Effect of thickness and occlusal accommodation on the degree of satisfaction with mouthguard use among water polo players: A randomized crossover trial

Influence of Using a Puncturing Method and Cooldown Period Before Pressing the Second-Layered Sheet on the Final Thickness of Double-Layered Sports Mouthguards: An Experimental Study

AIM

The thickness of the mouthguard is a crucial factor in its protective ability for athletes. This study aimed to investigate the final thickness of double-layered sports mouthguards, which were fabricated using different methods before pressing the second layer.

MATERIALS AND METHODS

Seven upper working models (n = 7 per group) were prepared for mouthguard fabrication. The first 3-mm mouthguard sheet underwent heating, pressing, and vacuuming onto the model, followed by various protocols before the second 3-mm sheet was pressed. Group 1: The second sheet was pressed immediately. Group 2: The first sheet underwent a 1-h cooldown period before pressing the second sheet. Group 3: The interproximal areas of the first sheet were punctured followed by immediate pressing of the second sheet. Group 4: The first sheet was punctured followed by a 1-h cooldown before pressing the second sheet. After 24 h, the mouthguard thickness was measured at various points on the left and right central incisors and first molars using a digital caliper. The thickness analysis was performed using SPSS 29.0 with one-way ANOVA and Tukey post hoc analysis.

RESULTS

At the labial surface of the central incisors, Group 4 exhibited the highest thickness, while Group 3 had the lowest (p < 0.001). Groups 1 and 2 did not show significant differences in thickness. At the incisal edges, Group 3 again had the lowest thickness (p < 0.05), with no significant differences observed among the other groups. There were no significant differences in thickness across all areas at the first molars, including cusp tips, pits, and buccal surfaces (p > 0.05). Group 4 demonstrated greater uniformity at the central incisors in thickness compared with the other groups.

CONCLUSIONS

Using the puncturing method at interproximal areas combined with a cooldown period could enhance mouthguard thickness at the labial surfaces of the central incisors and improve its thickness uniformity.

Adaptation and Biomechanical Performance of Custom-Fit Mouthguards Produced Using Conventional and Digital Workflows: A Comparative In Vitro Strain Analysis

BACKGROUND/OBJECTIVES

The use of different models for the fabrication of custom-fit mouthguards (MTGs) can affect their final thickness, adaptation, and shock-absorption properties. This study aimed to evaluate the adaptation, thickness, and shock absorption of ethylene-vinyl acetate (EVA) thermoplastic MTGs produced using conventional plaster or three-dimensional (3D) printed models.

MATERIALS AND METHODS

A typical model with simulated soft gum tissue was used as the reference model to produce MTGs with the following two different protocols: plast-MTG using a conventional impression and plaster model (n = 10) and 3DPr-MTG using a digital scanning and 3D printed model (n = 10). A custom-fit MTG was fabricated using EVA sheets (Bioart) plasticized over different models. The MTG thickness (mm), internal adaptation (mm) to the typodontic model, and voids in the area (mm2) between the two EVA layers were measured using cone-beam computed tomography images and Mimics software (Materialize). The shock absorption of the MTG was measured using a strain-gauge test with a pendulum impact at 30° with a steel ball over the typodont model with and without MTGs. Data were analyzed using one-way analysis of variance with repeated measurements, followed by Tukey's post hoc tests.

RESULTS

The 3DPr-MTG showed better adaptation than that of the Plast-MTG at the incisal/occlusal and lingual tooth surfaces (p < 0.001). The 3DPr-MTG showed a thickness similar to that of the Plast-MTG, irrespective of the measured location. MTGs produced using both model types significantly reduced the strain values during horizontal impact (3DPr-MTG 86.2% and Plast-MTG 87.0%) compared with the control group without MTG (p < 0.001).

CONCLUSION

The MTGs showed the required standards regarding thickness, adaptation, and biomechanical performance, suggesting that the number and volume of voids had no significant impact on their functionality. Three-dimensional printed models are a viable alternative for MTG production, providing better adaptation than the Plast-MTG at the incisal/occlusal and lingual tooth surfaces and similar performance as the MTG produced with the conventional protocol.

Digital workflow for the fabrication of custom-fit additively manufactured sports mouthguards with balanced occlusion using an optical jaw tracking system: A dental technique

Custom sports mouthguards are used in various sports to protect teeth, temporomandibular joints, and soft tissues from impact forces. The present article demonstrates a digital workflow to fabricate a 3-dimensionally (3D) printed individualized sports mouthguard. An optical jaw tracking system is used to record a repeatable reference position, and mandibular excursive movements to achieve a completely balanced occlusion. The technique simplifies the fabrication of a custom-fit mouthguard over the conventional approach by providing increased thickness accuracy, control of design, and integration of jaw motion.

Changes in oral functions and speech when using custom-fitted mouthguards: An uncontrolled before-and-after study

BACKGROUND/AIM

Mouthguards are crucial for protecting athletes against orofacial injuries, yet concerns persist regarding their potential impact on oral functions. This study aimed to investigate the effects of sports mouthguards on oral functions and speech over time.

MATERIAL AND METHODS

Thirty national rugby players received custom-fitted mouthguards. Questionnaire responses and speech recordings were collected before mouthguard use and at various intervals after using mouthguards: immediately, 1 week, 2 month, and 6 months. Spectrographic analysis was performed to measure voice onset time (VOT) for /p, b, t, d/ phonemes. Questionnaire responses were assessed with Friedman's test, while VOT changes were examined using one-way repeated measure analysis of variance.

RESULTS

Compliance with mouthguard use improved during training and competitions, with consistent wear reported during matches. Over time, speaking difficulties and lisping decreased significantly (p < .001). The perception of nausea improved (p < .001), stabilizing after 1 month (p = .414). Sensations of bulkiness declined (p < .001). Mouth dryness reduced steadily, with no occurrences reported by all players by the end of the study. None of the participants reported bad breath, ulcers, or redness in the mouth. VOT changed immediately after wearing mouthguards (p < .001), gradually regressing toward the baseline, although not completely reaching it. Players held a favorable view of mouthguard use, with comfort and support for mandatory use increasing over time.

CONCLUSIONS

Custom-fitted mouthguards do not lead to significant long-term disruptions in oral functions. Athletes generally adapt to mouthguard use, reporting improved comfort and greater support for their use.

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.

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.

Effects of different custom-made mouthguard palatal extensions on the stress-state of dentoalveolar structures: a 3D-FEA

OBJECTIVES

The present study aimed to simulate the influence of palatal extensions for custom-made mouthguards (MGs) on protecting dentoalveolar structures and to provide a theoretical basis for designing a comfortable MG.

MATERIALS AND METHODS

Based on finite element analysis (3D-FEA), five groups of maxillary dentoalveolar models of wearing MGs were established: no MG on palatal side (NP), on palatal gingival margin (G0), 2 mm from the palatal gingival margin (G2), 4 mm from the palatal gingival margin (G4), 6 mm from the palatal gingival margin (G6), and 8 mm from the palatal gingival margin (G8). A cuboid was created to simulate the solid ground impacted in falls, a gradually increasing force was applied from 0 to 500 N on the vertical ground, and the distribution and peak values of the Critical modified von-Mises stress, maximum principal stress, and displacement of dentoalveolar models were calculated.

RESULTS

Stress distribution range, stress, and deformation peak value of dentoalveolar models increased as the impact strength increased, at 500 N. Maximum critical modified von-Mises stress, peak maximum principal stress and maximum displacement of dentoalveolar models G4, G3, G2, G1, G0, and NP were 154.5 MPa, 154.5 MPa, 154.4 MPa, 154.7 MPa, 154.4 MPa, and 154.7 MPa; 191.65 MPa, 192.11 MPa, 191.62 MPa, 191.81 MPa, 191.56 MPa, and 191.62 MPa; and 88.78 μm, 88.57 μm, 88.19 μm, 88.67 μm, 88.43 μm, and 89.04 μ, respectively. However, the position of the MG palatal edge had little effect on stress distribution, stress, and deformation peak values of the dentoalveolar models.

CONCLUSIONS

Different extension ranges of the MG palatal edge have little effect on the protective effects of MGs on maxillary teeth and maxilla. An MG with palatal extension on the gingival margin is more appropriate than other models and may help dentists to design a suitable MG and increase its usage.

CLINICAL RELEVANCE

MGs with palatal extensions on the gingival margin may provide a more comfortable wearing experience for individuals involved in sports and encourage increased MG usage.

Attitudes and opinions towards the prevention of orofacial injuries among water polo coaches in Catalonia: A cross-sectional study

BACKGROUND/AIM

Although orofacial injuries are frequent in water polo, fewer than 10% of players use mouthguards. The aim of this study was to determine the degree to which coaches and sports club managers encourage mouthguard use in water polo and to explore their opinions regarding other strategies designed to reduce the prevalence of orofacial injuries.

MATERIAL AND METHODS

This was a cross-sectional study in which the coaches and sports club managers of 16 water polo clubs in Catalonia were invited to participate. An online questionnaire was administered to the coaches to obtain general data, to determine whether they had recommended mouthguard use to their players and to record their opinions on other strategies designed to reduce the prevalence of orofacial injuries. Sports club managers were interviewed about the facilities offered by their clubs for players to obtain mouthguards and about their attitudes regarding the prevention of orofacial injuries.

RESULTS

The questionnaire was administered to 72 coaches who trained 111 teams during the 2019-2020 season, together with 14 sports club managers. Coaches of only 11 teams (10%) recommended mouthguard use to their players. Two clubs (14%) offered some facilities to their players to obtain mouthguards. Interestingly, only 18% of the coaches believed that mouthguard use should be mandatory, in contrast to 50% of the sports club managers (p = 0.017; Fisher's exact test). Most coaches and sports club managers believe that a video monitoring system should be used to identify dangerous play and that orofacial injuries should be reported under a surveillance programme.

CONCLUSIONS

Few water polo coaches recommend mouthguard use to their players and very few clubs offer facilities to obtain custom-made oral protection. However, most coaches and sports club managers agree that the rules should be modified to protect players from aggressive play.