbiplast) and EVA with a 1.0-mm space) were impacted. Shock absorption was measured by means of a pendulum type steel ball impact testing machine at impact distances of 10, 20, and 30 cm and a dental study model with strain gauges attached to the lingual surfaces and an accelerometer fixed to the maxilla.

Results

Distortion of the impacted tooth and acceleration of the model were significantly reduced by all types of mouthguard at all 3 impact distances. The effect of the mouthguard was remarkable in terms of tooth distortion: both thicknesses of Hard & Space mouthguard showed more than 90% shock absorption, compared with only approximately 55–78% with an EVA mouthguard. Furthermore, shock absorption with the thicker 3.0-mm Hard & Space mouthguard reached more than 95% at the highest impact power.

Conclusion

Within the limitations of this laboratory study, Hard & Space mouthguards showed significantly greater buffer capacity than a conventional EVA mouthguard in terms of tooth distortion at the 3 impact powers tested.     

Influence of different types of mouthguards on strength and performance of collegiate athletes: a controlled-randomized trial

Abstract – Background: Prevention of traumatic dental injuries relies on the identification of etiologic factors and the use of protective devices during contact sports. Mouthguards are considered to be an effective and cost‐efficient device aimed at buffering the impacts or blows that might otherwise cause moderate to severe dental and maxillofacial injuries. Interestingly, besides their role in preventing injury, some authors claim that mouthguards can enhance athletic performance. Thus, the purpose of this controlled randomized trial was to evaluate and compare the effect of two different types of mouthguards on the athletic performance and strength of collegiate athletes. Materials and methods: Eighteen college athletes ranging from 19 to 23 years participated in this study. Devices tested in this study included an over‐the‐counter boil‐and‐bite mouthguard (O‐Flow? Max Under Armour^®) (UA) and a custom‐made mouthguard (CM). Physical tests were carefully selected by the head athletic trainer and aimed at evaluating the strength and performance. The following sequence was carried out on each test day: (i) 3‐stroke maximum power ergometer test, (ii) 1‐min ergometer test, and (iii) a 1600‐m run. A random assignment was developed to test all three experimental groups on each test day. Following the tests, each athlete completed a brief anonymous survey aimed at evaluating the athletes’ overall satisfaction with each type of mouthguard. Results: Custom‐made mouthguards had no detrimental effect on athletic strength and performance and were reported by the athletes as being comfortable and not causing difficulty in breathing. In contrast, boil‐and‐bite mouthguards did not perform as well and were reported as being uncomfortable and causing breathing difficulties. Conclusions: Based on the results of this study, the use of custom‐made mouthguards should be encouraged in contact sports as a protective measure, without concern for any negative effect on the athletic performance of the athletes.     

Elite tae kwon do athletes' satisfaction with custom-made mouthguards

Abstract –  Mouthguards are considered by most authors to be an essential part of equipment for athletes participating in contact sports. However, there are few studies evaluating the satisfaction of the elite athlete with mouthguards. The purpose of this study was to evaluate the satisfaction of elite tae kwon do athletes with custom-made mouthguards in a period of 4 months. The subjects were 22 elite athletes (11 boys and 11 girls) aged between 15 and 17 years. Each athlete was provided with an individual mouthguard made of ethyl vinyl acetate (EVA) material. Using Visual Analog Scale (VAS) questionnaire, esthetic appearance, ability to talk and to breathe, kiyapping (yelling in tae kwon do ), oral dryness, nausea, stability, ease in fitting into the mouth, inclination to chew and overall satisfaction were evaluated. Respective values of boys and girls were also compared. One-way anova and paired sampled t -tests were performed for statistical analyses using spss 11.0 windows program. There was no significant difference in the level of satisfaction between the first week and fourth month values. Results also showed that the level of satisfaction did not change statistically between male and female athletes.     

Rugby athletes' awareness and compliance in the use of mouthguards in the North West of Italy

Abstract – Background: The prevention of dental injuries during full‐contact sports such as rugby is extremely important. Wearing a mouthguard can significantly reduce the frequency and severity of orofacial injuries, but it is not always used as athletes find it difficult to tolerate. The purpose of the present study was to determine the awareness and the extent of mouthguard use in a sample of young rugby athletes in the North West of Italy. Material and Methods: The athletes of four amateurs rugby teams based in the Province of Turin, Italy completed a questionnaire about playing history, current use and type of mouthguards, disturbs associated with mouthguard use, and general attitudes towards mouthguards. Results: Only 53.85% of the subjects reported wearing their mouthguard all the time both during training and games. The most commonly reported problem associated with using a mouthguard was the discomfort on speech, followed by difficulty in closing lips, adversely affected breathing, adversely affected swallowing and slipping sensation. A statistically significant association between patients <22 years and non‐use of mouthguards was observed. Conclusion: Limited knowledge about oral injury prevention and limited use of mouthguards were observed. The present study suggests that educational courses for rugby players and coaches to promote the use of mouthguards would be extremely important to reduce common complaints about these devices and increase their usage.     

Does hard insertion and space improve shock absorption ability of mouthguard?

Abstract – Mouthguards are expected to reduce sports‐related orofacial injuries. Numerous studies have been conduced to improve the shock absorption ability of mouthguards using air cells, sorbothane, metal wire, or hard material insertion. Most of these were shown to be effective; however, the result of each study has not been applied to clinical use. The aim of this study was to develop mouthguards that have sufficient prevention ability and ease of clinical application with focus on a hard insertion and space. Ethylene vinyl acetate (EVA) mouthguard blank used was Drufosoft and the acrylic resin was Biolon (Dreve‐Dentamid GMBH, Unna, Germany). Three types of mouthguard samples tested were constructed by means of a Dreve Drufomat (Type SO, Dreve‐Dentamid) air pressure machine: the first was a conventional laminated type of EVA mouthguard material; the second was a three layer type with acrylic resin inner layer (hard‐insertion); the third was the same as the second but with space that does not come into contact with tooth surfaces (hard + space). As a control, without any mouthguard condition (NOMG) was measured. A pendulum type impact testing machine with interchangeable impact object (steel ball and baseball) and dental study model (D17FE‐NC.7PS, Nissin, Tokyo, Japan) with the strain gages (KFG‐1‐120‐D171‐11N30C2: Kyowa, Tokyo, Japan) applied to teeth and the accelerometer to the dentition (AS‐A YG‐2768 100G, Kyowa) were used to measure transmitted forces. Statistical analysis (anova , P < 0.01) showed significant differences among four conditions of NOMG and three different mouthguards in both objects and sensor. About acceleration: in a steel ball which was a harder impact object, shock absorption ability of about 40% was shown with conventional EVA and hard‐insertion and about 50% with hard + space. In a baseball that was softer compared with steel ball, a decrease rate is smaller, reduction (EVA = ～4%, hard‐insertion = ～12%, hard + space = ～25%) was admitted in the similar order. A significant difference was found with all the combinations except for between EVA and hard‐insertion with steel ball (Tukey test). About distortion: both buccal and lingual, distortions had become small in order of EVA, hard‐insertion, and hard + space, too. The decrease rate is larger than acceleration, EVA = ～47%, hard‐insertion = 80% or more, and hard +space = ～98%, in steel ball. EVA = ～30%, hard‐insertion =～75%, and hard + space = ～98% in baseball. And a significant difference was found with all the combinations (Tukey test). Especially, hard + space has decreased the distortion of teeth up to several percentages. Acceleration of the maxilla and distortions of the tooth became significantly smaller when wearing any type of mouthguard, in both impact objects. But the effect of mouthguard was clearer in the distortion of the tooth and with steel ball. Considering the differences of mouthguards, the hard‐insertion and the hard + space had significantly greater buffer capacity than conventional EVA. Furthermore, hard + space shows quite high shock absorption ability in the tooth distortion. Namely, hard + space has decreased the distortion of teeth up to several percentages in both impact objects.     

Use of mouthguard rates among university athletes during sport activities in Erzurum, Turkey

Abstract –  The purpose of this study was to determine the attitudes of mouthguard users in Erzurum, Turkey. The participants' appreciation in the use of protective devices, such as mouthguards, during sport activities was also evaluated. In this study, a 10-item questionnaire was distributed to 50 coaches and a 10-item questionnaire was distributed to 768 university athletes of three different sport modalities (basketball, soccer and volleyball) in the Atatürk University Sport Competitions. The Sport Competitions are composed of 20 faculty, except the faculty of dentistry. The result of the coaches' questionnaires indicated that none of the athletes used mouthguards while participating in sports. Of the coaches, 64% had seen orofacial trauma in their athletes during sport activities and 76% believed that mouthguards prevented oral injuries. Of the coaches, 76% reported that university athletes should use mouthguards in sport activities. The result of the university athletes' questionnaires revealed that the mouthguard utilization rate was 0%. Of all players, 78.1% were males (age 17–29) and 21.9% were females (age 18–23). Of all players, 7.31% had suffered from one or more type of oral injury while not wearing mouthguards. The results indicate that in Turkey, the use of mouthguards is rare in sports. It should be a combined duty of dentists, sports physicians, and coaches to encourage the use of mouthguards during training and sport activities. Doctors and dentists need to recommend a more intensive education of students in sports medicine and sports dentistry.     

Properly fitted custom-made mouthguards

With an increase in sporting activities comes an increase in orofacial injuries. A properly fitted mouthguard has been shown to provide protection against orofacial injuries and trauma to the teeth and supporting tissues such as the lips, cheeks, and tongue. However, because it is not mandatory that all athletes (amateur and professional) wear a mouthguard, many do not for reasons such as fit, comfort, social stigma, and speaking constraints. Athletes prefer mouthguards to be comfortable, soft, and resilient, which is characteristic of a custom-fitted mouthguard. This article will review reasons athletes prefer not to wear mouthguards and advantages of a custom-made mouthguard, as well as describe a process to fabricate a custom-made mouthguard.     

Effectiveness of mouthguards in reducing neurocognitive deficits following sports-related cerebral concussion

Abstract – Although it is widely accepted that mouthguards decrease the incidence of dental injuries, there is a controversy among sports medicine professionals as to the effectiveness of mouthguards in decreasing the incidence or severity of sports‐related cerebral concussion (SRCC). While some experimental data suggest that this may be the case, there exist a number of reports suggesting that mouthguards do not serve this purpose. These conclusions have been drawn, however, without actually measuring the extent of neurocognitive dysfunction in athletes following sports‐related concussion. The purpose of this study was to determine whether mouthguard use reduces the neurocognitive and symptomatic impairments that follow an injurious episode of SRCC. Preseason baseline data were collected as part of an ongoing clinical program that uses a computerized neurocognitive test to assess various faculties of brain function and symptoms reported at the time of testing. Follow‐up testing from 180 student‐athletes who had sustained an SRCC was analyzed for the purpose of this study. These athletes were separated into one of two groups: those who reported using mouthguards and those who did not. Neurocognitive testing was accomplished using the Immediate Post‐Concussion and Assessment Test (ImPACT). Results suggest that neurocognitive deficits at the time of the athletes’ first follow‐up assessment did not differ between mouthguard users and non‐users, suggesting that mouthguard use does little to reduce the severity of neurocognitive dysfunction and onset of symptoms following sports‐related head trauma. However, an interesting finding in this study was that athletes experienced significantly lower neurocognitive test scores and reported higher symptom scores following SRCC regardless of mouthguard use. This emphasizes a thorough clinical evaluation of athletes that have sustained an SRCC. Although it was found in this study that mouthguard use does not decrease the severity of concussion, it is important to note that the use of mouthguards is paramount in reducing maxillofacial and dental trauma and their use should continue to be mandated by athletic associations and supported by all dental and sports medicine professionals.     

Mouthguard utilization rates during sport activities in Ankara, Turkey

Abstract –  The objective of this study was to determine the attitudes towards mouthguard use in Ankara, Turkey. In the first part of this study, an eight-item questionnaire was distributed to 22 coaches from 15 secondary schools randomly selected from five municipalities of Ankara, Turkey. The questionnaire sought information on how much coaches know regarding mouthguards and how often children and adolescents of the ages 11–18 use mouthguards. The second part of the study was based on the data obtained from direct interviews answered by 121 university athletes of three different sport modalities (football, ice hockey and martial arts). The purpose of this part of the study was to determine the rate of mouthguard use and the frequency and type of oral trauma in these athletes. The result of the coaches' questionnaires revealed that; none of the 11–18 years old children and adolescents used mouthguards while participating in sports. Of the coaches, 77.2% had seen orofacial trauma in this age group during sport activities and 95.5% of the coaches believed that mouthguards prevented oral injuries. Of the coaches, 72.7% reported that children and adolescents should use mouthguards in sport activities. The second part of the study showed that although all of the athletes owned mouth-formed type of mouthguards, the utilization rate was 74.4%. Of all players, 13.2% had suffered from one or more form of oral injury while not wearing mouthguards. The results show that in Turkey, the use of mouthguards has not become widespread in sports. It can be concluded that regular mouthguard use in sports should be encouraged in Turkey.     

An evaluation of mouthguard programs in Texas high school football

Recent publications have indicated the interest in and controversy surrounding mouth protectors in sports dentistry. Mouth protection for athletes has been and continues to be dentistry's contribution to sports. Perhaps no other item of protective equipment is more effective in reducing injury to football players than a mouthguard. Although protection is no longer doubtful when a mouthguard is worn, there are still many mouthguards used that are not acceptable to the athletes in terms of comfort, durability, and speech. It is the responsibility of the dental profession to develop and dispense the best mouthguards available. From the present study it may be concluded that a properly constructed custom-made mouthguard will minimize the common complaints coaches and trainers have concerning mouthguards. It is apparent that more education about the types of mouthguards, their merits, and their availability is needed.     

Nigerian dentists' knowledge and attitudes towards mouthguard protection

Abstract –  The objective of this study was to assess the knowledge and attitudes of Nigerian dentists towards mouthguard protection. A pre-tested 15-item, one-page questionnaire was distributed to 185 dentists practising in different parts of the country with government hospitals or private establishments, by 'hand-delivery' system. Filled and returned forms were 170 (response rate of 92%). The period of the survey was between April and August 2003. Dental graduates from the different dental schools in the country responded to this survey. About 49% of the respondents indicated having only classroom lectures on mouthguards during their undergraduate trainings, 11% said they had some laboratory sessions in addition while no form of education on mouthguards was received by 40%. About 82% had never recommended mouthguard protection for athletic patients, and the major reason was no formal training in the subject. Only 58.5% were familiar with the different types of mouthguards, 75.9% would not be able to supervise or fabricate mouthguards and 50.6% would prefer custom-made mouthguard for their athletic patients. About 84% felt the current training on mouthguards in Nigerian dental schools is inadequate. Over 98% agreed that mouthguard usage in contact sports should be encouraged with the involvement of the dentists. The knowledge and attitudes of the respondents towards mouthguard protection did not vary significantly across years of postqualification from dental schools as well as the professional status of the dentists ( P  > 0.05). Although Nigerian dentists support mouthguard protection in contact sports and want to be involved in the provision of mouthguards for athletes, their knowledge of the protective device is inadequate. There is need for attention to be given to this subject in the undergraduate curricula of our dental schools.     

Laboratory evaluation of mouthguard material

Abstract – The aim of this study was to evaluate, in vitro , the EVA material (polyvinylacetate-polyethylene copolymer) most commonly used in the fabrication of mouthguards and thus to help understand mouthguard performance and to improve mouthguard design. The material was tested for tensile strength, elongation, hardness and water absorption using specimens and tests described by the American Society for Testing and Materials Standards. Standard EVA sheets of 1, 2, 3 and 5 mm thickness were prepared. With increase in the thickness of the material, both the ultimate tensile strength and the elongation were decreased. The hardness and water absorption were unaffected. It was concluded that, overall, the thicker 5 mm EVA material was recommended for mouthguards as it displayed the least deformation to load and performed equally as well in the tests as other thicknesses.     

Rugby players'' satisfaction with custom-fitted mouthguards made with different materials

OBJECTIVES: This study compared the comfort of two bimaxillary custom-fitted mouthguards. One type was made with silicone rubber and the other with methyl-methacrylate (acrylic). METHODS: The study was a within-subject crossover clinical trial with 52 high-school rugby players who were randomly allocated to one of two groups. The first group wore a silicone mouthguard for 4 months and an acrylic one for the following 4-month period. The second group wore an acrylic mouthguard followed by a silicone one for similar periods. Comfort, bulkiness, stability, hardness, ability to talk and to breathe, oral dryness, nausea and inclination to chew were evaluated for each period using a Visual Analogue Scale questionnaire. RESULTS: There was no significant difference concerning comfort, bulkiness, ability to talk and to breathe, oral dryness and nausea between silicone and acrylic mouthguards by group and time of examination (Three-way ANOVA P>0.05). Acrylic mouthguards were more stable and harder than silicone ones (Wilcoxon's test P<0.01). Tendency to chew was greater for silicone appliances (P<0.01). For stability, hardness and inclination to chew, there was no significant difference in the response of the players based on the sequence of use of the two types of mouthguard during the survey (Mann-Whitney test P>0.05). At the end of the study, 56% of the players preferred to keep the acrylic mouthguard and 44% chose the silicone one. This choice did not vary between the groups (chi2, P>0.05). CONCLUSION: Silicone rubber mouthguards were well accepted by the players but technical improvements in silicone materials are needed to improve hardness and stability of silicone mouthguards for sport.