Impressions Reinforced with Rigid Mouthguards

The impression materials utilized today in dental medicine offer a good reproducibility and are easily accepted by patients. However, because they are polymer-based, they have issues regarding their dimensional stability. In this respect, the present work proposes a new type of dental impression, which is reinforced with rigid mouthguards. The aim of the study is to test the performances of such new impressions by comparing them to conventional ones-from this critical point of view, of the dimensional stability. Three types of polymeric materials were considered for both types of impressions: alginate, condensation silicone, and addition silicone. In order to obtain the new type of impressions, a manufacturing technique was developed, comprising the following phases: (i) conventional impressions were made; (ii) a plaster model was duplicated, and 15 rigid mouthguards were obtained; (iii) they were inserted in the impression technique, with each mouthguard positioned on the cast before the high-consistency material was inserted in the tray and the practitioner took the impression; (iv) the mouthguard remained in the tray and the low-viscosity material was inserted over the mouthguard; (v) the impression was positioned on the model, and after the material hardened, the mouthguard-reinforced impression was analyzed. In the evaluation of the dimensional stability, rigorous statistical analysis was essential to discern the performance differences between conventional and mouthguard-reinforced dental impressions. Statistical analyses employed non-parametric Mann-Whitney U tests because of the non-normal distribution of the data. They indicated a statistically significant improvement in the dimensional stability of addition silicone impressions when reinforced with mouthguards (p < 0.05), showcasing superior performance over conventional methods. Conversely, alginate and condensation silicone reinforced impressions did not exhibit the same level of stability improvement, suggesting the need for further optimization of these materials. In conclusion, from the three considered elastomers, addition silicone was found to be the prime candidate for high-precision dental impressions, with the potential to improve their quality from conventional impressions by utilizing the proposed reinforcing technique.

The effect of the simulated aging by thermocycling on the elastic modulus of ethylene-vinyl acetate brands and stress/strain development during an impact: An in vitro and 3D-FEA analysis

BACKGROUND/AIM

Mouthguards are used to prevent dental trauma and orofacial injuries. The aim of this study was to evaluate the influence of ethylene-vinyl acetate (EVA) aging by thermocycling on elastic modulus, stress, strain and shock absorption ability of different ethylene-vinyl acetate brands used for mouthguards.

METHODS

Thirty EVA samples with a dimension of 70 × 10 × 3 mm were obtained from four commercial brands (Bioart®, Erkodent®, Polyshok® and Proform®). Fifteen samples were submitted to 10,000 cycles (5°C-55°C) in a thermocycling machine with an immersion time of 30 s and a transfer time of 5 s. The samples were submitted to a uniaxial tensile test in a universal testing machine to calculate the elastic modulus. Data were statistically evaluated by two-way ANOVA and Holm-Sidak test. A three-dimensional model of the anterior maxilla was created using Rhinoceros 5.0. A 3 mm custom-fitted mouthguard was simulated. The three-dimensional volumetric mesh was generated using the Patran software (MSC Software) with isoparametrics, 4-noded tetrahedral elements and exported to Marc/Mentat (MSC Software) as element number 134. A non-linear dynamic impact analysis was performed in which a rigid object struck the central incisor at a speed of 5 m/s. The stresses were evaluated by the modified von Mises criteria and the strains were also recorded.

RESULTS

Statistically significant differences were observed for elastic modulus values (p < .001). Mean and standard deviation values (MPa) without thermocycling were: Bioart (34.5 ± 0.9), Erkodent (15.0 ± 0.4), Polyshok (17.3 ± 0.4), Proform: (20.6 ± 0.8); and with thermocycling: Bioart (25.4 ± 0.8), Erkodent (10.7 ± 0.5), Polyshok (13.3 ± 0.6), Proform (13.1 ± 0.6). The thermocycling process reduced stress and strain levels regardless of the mouthguard materials. Shock absorption ability calculated based on the strain values was increased with thermocycling process.

CONCLUSION

The thermocycling process, regardless of the commercial brand, reduced the stress/strain and increased the shock absorption ability of mouthguards.

A Shear-Stiffening Mouthguard with Excellent Shock Absorption Capability and Remoldability via a Dynamic Dual Network

Mouthguards are used to reduce injuries and the probability of them to orofacial tissues when impacted during sports. However, the usage of a mouthguard is low due to the discomfort caused by the thickness of the mouthguard. Herein, we have constructed a dynamic dual network to fabricate a shear-stiffening mouthguard with remoldability, which are called remoldable shear-stiffening mouthguards (RSSMs). Based on diboron/oxygen dative bonds, RSSMs show a shear-stiffening effect and excellent shock absorption ability, which can absorb more than 90% of the energy of a blank. Even reducing the thickness to half, RSSMs can reduce approximately 25% of the transmitted force and elongate by about 1.6-fold the buffer time compared to commercial mouthguard materials (Erkoflex and Erkoloc-pro). What is more, owing to the dynamic dual network, RSSMs show good remolding performance with unchanged shear-stiffening behavior and impact resistance, which conforms to the existing vacuum thermoforming mode. In addition, RSSMs exhibit stability in artificial saliva and biocompatibility. In conclusion, this work will broaden the range of mouthguard materials and offer a platform to apply shear-stiffening materials to biomedical applications and soft safeguarding devices.

Mouthguard-Type Wearable Sensor for Monitoring Salivary Turbidity to Assess Oral Hygiene

Salivary turbidity is a promising indicator for evaluating oral hygiene. This study proposed a wearable mouthguard-type sensor for continuous and unconstrained measurement of salivary turbidity. The sensor evaluated turbidity by measuring the light transmittance of saliva with an LED and a phototransistor sealed inside a double-layered mouthguard. The sensor was also embedded with a Bluetooth wireless module, enabling the wireless measurement of turbidity. The mouthguard materials (polyethylene terephthalate-glycol and ethylene-vinyl acetate) and the wavelength of the LED (405 nm) were experimentally determined to achieve high sensitivity in salivary turbidity measurement. The turbidity quantification characteristic of the proposed sensor was evaluated using a turbidity standard solution, and the sensor was capable of turbidity quantification over a wide dynamic range of 1-4000 FTU (formazine turbidity unit), including reported salivary turbidity (400-800 FTU). In vitro turbidity measurement using a saliva sample showed 553 FTU, which is equivalent to the same sample measured with a spectrophotometer (576 FTU). Moreover, in vivo experiments also showed results equivalent to that measured with a spectrophotometer, and wireless measurement of salivary turbidity was realized using the mouthguard-type sensor. Based on these results, the proposed mouthguard-type sensor has promising potential for the unconstrained continuous evaluation of oral hygiene.

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 10: First aid education

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 4: Faceshields for the prevention of dental and oral trauma

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 6: Education

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 2: Primary prevention of dental trauma across the life course

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 3: Mouthguards for the prevention of dental and oral trauma

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 8: ToothSOS app

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 5: Secondary prevention of dental injuries

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

The International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD) guidelines for prevention of traumatic dental injuries: Part 1: General introduction

The Guidelines for Prevention of Traumatic Dental Injuries were reviewed and approved by the Board of Directors of the International Association of Dental Traumatology (IADT) and the Academy for Sports Dentistry (ASD).

Methods and applications of finite element analysis in dental trauma research: A scoping review

Finite Element Analysis (FEA) is vital for understanding dental traumatology (DT) biomechanics, aiding diagnosis, treatment planning, and outcome prediction. This review explores FEA applications in DT research, evaluates their quality and outcomes, and assesses methodological aspects. Accordingly, recommendations for future researchers are provided. The study adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for scoping reviews and registered in Open Science framework. A comprehensive search using relevant text-words and MeSH terms was performed in established databases. The inclusion criteria encompassed all Finite element analysis (FEA)-based Dental traumatology (DT) studies without language or publication year restrictions. Risk of bias was assessed with the Risk of bias tool for the use of finite element analysis in dentistry (ROBFEAD) tool. Forty-six studies published from 2001 to 2023 were included in the qualitative synthesis. The studies were categorized into five domains and six subdomains based on objectives. Maxillary central incisors and surrounding structures were commonly modelled (n = 27). Most studies utilized Computed tomography (CT), Cone Beam CT, or micro CT. Traumatic injury forces ranged from 100 N to 2000 N, and occlusal forces ranged from 150 N to 350 N. All studies were rated as high risk of bias. Fory-six studies were categorized, with most focusing on stress distribution and fracture patterns in dento-alveolar structures under various conditions, while few assessed displacements. Methodological quality lacked robustness in model development and substructure properties. Future studies should address these limitations and enhance reporting practices.

Comfort and wearability properties of custom-made and boil-and-bite mouthguards among basketball players: A randomized parallel arm clinical trial

BACKGROUND/AIM

Thermoplastic mouthguards have been a reliable means of protection against impacts and shocks for a century. Although orofacial injuries are prevalent among basketball players, many athletes still avoid using mouthguards due to concerns regarding impaired breathing, speech interference, and nausea. This study aims to compare basketball players' subjective assessments of two different thicknesses of custom-made mouthguards (MGs) with boil-and-bite MGs (B&B MG).

MATERIAL AND METHODS

A total of 60 systematically healthy male professional basketball players, without active orthodontic treatment, were enrolled and randomly assigned to three groups: Group 1 (received B&B MGs; n = 20), Group 2 (received custom-made MGs with a 3 mm thickness [ethyl vinyl asetat]; n = 20), and Group 3 (received custom-made MGs with a 5 mm thickness; n = 20). To evaluate MG comfort and usability, 12 key factors, including comfort, fit, stability, tiredness, thirsting, oral dryness, nausea, speaking, breathing, drinking, ease of wear and removal, and inclination to chew, were assessed. The athletes were made to rate these factors using a 10 cm-long Visual Analog Scale, measured at three-time intervals, and the values for both inter-group and intra-group were compared.

RESULTS

Data from 48 basketball players were retrieved, and data analysis revealed that B&B MGs had the least favorable parameter values. Among the B&B MG group, stability was reported to be poorer during the initial measurement (p < .05). In the second measurement, B&B MGs showed significantly lower values for comfort, stability, tiredness, speaking, and inclination to chew (p < .05). During the third measurement, the B&B MG group exhibited significantly reduced values for comfort, breathing, drinking, and speaking (p < .05). In contrast, no statistically significant difference was observed between 3 and 5 mm thickness MGs in these measurements.

CONCLUSIONS

Custom-made MGs with different thicknesses consistently outperformed B&B MGs in all measurements, indicating the potential to tailor MG thickness based on sport, age, professional level of athlete, and presence of other protective equipment. While custom-made mouthguards are considered the gold standard, dentists who provide B&B MGs can lead to cost savings while maintaining protection and encouraging athletes to use higher-quality custom-made mouthguards.

Fatal Complication of Mouthguard Used to Treat Awake Bruxism in Patient with Frontotemporal Dementia

Awake bruxism is an understudied manifestation of frontotemporal dementia, yet awake bruxism can have fatal consequences in the aging population. This report presents a patient suffering from awake bruxism associated with frontotemporal dementia being treated with a mouthguard, which ultimately becomes lodged in her posterior oropharynx leading to asphyxiation. The case highlights the need for investigation into the occurrence and treatment of awake bruxism among patients with dementia, and the unique risk-benefit analysis that must be performed to develop proper treatment plans for patients with dementia.

Knowledge of traumatic dental injuries and mouthguard behavior among Croatian soccer players

OBJECTIVES/AIM

Sports-related dental injuries occur frequently among athletes due to inadequate knowledge and prevention measures. The aim of the study was to assess knowledge, attitudes, and practices of active soccer players from all leagues in Croatia regarding traumatic dental injuries and the use of mouthguards.

MATERIAL AND METHODS

393 respondents completed a questionnaire-based online survey from March 2022 to April 2022. The questionnaire consisted of 37 questions divided in four sections: demographic characteristics, experience with orofacial injuries, knowledge of emergency therapeutic procedures for dental injuries, and behaviors related to the use of a mouthguard.

RESULTS

Insufficient knowledge was confirmed by a total score of 2.8 ± 2.8 points, with a possible maximum of 11. Respondents' better knowledge can be associated with educational level (p = .002), playing position (p = .046), and personally experienced injuries to the face and jaw (p ≤ .001) and teeth (p = .022). Less than 40% of respondents suffered facial and jaw injuries while playing football and 18.6% suffered dental injuries. Although most respondents (93.9%) were familiar with mouthguards and 68.9% believed that they help prevent injuries while playing football, only 16% used them.

CONCLUSION

The study revealed significant gaps in knowledge regarding dental injuries and the practice of mouthguard usage among Croatian soccer players. Therefore, it is evident that additional education is needed to prevent dental injuries and take proper procedures when taking care of them among the examined population.

Dental injuries in Swiss soccer supporters: A comparative study of regular fans, ultras, and hooligans for public health strategies

OBJECTIVES

Violence among soccer supporters continues to pose a significant public health concern in many parts of the world. In Switzerland, hooliganism is largely uninvestigated. This study aimed to examine incidents of violence and associated dental injuries among different groups of soccer supporters, as well as assess the impact of intoxicants on their behavior, using survey data from regular fans, ultras, and hooligans in the Swiss Football League.

MATERIAL AND METHODS

A cross-sectional survey using a standardized questionnaire was conducted among distinct factions of soccer supporters in the Swiss Football League in 2022. A total of 165 participants self-identified as belonging to one of three subgroups: "regular fan," "ultra," or "hooligan." Data were gathered on physical altercations, dental injuries, possession of mouthguards, intoxicant use, and medical assistance. Descriptive statistics, logistic regression models, and significance tests were used for data analysis (α = .05).

RESULTS

Hooligans had a higher frequency of dental injuries resulting from fights than ultras and regular fans. Hooligans with 11-20 fights per soccer season had a 9.6 times higher probability of dental trauma than those with 0-5 fights (p = .048). Possession of a mouthguard was associated with a lower risk of dental injuries for hooligans but an increased risk for ultras. Additionally, hooligans were found to differ significantly from other groups in their consumption of amphetamines and cocaine (p < .001).

CONCLUSIONS

The study found a strong link between physical altercations and dental injuries among soccer supporters. To promote better prevention, there is a necessity for enhanced educational initiatives facilitated by dentists to amplify the dissemination of mouthguards. Furthermore, it is crucial to raise awareness regarding their proper fitting to minimize the occurrence of combat-related dental injuries. Health authorities and other stakeholders should take a comprehensive approach to addressing some of the root causes of violent behavior, which include alcohol abuse and illicit substance consumption.

Effect of different materials for conventional and 3D-printed models on the mechanical properties of ethylene-vinyl acetate utilized for fabricating custom-fit mouthguards

BACKGROUND/AIM

The interaction between the ethylene-vinyl acetate (EVA) with distinct materials utilized for obtaining dental models can affect the performance of resulting mouthguards. This study attempted to evaluate the effect of different materials for conventional (dental stone) or 3D-printed (resin) models on EVA's physical and mechanical properties and surface characteristics.

MATERIAL AND METHODS

EVA sheets (Bioart) were laminated over four model types: GIV, conventional Type IV dental stone model (Zhermak); ReG, resin-reinforced Type IV dental stone model (Zero Stone); 3DnT, 3D resin printed model (Anycubic) without surface treatment; 3DT, 3D-printed model (Anycubic) with water-soluble gel (KY Jelly Lubricant, Johnson & Johnson) coating during post-curing process. The EVA specimens were cut following the ISO 37-II standard (n = 30). Shore A hardness was measured before and after plasticization on the contact (internal) or opposite (external) surfaces with the model. The breaking force (F, N), elongation (EL, mm), and ultimate tensile strength (UTS, MPa) were measured using a universal testing machine. Macro-photography and scanning electron microscopy were adopted for classifying the EVA surface alteration. Data were analyzed by one-way ANOVA with repeated measures, followed by Tukey's test (α = .05).

RESULTS

Plasticization significantly decreased Shore A values for the tested EVA regardless of the model type (p < .001). Higher F, El, and UTS values were verified for the EVA with 3DT and GIV models compared to ReG and 3DnT (p < .001). 3DnT models resulted in severe surface alteration and a greater reduction of the mechanical properties of the EVA.

CONCLUSION

The interaction of EVA with 3D resin-printed models without surface treatment or resin-reinforced Type IV dental stone models significantly affected the physical and mechanical properties of this material. The utilization of water-soluble gel coating during the post-curing process of 3D resin printed models improved the mechanical properties of the EVA, similarly when this material was plasticized over conventional Type IV dental stone model.

Mouthguards Based on the Shear-Stiffening Effect: Excellent Shock Absorption Ability with Softness Perception

Mouthguards are used to prevent craniomaxillofacial injuries when collisions happen during contact and high-speed sports. However, poor compliance with mouthguard wear in athletes is attributed to discomfort because of its thickness and hardness. These drawbacks significantly restrict their protective performance for oral tissues and applications during contact sports; as a result, the incidence of craniomaxillofacial injuries increases. In this study, non-Newton material is introduced into mouthguard material and then a mouthguard with shear-stiffening behavior is fabricated, which is named the shear-stiffening mouthguard (SSM). Compared with commercial mouthguard materials (Erkoflex and Erkoloc-pro), SSMs show remarkable enhancement of shock absorption ability with an approximately 60% reduction in peak force relative to commercial materials and approximately 3-fold extensive buffer time. Moreover, Young's modulus of SSMs (average 0.48 MPa) is extremely lower compared to commercial materials (22.88 MPa for Erkoflex and 26.71 MPa for Erkoloc-pro). This manifests that SSMs have not only excellent shock absorption ability but also softness perception. Moreover, SSMs show biocompatibility in vitro. In conclusion, this work provides a platform to develop a new type of thin and soft mouthguard with a shear-stiffening effect and broadens the horizon in protecting oral tissues with shear-stiffening materials.

Validation of an instrumented mouthguard in rugby union-a pilot study comparing impact sensor technology to video analysis

Background

To better understand the biomechanical profile of direct head impacts and the game scenarios in which they occur in Rugby Union, there is a need for an on-field validation of a new instrumented mouthguard (IMG) against the reference standard. This study considers the potential of a combined biomechanical (IMG) and video analysis approach to direct head impact recognition, both of which in isolation have limitations. The aim of this study is to assess the relationship between an instrumented mouthguard and video analysis in detection of direct head impacts in rugby union.

Design

Pilot Study - Observational Cohort design.

Methods

The instrumented mouthguard was worn by ten (3 backs, 7 forwards) professional Rugby Union players during the 2020-21 Gallagher Premiership (UK) season. Game-day video was synchronized with timestamped head acceleration events captured from the instrumented mouthguard. Direct Head Impacts were recorded in a 2 × 2 contingency table to determine sensitivity. Impact characteristics were also collected for all verified head impacts to further the understanding of head biomechanics during the game.

Results

There were 2018 contact events that were reviewed using video analysis. Of those 655 were categorized as direct head impacts which also correlated with a head acceleration event captured by the IMG. Sensitivity analysis showed an overall sensitivity of 93.6% and a positive predictive value (PPV of 92.4%). When false positives were excluded due to ball out of play, mouthguard removal or handling after a scoring situation or stoppage, PPV was improved (98.3%). Most verified head impacts occurred in and around the ruck contest (31.2%) followed by impacts to the primary tackler (28.4%).

Conclusion

This pilot validation study demonstrates that this IMG provides a highly accurate measurement device that could be used to complement video verification in the recognition of on-field direct head impacts. The frequency and magnitude of direct head impacts derived from specific game scenarios has been described and allows for greater recognition of high-risk situations. Further studies with larger sample sizes and in different populations of Rugby Union players are required to develop our understanding of head impact and enable strategies for injury mitigation.

Knowledge and Self-Assessment of Dental Injuries and Oral Health among Croatian Professional Water Polo Players: A Cross-Sectional Study

OBJECTIVES/AIM

The purpose of this study was to evaluate oral health knowledge, and the incidence of self-reported dental injuries incidence, the frequency of mouthguard use, oral hygiene habits, and oral health status among professional water polo players.

MATERIALS AND METHODS

During the 2022/2023 season, 114 water polo players from the Croatian First League participated in a questionnaire-based online survey. The data collected included sociodemographic and professional attributes, oral health knowledge questions, dental injury experiences, and practices related to mouthguard use. Respondents also rated their own oral health status and oral hygiene habits. The data were analyzed using descriptive statistics and a regression analysis.

RESULTS

The respondents demonstrated inadequate knowledge of oral health, with a mean score of 6.4 ± 2.6 out of 12. Better knowledge correlated positively with older age (p ˂ 0.05) and consistent flossing (p = 0.014). Additionally, 27.2% (31 of 114) of reported dental injuries were related directly to incidents which occurred while participating in water polo. These injuries occurred more frequently during games (54.8%) and often involved the anterior maxillary incisors (71.0%) due to player contact (87.1%). Awareness of mouthguards was high (93.9%), whereas their actual use was low (7.0%) because 35.1% of respondents reported discomfort wearing them. The respondents' self-assessments revealed widespread dental problems, including tooth sensitivity (13.3%), erosion (15.8%), calculus (28.1%), and pigmentation (7.9%).

CONCLUSIONS

The research results indicate a lack of adequate knowledge among the respondents regarding oral health. This deficit was not associated with oral hygiene habits or oral cavity conditions. These findings highlight the disparities in oral health awareness and practices associated with water polo participation and emphasize the importance of education and prevention efforts.

An Instrumented Mouthguard for Real-Time Measurement of Head Kinematics under a Large Range of Sport Specific Accelerations

BACKGROUND

Head impacts in sports can produce brain injuries. The accurate quantification of head kinematics through instrumented mouthguards (iMG) can help identify underlying brain motion during injurious impacts. The aim of the current study is to assess the validity of an iMG across a large range of linear and rotational accelerations to allow for on-field head impact monitoring.

METHODS

Drop tests of an instrumented helmeted anthropometric testing device (ATD) were performed across a range of impact magnitudes and locations, with iMG measures collected concurrently. ATD and iMG kinematics were also fed forward to high-fidelity brain models to predict maximal principal strain.

RESULTS

The impacts produced a wide range of head kinematics (16-171 g, 1330-10,164 rad/s2 and 11.3-41.5 rad/s) and durations (6-18 ms), representing impacts in rugby and boxing. Comparison of the peak values across ATD and iMG indicated high levels of agreement, with a total concordance correlation coefficient of 0.97 for peak impact kinematics and 0.97 for predicted brain strain. We also found good agreement between iMG and ATD measured time-series kinematic data, with the highest normalized root mean squared error for rotational velocity (5.47 ± 2.61%) and the lowest for rotational acceleration (1.24 ± 0.86%). Our results confirm that the iMG can reliably measure laboratory-based head kinematics under a large range of accelerations and is suitable for future on-field validity assessments.

Effects of Mouthguards on Skin Damage In Vitro Study

OBJECTIVE

 Mouthguards can prevent and reduce orofacial sports traumas, which occur to the players themselves. However, the effect of mouthguards on skin damage has not been clarified. The present study's purpose was to examine whether the mouthguard can reduce or prevent skin damage caused by teeth (including the difference in mouthguard thickness).

MATERIALS AND METHODS

 Pigskins, artificial teeth, and Ethylene-vinyl acetate (EVA) mouthguard blanks with 1.5- and 3.0-mm thickness were employed. Each of the two type mouthguards was produced in 10 replicates. Mouthguard incisal thickness and collision touch angle were measured on a PC using imaging software. A pendulum-type machine was used to apply impact. Strain gauges attached to the tooth and impacted plate were used to measure mouthguards' effect on impact stress. Also, a microscope was used to observe the after impacted skin condition, and the extent of damage was assessed as a score.

RESULTS

 The pigskin was ruptured in without mouthguard (NOMG) with presenting the highest damage score, whereas the complete rupture was not seen in the 1.5 mm MG, but the damage of the skin (defeat) was observed. No tissue change was found with the 3 mmMG. In both the flat plate and impact tooth strain, no significant difference was observed between NOMG and 1.5 mmMG. However, 3 mmMG had a significantly smaller value than the other two conditions. These results are likely to be strongly influenced by the mouthguard incisal thicknesses and collision touch angles differences.

CONCLUSION

 The present study results clarified that two different thickness mouthguards reduced the skin damage, and the thicker mouthguard showed more effectiveness. Therefore, mouthguards may prevent the wearer's stomatognathic system's trauma and avoid damage to the skin of other athletes they are playing with. This effect seems to be an essential basis for explaining the necessity of using mouthguards for others besides full-contact sports.

Real-Time Continuous Monitoring of Oral Soft Tissue Pressure with a Wireless Mouthguard Device for Assessing Tongue Thrusting Habits

In orthodontics, understanding the pressure of oral soft tissues on teeth is important to elucidate the cause and establish treatment methods. We developed a small wireless mouthguard (MG)-type device that continuously and unrestrainedly measures pressure, which had previously been unachieved, and evaluated its feasibility in human subjects. First, the optimal device components were considered. Next, the devices were compared with wired-type systems. Subsequently, the devices were fabricated for human testing to measure tongue pressure during swallowing. The highest sensitivity (51-510 g/cm²) with minimum error (CV < 5%) was obtained using an MG device with polyethylene terephthalate glycol and ethylene vinyl acetate for the lower and upper layers, respectively, and with a 4 mm PMMA plate. A high correlation coefficient (0.969) was observed between the wired and wireless devices. In the measurements of tongue pressure on teeth during swallowing, 132.14 ± 21.37 g/cm² for normal and 201.17 ± 38.12 g/cm² for simulated tongue thrust were found to be significantly different using a t-test (n = 50, p = 6.2 × 10^-19), which is consistent with the results of a previous study. This device can contribute to assessing tongue thrusting habits. In the future, this device is expected to measure changes in the pressure exerted on teeth during daily life.

Biomechanical effects of a hard insert and air space in mouthguards on the shock absorption and protection against fractures of direct resin composite veneers from trauma

BACKGROUND/AIM

Mouthguards (MTG) are used to prevent dental trauma. However, their protective effect on esthetic restorations and whether modified MTGs are beneficial are uncertain. The aim of this study was to evaluate the effect of hard inserts and air spaces in MTGs in protecting direct resin composite veneers during impact.

MATERIALS AND METHODS

Twenty resin composite veneers (1.0 mm) were prepared on upper right central incisors on printed maxilla models using polyether. The effect of the MTGs was evaluated in four groups (n = 5): Con-MTG, conventional custom-fit MTGs made with two layers of ethylene vinyl acetate (EVA); Air-MTG, MTGs with the insertion of 2.0 mm air space between the two layers of EVA and tooth surface; PETG-MTG, MTGs with 1.0 mm of polyethylene terephthalate glycol-modified (PETG) inserted between the EVA layers; and No-MTG, comprising resin composite veneers without MTG. The printed models were fixed in a pendulum device, and the impact was performed at 30°. The strain (μS) and shock absorption (%) of the MTG were recorded using strain gauges. Failure modes and cracks were evaluated using macro photography and transillumination and analyzed using the Chi-square test. Strain and shock absorption data were analyzed using the one-way Analysis of Variance followed by Tukey's test (α = 0.05).

RESULTS

MTGs reduced strain and enhanced shock absorption, regardless of the MTG type (p < 0.001). Con-MTG, Air-MTG, and PETG-MTG had shock absorption rates of 76.1%, 72.3%, and 33.4%, respectively (p < 0.001). The single No-MTG model had a root fracture, while all the others had superficial damage. None of the MTG models had cracks or fractures.

CONCLUSIONS

MTGs protected the resin composite veneers. The Con-MTG and Air-MTG groups had lower strain and greater shock absorption than the PETG-MTG. Resin veneers had no cracks or damage following MTG use. However, 80% of the veneers had surface damage when no MTG was used.

Effect of surface treatment of ethylene vinyl acetate on the delamination of custom-fitted mouthguards

BACKGROUND/AIM

Contamination of ethylene vinyl acetate (EVA) during mouthguard fabrication can cause delamination. The study evaluated the effects of different EVA surface treatments on the contact angle, laminate bond strength, and elongation capacity.

MATERIALS AND METHODS

Specimens of two bonded EVA plates were prepared (n = 30). The Shore A hardness of standardized EVA plate specimens was measured before and after thermo-plasticization. The EVA plates were randomly allocated to one of five different surface treatment groups: no treatment (control); isopropyl alcohol, 100%; chloroform, 99.8%; self-cure acrylic resin monomer (methacrylate, ethylene glycol dimethacrylate, and chemical initiator-amine type); and ethyl alcohol, 70%. The maximum breaking force and elongation at the site of fracture were recorded using a universal testing machine. The contact angle surface was measured using ImageJ software. Scanning electron microscopy of the EVA surface was performed. The laminate bond strength was obtained by dividing the maximum breaking force by the bonding area between the two EVA plates. The laminate bond strength and maximum elongation data were analyzed by one-way ANOVA, followed by the Tukey's and the Dunnet test. The failure mode data was analyzed using the chi-square test (α = .05).

RESULTS

EVA surface treatment significantly influenced the laminate bond strength and maximum elongation (p < .001). The control group had a higher contact angle and significantly lower laminate bond strength and maximum elongation than the other groups (p < .001). The acrylic resin monomer and chloroform-treated specimens had similar laminate bond strength and maximum elongation. The acrylic resin monomer group had a significantly lower contact angle (p < .001).

CONCLUSIONS

All treatments had a significantly higher laminate bond strength and maximum elongation than the control group. The acrylic resin monomer and chloroform groups had a significantly higher laminate bond strength and maximum elongation and the acrylic resin monomer group had a lower contact angle than the other groups. The chloroform should be avoided due its hazardous effects.

Self-reported injuries to oral tissues through resistance training in bodybuilders

Lifting heavy weights almost automatically elicits teeth clenching, which, if performed regularly, may lead to chronic trauma. This study assessed self-reported injuries to oral tissues in athletes and bodybuilders caused by resistance training and determined the association between self-reported trauma, performance level and the duration of practicing resistance training. A standardized questionnaire was used to gather information about the respondents (age and gender), their performance level (hobby versus competition athlete), experience with oral tissue trauma, the use of mouthguards, and dietary habits. From a total of 363 females and 239 males, 221 (36.7%) classified themselves as competition athletes and 381 (63.3%) as hobby athletes. Nearly 34.6% (n = 202) of the participants declared distress in their orofacial region during practice. Female hobby athletes reported 2.5 times more mouth-teeth-jaw problems than female competition athletes (p < 0.001). Females showed themselves slightly more susceptible to mouth-teeth-jaw problems with resistance training than males (odds ratio [OR] = 1.45, p = 0.076). Negative oral effects were found to be 2.1 (p = 0.003) times higher for those who had been practicing for 10 years or more. It was concluded that a higher number of years of resistance training increased self-reported oral tissue trauma in the current cohort. Females were more likely to report orofacial problems than males.

Prioritizing model trimming to prevent thinning during mouthguard thermoforming: Influence of increased height associated with an acute model angle

BACKGROUND/AIM

The shape of the working model is one of the major factors affecting the thickness of thermoformed mouthguards. The aim of this study was to clarify the priority of model trimming to prevent thinning during mouthguard thermoforming.

MATERIALS AND METHODS

Mouthguards were thermoformed using 4.0 mm thick ethylene-vinyl-acetate sheets and a vacuum forming machine. Working models were trimmed so that the angles of the labial surface to the model base were 100°, 90°, and 80°. The posterior height was unified to 30 mm, and the anterior heights were 30 mm (A100-L), 35 mm (A90-M), and 40 mm (A80-H), respectively. When the sheet temperature reached 100°C, vacuum forming was performed. Six specimens were formed for each condition. Mouthguard thickness (incisal edge, labial surface, cusp, and buccal surface) was measured using a specialized caliper accurate to 0.1 mm. Differences in thickness reduction rate due to model shapes were analyzed by one-way ANOVA and Bonferroni's multiple comparison tests.

RESULTS

At the incisal edge, there were no significant differences in the reduction rate of the thickness of the mouthguard according to model shapes. On the labial surface, cusp, and buccal surface, the smaller the model angle, the smaller the reduction rate of thickness, and significant differences were observed between A100-L and A80-H, and A90-M and A80-H. On the labial and buccal surfaces, A80-H was more than 7.1% thicker compared with A100-L and more than 5.6% thicker compared with A90-M, and the thickness reduction rate was reduced when the model was trimmed to an acute angle. At the cusp, A80-H was more than 4.3% thicker than A100-L and A90-M.

CONCLUSIONS

It is useful to trim the model at an acute angle in order to prevent thinning during mouthguard thermoforming, even if the anterior height of the model is increased.

In vitro study of how the undercut amount on the model labial side affects the reduction rate of laminated mouthguard thickness

BACKGROUND/AIM

An undercut on the model's labial side affects the mouthguard thickness. The aim of this study was to investigate how the undercut amount on the model's labial side affects the reduction rate of laminated mouthguard thickness.

MATERIALS AND METHODS

Mouthguards were thermoformed using 3.0-mm-thick ethylene-vinyl-acetate sheets for the first and second laminates and a pressure molding machine. Working models were three hard plaster models trimmed so that the undercut amount on the model's labial side was 0°, 10°, and 20° (U0, U10, and U20). A specialized caliper was used to measure the thickness of the incisal, labial surface, and buccal surface of the first layer and the laminated mouthguards. Thickness reduction rate of the first layer or laminated mouthguard due to the model undercut amount were analyzed using one-way ANOVA. Additionally, in each model, the difference in the thickness reduction rate between the first layer and the laminated mouthguard were analyzed by Student's t-test or Welch's test.

RESULTS

Differences in the thickness reduction rate depending on the model's undercut amount showed the same tendency between the first layer and the laminated mouthguard. Significant differences were observed between U0 and U10 as well as U0 and U20 at the incisal edge, and these were observed among all models on the labial and buccal surfaces (p < .01). On the labial surface, the rate of decrease in the laminated mouthguard thickness compared to U0 was approximately 10.4% larger for U10 and approximately 14.9% larger for U20 (p < .01). The thickness reduction rate of the laminated mouthguard was significantly smaller than that of the first layer, which was observed in all models at the incisal edge and in U10 and U20 on the labial surface (p < .01).

CONCLUSIONS

The presence of a 10° or 20° undercut on the model's labial side increases the thickness reduction rate on the labial side of the laminated mouthguard by approximately 10% or 15%.

Effect of sheet extrusion direction on laminated mouthguard thickness: An in vitro study

BACKGROUND/AIM

The thermal shrinkage that occurs when the extrusion molding sheet is heated affects the mouthguard thickness. The aim of this study was to investigate the effect of sheet extrusion direction on laminated mouthguard thickness.

MATERIALS AND METHODS

Mouthguards were pressure formed using the extruded sheet and a plaster model. For the first layer, a 3.0-mm-thick sheet was used. For the second layer, a 2.0- or 3.0-mm-thick sheet was used. In each of the first (F) and second (S) layers, the sheet extrusion direction was either vertical (V; FV, SV) or parallel (P; FP, SP) to the model midline. Thickness differences depending on the extrusion direction of the first layer was analyzed by Student's t-test. Differences in the laminated mouthguard thickness depending on the extrusion direction of the first or second layer and the sheet thickness of the second layer were analyzed by three-way ANOVA.

RESULTS

The first layer was significantly thicker in FV by about 0.20 mm than in FP at the incisal edge, labial surface, and cusp (p < .01). No significant difference was observed between SV and SP in the laminated mouthguard. However, at the incisal edge, labial surface, and cusp of the laminated mouthguard, FV were significantly thicker by 0.17 mm or more than FP under all laminating conditions (p < .01). A 3.0-mm-thick laminating condition was thicker than a 2.0-mm-thick laminating condition by 0.47 mm or more at the incisal edge, labial, and buccal surfaces, and by 0.34 mm or more at the cusp.

CONCLUSIONS

The laminated mouthguard thickness can be secured by molding the first-layer sheet so that the extrusion direction is vertical to the model midline. In the second layer, the extrusion direction did not affect the laminated mouthguard thickness, and a thicker sheet material should be used.

Effective thermoforming method for maintaining mouthguard thickness with a circular sheet using a circular frame

BACKGROUND/AIM

Mouthguard thickness is important to prevent oral and facial trauma during sports. The aim of this study was to establish an effective thermoforming method for maintaining mouthguard thickness with a circular sheet using a circular frame.

MATERIALS AND METHODS

Mouthguards were thermoformed using 4.0-mm-thick ethylene vinyl acetate sheets and a vacuum forming machine. Each sheet was pinched at the top and bottom and stabilized by a circular frame. Two heating conditions were compared: (1) condition N, where the sheet was formed when it sagged 10 mm below the level of the sheet frame at the top of the post, and (2) condition L, where the sheet frame was lowered 50 mm below the ordinary level and heated, and the sheet was formed when it sagged 10 mm. In each heating method, two forming conditions were compared: (1) when the sheet softened, the sheet frame was lowered and formed (condition C; N-C, L-C), and (2) after the sheet frame was lowered, the model was moved forward 20 mm and then formed (condition MP; N-MP, L-MP). Six mouthguards were fabricated for each condition. Thickness differences due to heating conditions and forming conditions were analyzed by the two-way ANOVA and Bonferroni's multiple comparison test.

RESULTS

At the incisal edge and at the labial and buccal surfaces, significant differences were observed among all conditions, and the thicknesses were in the order N-C < L-C < N-MP <L-MP. At the cusp, significant differences were not observed depending on the heating conditions.

CONCLUSIONS

The thermoforming method with a circular sheet using a circular frame did not maintain a sufficient thickness only by the method of moving the model position just before formation. However, the results suggest that a single-layer mouthguard with a labial thickness of 3 mm or more could be fabricated by applying the method of lowering the sheet frame and heating the sheet.

Examination of thermoforming techniques to secure mouthguard thickness of the labial and buccal sides with a single sheet: An in vitro study

BACKGROUND/AIM

Mouthguards must have an appropriate thickness to prevent oral trauma during sports. The aim of this study was to establish a thermoforming technique to secure the labial and buccal thicknesses of the mouthguard with a single sheet.

MATERIALS AND METHODS

Mouthguards were thermoformed using 4.0-mm thick sheets manufactured by extrusion molding, a plaster model, and a vacuum forming machine. Two sheet installation conditions were compared: the sheet extrusion direction was either parallel (P) or vertical (V) to the model's centerline. In each extrusion direction, two forming conditions were compared: (1) the sheet was formed when it sagged 15-mm below the sheet frame at the top of the post (control group; C-P, C-V); and (2) the sheet frame was lowered 50-mm below the ordinary level and heated, the frame was lowered when it sagged 15-mm, and the model was moved forward 20-mm before formation (experimental group; E-P, E-V). Difference in thickness (incisal edge, labial surface, cusp, and buccal surface) due to sheet extrusion direction and forming conditions were analyzed by two-way ANOVA and the Bonferroni method.

RESULTS

At all measurement sites, a significant difference in thickness depending on the sheet extrusion direction was observed in the experimental group (p < .01), but not in the control group. Difference in thickness depending on the forming condition was observed at all measurement sites, and the thickness was in the order C-P, C-V < E-P < E-V. Thicknesses of E-P and E-V were 3.01 ± 0.03 mm and 3.25 ± 0.02 mm on the labial surface, and 2.81 ± 0.02 mm and 3.02 ± 0.02 mm on the buccal surface.

CONCLUSIONS

It was possible to obtain 3 mm or more thickness on the labial and buccal sides with a single sheet by adjusting the sheet extrusion direction and the heating method of the sheet, and by applying the thermoforming method where the model is moved forward just before formation.

Utilization of mouthguards among school children in Saudi Arabia

AIM

To evaluate attitude towards mouthguard utilization among school children.

METHODS

This cross-sectional study was conducted among students of both genders, aged between 8 to 16 years, attending school in Riyadh, Saudi Arabia. A structural questionnaire was prepared consisting of questions related to the demographic details, attitude, and conception of children towards using a mouthguard. The questionnaire was sent to the school teachers to distribute among the respective school children. Descriptive statistics were used to analyze the data.

RESULTS

A total of 1116 children completed the survey form, of which 488 were female and 628 male. The prevalence of use of mouthguard among Saudi school children was found to be 3.32%. Out of the total study subjects, 72.68% of the subjects believed that mouthguards could protect them from injuries. The most common reasons for not wearing mouthguards were: they never thought about it (38.47), they felt it was not necessary (30.58%), it was expensive (11.02%), and they never had any injury (19.93%). Out of 37, 2 subjects never experienced any problem with mouthguards. The most common problems with the mouthguards were: difficulty in speech, being uncomfortable and expensive, followed by interference with breathing.

CONCLUSION

The prevalence of mouthguard use was 3.32% in Saudi school children aged between 8-16 years. The most common reason for not using it was found to be lack of knowledge. Counseling the young children interested in sports activities is the need of the hour.

Biomechanical Behavior Evaluation of a Novel Hybrid Occlusal Splint-Mouthguard for Contact Sports: 3D-FEA

Background: Orofacial injuries are common occurrences during contact sports activities. However, there is an absence of data regarding the performance of hybrid occlusal splint mouthguards (HMG), especially during compressive loading. This study amid to evaluate the biomechanical effects of wearing a conventional custom mouthguard (MG) or the HMG on the teeth, bone, and the device itself. Methods: To evaluate the total deformation and stress concentration, a skull model was selected and duplicated to receive two different designs of mouthguard device: one model received a MG with 4-mm thickness and the other received a novel HMG with the same thickness. Both models were subdivided into finite elements. The frictionless contacts were used, and a nonlinear analysis was performed simulating the compressive loading in occlusion. Results: The results were presented in von-Mises stress maps (MPa) and total deformation (mm). A higher stress concentration in teeth was observed for the model with the conventional MG, while the HMG design displayed a promising mechanical response with lower stress magnitude. The HMG design displayed a higher magnitude of stress on its occlusal portion (7.05 MPa) than the MG design (6.19 MPa). Conclusion: The hybrid mouthguard (HMG) reduced (1) jaw displacement during chewing and (2) the generated stresses in maxillary and mandibular teeth.

Dental and general injuries among ski and snowboard instructors in Switzerland, Germany, and Austria-A questionnaire-based study

Objectives

Data on the injury rate of skiers and snowboarders are currently limited. The aim of this study was, therefore, to assess the frequency of general and dental injuries among snow sports instructors, to investigate the use of protective gear and mouthguards, and to evaluate snow sports instructors' dental first aid know‐how.

Material and Methods

A questionnaire‐based, cross‐sectional study comprising 603 ski and snowboard instructors from Austria, Germany, and Switzerland was conducted in the timeframe December 2019 to May 2020. The survey gathered data on general and dental injuries sustained by instructors, protective gear usage, and know‐how in dental first aid. The statistical analysis included χ² tests, Wilcoxon rank‐sum and Kruskal–Wallis tests, and linear regression analysis. The level of significance was set at α = .05.

Results

Out of the 603 instructors, 326 (54.1%) sustained an injury while skiing or snowboarding. Forty (6.6%) reported a snow sports‐related dental injury. The rates of injuries related to skiing and snowboarding showed no significant difference (p = .0952). Compared with snowboarding on slopes, backcountry snowboarding entailed fewer risks of injury for snowboard instructors (p = .012). Knowledge of dental first aid was limited, with 45.8% of instructors uninformed about the possibility of replanting avulsed teeth. 10.1% of instructors were familiar with tooth rescue boxes. None of the instructors surveyed had a tooth rescue box in their first aid equipment. Helmet usage was high (95.6%) among snow sports instructors, whereas mouthguard usage was rare (3.5%).

Conclusions

Protective gear usage among snow sports instructors is high. The risk of dental injury while skiing or snowboarding is lower compared with other sports. Dental first aid know‐how ought to be enhanced in snow sports communities to ensure that appropriate first aid is provided in case of a dental injury related to skiing or snowboarding.

Appropriate fabrication method for pressure-formed mouthguards using polyolefin sheets

BACKGROUND/AIM

Polyolefin sheet mouthguards are usually formed in the same manner as ethylene-vinyl acetate sheet mouthguards. However, the heating condition of the polyolefin sheet for the pressure-forming process has not been determined. The aim of this study was to examine the appropriate heating condition for polyolefin sheet mouthguards when fabricated with the pressure-formed technique.

MATERIALS AND METHODS

Mouthguard sheets of 3.0 mm polyolefin were pressure formed on working models at three heating temperatures: 90°C, 105°C, and 120°C. The thickness of the mouthguard was measured at the labial surface of the central incisor, and the buccal and occlusal surfaces of the first molar. The fit of the mouthguard was examined at the central incisor and the first molar by measuring the distance between the mouthguard and the cervical margin of the working model. Differences in the thickness and fit of the mouthguards according to the heating conditions and the measured regions were analyzed using two-way analysis of variance.

RESULTS

Mouthguard thickness varied among the measured regions of the central incisors and first molars (p < .01). The greatest thickness was found at the labial surface of the central incisor in mouthguards fabricated with the heating temperature of 90°C (p < .01). The greatest thickness was found in mouthguards fabricated with the heating temperature of 105°C at the buccal surface of the first molar (p < .01), and 105°C or 120°C at the occlusal surface of the first molar (p < .01). The fit was not significantly different among the three heating conditions both at the central incisor and the first molar.

CONCLUSIONS

The appropriate heating condition for pressure-formed mouthguards using polyolefin sheets was 90°C to maintain the mouthguard thickness at the anterior teeth area with proper fit.

Modeling the Contact Interaction of a Pair of Antagonist Teeth through Individual Protective Mouthguards of Different Geometric Configuration

This study carried out modeling of the contact between a pair of antagonist teeth with/without individual mouthguards with different geometric configurations. Comparisons of the stress–strain state of teeth interacting through a multilayer mouthguard EVA and multilayer mouthguards with an A-silicon interlayer were performed. The influence of the intermediate layer geometry of A-silicone in a multilayer mouthguard with an A-silicon interlayer on the stress–strain state of the human dentition was considered. The teeth geometry was obtained by computed tomography data and patient dental impressions. The contact 2D problem had a constant thickness, frictional contact deformation, and large deformations in the mouthguard. The strain–stress analysis of the biomechanical model was performed by elastoplastic stress–strain theory. Four geometric configurations of the mouthguard were considered within a wide range of functional loads varied from 50 to 300 N. The stress–strain distributions in a teeth pair during contact interaction at different levels of the physiological loads were obtained. The dependences of the maximum level of stress intensity and the plastic deformation intensity were established, and the contact parameters near the occlusion zone were considered. It was found that when using a multilayer mouthguard with an A-silicone interlayer, there is a significant decrease in the stress intensity level in the hard tissues of the teeth, more than eight and four times for the teeth of the upper and lower teeth, respectively.

Cross-sectional cohort study on the use of mouthguards by children playing Gaelic football in Ireland

BACKGROUND/AIMS

Up to 40% of dental injuries in children occur during sports and may be prevented by using mouthguards (MG). The use of mouthguards is mandatory in some sporting organizations. Knowledge of the benefits of protection does not always result in mouthguard use. The aim of this observational cross-sectional cohort study was to measure and compare knowledge of 9-16-year-old Gaelic football players and their parents on MG use and compliance with MG rules.

MATERIALS AND METHODS

A convenience sample of players and their parents was identified and were assessed at their sports facility. Parents completed a questionnaire while children were asked standardized questions and MG type was verified by a dentist. Data were analysed using descriptive statistics and binary logistic regression analysis for comparison.

RESULTS

One hundred and twenty-one children with 118 parents participated in the study. According to players, MG use during competition (N = 119, 99.2%) was greater than during training (N = 97, 80.8%). As age increased, children were less likely to comply with MG rules during training (OR =0.18, p < .001). Children played a median of 2 contact sports (IQR = 1). Only 32 parents (27.1%) and 17 children (14%) reported that the child wore a MG for all sports. Only four children (3.8%) had a custom MG even though most parents (N = 87, 73.7%) believed that they provided superior protection. Knowledge of players and their parents on how to care for the MG was variable.

CONCLUSION

Compliance with the Gaelic Atheletic Association's MG rules was lower during training than competition. Children were less likely to comply with MG rules during training as they grew older. Most parents believed a custom MG would best protect their child's teeth, yet few children had a custom MG. Players and parents had variable knowledge in relation to MG hygiene.

Effects on the thickness of single-layer mouthguards with different model positions on the forming table and different sheet frame shapes for the forming device

BACKGROUND/AIM

Effectiveness and safety of mouthguards are greatly affected by their thickness. The aim of this study was to clarify the influence of the frame shape of the forming device on how the model position on the forming table affects the anterior and posterior mouthguard thickness.

MATERIALS AND METHODS

Mouthguards were thermoformed using 4.0-mm-thick ethylene-vinyl-acetate sheets and a vacuum forming device. Square sheets were fixed with the square frame of the forming device. Circular sheets were fixed to the forming device with a circular frame. The model was placed with its anterior rim positioned 40, 30, 20, or 10 mm from the front of the forming table. The model position was marked on the forming table so that it was constant under each condition. Six mouthguards were fabricated for each condition. Mouthguard thicknesses of the incisal edge, labial and buccal surfaces, and the cusp were measured. Differences in the rate of thickness reduction due to frame shapes and model positions were analyzed by two-way ANOVA.

RESULTS

Difference in the thickness reduction rate depending on the frame shape was observed on the labial and buccal surfaces, and it was significantly greater with the circular frame than with the square frame (p < .01). In the anterior region, the thickness reduction rate tended to increase as the model position was moved toward the front of the forming table. The thickness reduction rate of the posterior portion was lowest when the model's molar was positioned at the center of the forming table.

CONCLUSIONS

The labial thickness of the mouthguard was not affected by the frame shape if the distance from the model to the frame was larger than the model height. However, the buccal thickness was thinner with the circular frame than with the square frame regardless of the model position.

Minimally invasive approach supported by the use of mouthguard in the treatment of sport-related root fracture: a case report

All sporting activities have an associated risk of orofacial injuries that can affect the oral health-related quality of life (OHRQoL). A custom-made mouthguard can be used as an adjuvant treatment for faster recovery of an athlete to resume sporting activities. This case report described a minimally invasive approach by use of mouthguard for treating sport-related root fracture and its impact on OHRQoL. In a dental trauma care program, the patient was treated by repositioning the coronary portion and the confection of a splint. It was opted to not realize the endodontic treatment and the patient was inserted in a rigorous clinical and radiographic follow-up. A custom-made mouthguard was made, which allowed for the immediate return of athletes to practicing sports. The athlete's OHRQoL was negatively impacted by dental trauma, but the treatment proposed was associated with the use of custom-made mouthguards. After 2 years, the absence of radiographical lesions and a positive response to sensibility tests were observed. The success of the minimally invasive approach was attributed to immediate conduct following dental trauma, the implementation of follow-up, and associated with the use of custom-made mouthguard.

Athletes' and Coaches' Attitudes Toward Protective Headgear as Concussion and Head Injury Prevention: A Scoping Review

The purpose of this article is to map existing research literature on athletes and coaches' attitudes toward protective headgear in sport in relation to concussion and head injury prevention, and to identify and analyse knowledge gaps in the field. A scoping review was conducted in three databases; PubMed, Scopus, SportDiscus, and reference lists were searched to identify relevant grey literature. This process lead to an in-depth analysis of 18 peer-reviewed journal articles. Of the 18 studies identified, the majority focused on athletes (n = 14), only two studies focused on coaches, and two studies included a sample of both athletes and coaches. The findings in this scoping review suggests that there is a discrepancy between attitudes and beliefs about the protective effects of headgear, athletes' behaviour as far as wearing protective headgear, and coaches' behaviour in terms of recommending use of protective headgear to their athletes. The majority of athletes in most of the reviewed literature believed that headgear had protective effects against concussion and other head injuries, however relatively few athletes report wearing this protective headgear unless it was mandatory by competition rules.

Prevalence of orofacial trauma and the attitude towards mouthguard use in handball players: A survey in Lorraine, France

BACKGROUND/AIMS

Contact sports such as handball may lead to orofacial injuries that can often be prevented by the use of a properly fitted mouthguard. Several studies have investigated orofacial injuries during contact sports in different countries, but there is a lack of data that is specific for French handball players. Therefore, the aims of this study were to determine the prevalence of orofacial injuries and the proportion of handball players using a mouthguard in Eastern France.

MATERIAL AND METHODS

Data were collected from handball players aged over 15 years old from five handball clubs in the Lorraine Region (Eastern France). A questionnaire containing 26 questions about the general characteristics of participants, orofacial injury experiences, emergency procedures following tooth avulsion, and use of mouthguards was self-administered.

RESULTS

Two hundred and sixty-three handball players, of which 76.8% (202) were males, aged 23 ± 8 years on average, with a mean playing experience of 11 ± 6 years, participated in the study. Among them, 24.7% (65) reported at least one orofacial injury. A total of 237 orofacial injuries was declared. The main types of orofacial injuries including lip, cheek and tongue injuries were reported by 18.6% of handball players (49); dental injuries were reported by 9.9% (26) and injuries to the temporomandibular joint were reported by 4.9% (13). Most participants knew about mouthguards (97.3%, 254) and considered them efficient for preventing dental injuries in handball (95.3%, 242/254), but only 3.0% (8) used them.

CONCLUSION

The prevalence of orofacial injuries among French handball players was high while mouthguards were very rarely used. Information should be provided to handball teams regarding mouthguard use and the management of dental injuries.

Investigating the effect of mouth guard use on aerobic performance in amateur boxers

Objectives

To assess if wearing a mouth guard impacts maximal aerobic capacity in amateur boxers.

Materials and Methods

A prospective crossover cohort (pilot) study was conducted to assess maximal aerobic capacity in amateur boxers using the 20 m multi stage fitness test (MSFT). Two primary outcomes measures were recorded: (1) the maximum oxygen uptake (peak VO₂—mL/kg/min) and (2) distance run (meters—m). Thirteen amateur boxers completed the MSFT 7 days apart under control (no mouth guard—C) and intervention conditions (mouth guard—MG). Participants also submitted data on height, weight, type of mouth guard and Rate of Perceived Exertion (RPE) during the test.

Statistics

Paired T‐test.

Results

Mouth guard use was shown to reduce peak VO₂ and distance run during the 20 m MSFT from 56.31 to 54.12 mL/kg/min and 2572 to 2380 m respectively (p < 0.05). Twelve out of 13 participants wore a Boil & Bite mouthguard and recorded lower peak VO₂ scores (−4.38%) when wearing a mouth guard compared to control conditions, (Mean = −2.46 mL/kg/min, Range of decrease = 4.2–0.9 mL/kg/min; p < 0.05). Ten participants submitted data on RPE—One participant with a custom made mouthguard reported no change in RPE in mouthguard conditions, while nine participants reported an average (+30.5%) increase in mean RPE in Boil & Bite mouthguard conditions compared to control conditions.

Conclusions

Boil & Bite mouth guard use was shown to significantly reduce aerobic performance in amateur boxers and increase the perceived rate of exertion during the 20 m MSFT.

Thickness change and deformation of custom-made mouthguards after two years of use by Bangladeshi field hockey players

BACKGROUND/AIM

Sports mouthguards are effective devices that prevent dental trauma in sports activities. Players should change mouthguards on a regular basis because of thickness reduction and shape deformation. However, there is no guidance regarding the best timing to change mouthguards. The aims of this study were to analyze the thickness change and deformation of mouthguards after 2 years of use in Bangladesh field hockey players and to consider appropriate evaluation criteria.

MATERIAL AND METHODS

Fifty-seven field hockey players belonging to the Bangladesh Sports Education Institute participated in this study. Participants were provided with double-layered mouthguards made of polyolefin-based material using a vacuum-forming machine. Mouthguards were fabricated using 2-mm-thick sheet as the first layer and 3-mm-thick sheet as the second layer. Players used the mouthguards for 2 years. Before and after using the mouthguards, the thicknesses of nine areas were measured. In addition, the lengths of five areas were used to analyze shape deformation.

RESULTS

After 2 years, the thicknesses of all measured areas had significantly reduced, and the lengths had significantly increased. Thickness reduction of the posterior-occlusal and anterior-incisal areas and deformation of the posterior-buccal and posterior-palatal areas were significantly larger than those in other measured areas.

CONCLUSIONS

Mouthguards should be changed on a regular basis to minimize thickness reduction and deformation. Occlusal and incisal thickness and length of the buccal-posterior area and the palatal-posterior area are factors to be considered in establishing guidelines regarding the timing of mouthguard change.

Effect on thickness of a single-layer mouthguard of positional relationship between suction port of the vacuum forming device and the model

BACKGROUND/AIM

Wearing a mouthguard reduces the risk of sport-related injuries, but the thickness has a large effect on its efficacy and safety. The aim of this study was to investigate the effect on the thickness of a single-layer mouthguard of the positional relationship between the suction port of the vacuum forming device and the model.

MATERIALS AND METHODS

Ethylene-vinyl-acetate sheets of 4.0-mm-thickness and a vacuum forming machine were used. Two hard plaster models were prepared: Model A was 25-mm at the anterior teeth and 20-mm at the molar, and model B was trimmed so the bucco-lingual width was half that of model A. Three model positions on the forming table were examined: (a) P20, where the model anterior rim was located in front of the suction port, (b) P30, where the model anterior rim and front edge of the suction port were close, and (c) P43, where the model anterior rim and palatal rim were located on the suction port. Six mouthguards were fabricated for each condition. Thickness differences due to model form and model position were analyzed.

RESULTS

Thickness differences due to model form were observed at the incisal edge and labial surface, and model A was significantly thicker than model B in P43 (P<.01). The thickness of the incisal edge and labial surface was significantly greatest in P43 for model A, but in P30 for model B.

CONCLUSIONS

The effect of the model position on the forming table on suppressing the labial thickness reduction of the mouthguard depended on the bucco-lingual width of the model. It is important to position the model anterior rim away from the sheet frame if the bucco-lingual width of the model is large and to place the model anterior rim in front of the suction port if the width is small.

Difference in laminated mouthguard thickness according to the laminate order

BACKGROUND/AIM

Mouthguard thickness should be maintained to prevent oral trauma by protecting the teeth and the surrounding soft tissue. The aim of this study was to examine the difference in laminated mouthguard thickness according to the laminate order.

MATERIALS AND METHODS

The mouthguard sheets used in this study were 2.0 mm and 3.0 mm ethylene-vinyl acetate. The sheets were pressure-formed using a pressure former, and the laminated mouthguard was fabricated. Two laminate conditions were examined. One condition used the 2.0-mm sheet for the first layer and the 3.0-mm sheet for the second layer (condition 2F3S) and the other condition used the 3.0-mm sheet for the first layer and 2.0-mm sheet for the second layer (condition 3F2S). The first layer was trimmed to cover the labial surface and incisal edge of the anterior teeth and the buccal and occlusal surfaces of the posterior teeth. The second layer was formed over the first layer. The mouthguard thickness was measured at the labial surface of the central incisor and the buccal and occlusal surfaces of the first molar. Differences in thickness by measurement region of mouthguards formed under different laminate conditions were analyzed by two-way analysis of variance.

RESULTS

The mouthguard thickness was significantly different at the measured regions of the central incisors and the first molars (p < .01). The thickness at the labial surface of the central incisor and at the buccal and occlusal surfaces of the first molar became statistically significantly larger with the 3F2S condition than that for the 2F3S condition (p < .05 or p < .01).

CONCLUSIONS

The thickness of the laminated mouthguard became larger when the sheet thickness of the first layer was greater. It is recommended to use the thicker mouthguard sheet as the first layer when fabricating a laminated mouthguard.

Oral management with mouthguards during the mixed dentition period: A case report

Custom-made mouthguards are widely used by athletes during training and sporting events for the prevention of oral injuries. However, even though the prevalence of dental injuries in children in the primary or mixed dentition stages is high, few reports have focused on mouthguard use for such cases due to the difficulties associated with adapting them as teeth are lost and replaced. This report presents a case of a Japanese boy in the mixed dentition stage with a custom-made mouthguard. For fabrication, self-curing acrylic resin was used to fill portions of a working model to keep space for the later eruption of permanent teeth. However, adjustment was necessary when gingival swelling occurred in association with maxillary canine eruption, after which refabrication was necessary. Regular management of a custom-made mouthguard by the attending dentist is important for children in the mixed dentition period, especially during maxillary canine eruption, which causes drastic dentition changes. In the present case, custom-made mouthguards were fully effective based on the prediction of changes in the dentition and with regular dental management.