The production and materials of mouthguards: Conventional vs additive manufacturing - A systematic review.

This investigation presents a critical analysis of mouthguard production, focusing on the evaluation of conventional vs additive manufacturing methods, the materials involved, and aspects such as their failure and prevention. It also summarizes the current trends, perspectives, and the main limitations. It is shown that some of the shortcomings can be solved by implementing additive manufacturing technologies, which are systematically reviewed in this research. Due to the specific materials used to produce mouthguards, there are certain additive manufacturing technologies that dominate and a wide variety of raw materials. The costs vary depending on the technology.

Stress Distribution Pattern of a Calculated Standardized Force on Maxillary and Mandibular Jaws with Proclined Maxillary Anterior Teeth with and without the Use of Mouthguard: A 3D Finite Element Analysis.

Aim: To evaluate the stress distribution of calculated standardized force on maxillary and mandibular jaw bones with proclined maxillary anterior teeth with and without the use of a mouthguard. Materials and methods: It's a finite element analysis (FEA) study. Maxillary and mandibular jaw models with and without mouthguard (4 mm) were created using a cone-beam computed tomography (CBCT) scan of a 13-year-old male patient with proclined maxillary anterior teeth. Calculated standardized forces were applied on the maxillary central incisors in the horizontal direction of the created model. The von Mises stresses (MPa) were analyzed on the maxillary and mandibular jaw. Results: Higher von Mises stresses were analyzed in the maxillary and mandibular jaw model without a mouthguard compared to the model with a mouthguard. Forces were more evenly distributed in the maxillary and mandibular jaw models with a mouthguard. Conclusion: A mouthguard can be used to reduce and evenly distribute the stress on the maxillary and mandibular jaw with proclined maxillary anterior teeth when exposed to real-life situation forces. Clinical significance: The force of injury is influenced by the size of the object or the velocity at which the athlete hits the object/individual. There is a need to evaluate the force at which the individual athlete hits the object/surface based on average height, weight, and velocity/performance at that particular age. As the age of the athlete's advances, there is a change in the height, weight as well as performance. This factor will influence the impact and severity of the trauma caused during sports activities. So, these parameters should be considered while designing the mouthguard for its better effectiveness. How to cite this article: Doiphode AR, Kalaskar R. Stress Distribution Pattern of a Calculated Standardized Force on Maxillary and Mandibular Jaws with Proclined Maxillary Anterior Teeth with and without the Use of Mouthguard: A 3D Finite Element Analysis. Int J Clin Pediatr Dent 2024;17(S-1):S61-S66.

Prevention of Oral Injuries during Endotracheal Intubation: Patients' and Anesthesiologists' Perspective.

OBJECTIVE: The aim was to design accessible, simple, inexpensive protection for teeth and soft tissues during ETI, compare damage occurrence with and without protection, and investigate post-ETI orofacial pain symptoms. MATERIALS AND METHODS: The selection procedure for adequate protection was carried out after which a reduced elastomer mouthguard was selected. Fifty patients were divided into 2 groups. In the first group, ETI was carried out using a mouthguard, while in the second group it was performed without it. The mouthguard was fabricated by anesthesiologists. After the ETI procedure, the patients and anesthesiologists were asked to complete a survey. RESULTS: No difference in intubation severity and time required for intubation between the two groups was present. Seven patients from the non-mouthguard group suffered injuries during the ETI procedure. No injuries were present in the mouthguard group. In 92% of cases anesthesiologists agreed that mouthguards should be used during ETI. However, most of them (96% of cases) agree that the mouthguard should be used only when there is an increased risk of tooth loss and/or tooth damage. There was a significant ETI effect on the emergence of new orofacial pain cases. CONCLUSION: The mouthguard adequately protected dental and soft tissues and did not affect the work of the anesthesiologist. A significantly higher number of patients experiencing temporomandibular joint and masticatory muscles pain after surgery indicates that ETI might be a risk factor for orofacial pain.

Instrumented Mouthguard Decoupling Affects Measured Head Kinematic Accuracy.

Many recent studies have used boil-and-bite style instrumented mouthguards to measure head kinematics during impact in sports. Instrumented mouthguards promise greater accuracy than their predecessors because of their superior ability to couple directly to the skull. These mouthguards have been validated in the lab and on the field, but little is known about the effects of decoupling during impact. Decoupling can occur for various reasons, such as poor initial fit, wear-and-tear, or excessive impact forces. To understand how decoupling influences measured kinematic error, we fit a boil-and-bite instrumented mouthguard to a 3D-printed dentition mounted to a National Operating Committee on Standards for Athletic Equipment (NOCSAE) headform. We also instrumented the headform with linear accelerometers and angular rate sensors at its center of gravity (CG). We performed a series of pendulum impact tests, varying impactor face and impact direction. We measured linear acceleration and angular velocity, and we calculated angular acceleration from the mouthguard and the headform CG. We created decoupling conditions by varying the gap between the lower jaw and the bottom face of the mouthguard. We tested three gap conditions: 0 mm (control), 1.6 mm, and 4.8 mm. Mouthguard measurements were transformed to the CG and compared to the reference measurements. We found that gap condition, impact duration, and impact direction significantly influenced mouthguard measurement error. Error was higher for larger gaps and in frontal (front and front boss) conditions. Higher errors were also found in padded conditions, but the mouthguards did not collect all rigid impacts due to inherent limitations. We present characteristic decoupling time history curves for each kinematic measurement. Exemplary frequency spectra indicating characteristic decoupling frequencies are also described. Researchers using boil-and-bite instrumented mouthguards should be aware of their limitations when interpreting results and should seek to address decoupling through advanced post-processing techniques when possible.

All-in-One, Wireless, Multi-Sensor Integrated Athlete Health Monitor for Real-Time Continuous Detection of Dehydration and Physiological Stress.

Athletes are at high risk of dehydration, fatigue, and cardiac disorders due to extreme performance in often harsh environments. Despite advancements in sports training protocols, there is an urgent need for a non-invasive system capable of comprehensive health monitoring. Although a few existing wearables measure athlete's performance, they are limited by a single function, rigidity, bulkiness, and required straps and adhesives. Here, an all-in-one, multi-sensor integrated wearable system utilizing a set of nanomembrane soft sensors and electronics, enabling wireless, real-time, continuous monitoring of saliva osmolality, skin temperature, and heart functions is introduced. This system, using a soft patch and a sensor-integrated mouthguard, provides comprehensive monitoring of an athlete's hydration and physiological stress levels. A validation study in detecting real-time physiological levels shows the device's performance in capturing moments (400-500 s) of synchronized acute elevation in dehydration (350%) and physiological strain (175%) during field training sessions. Demonstration with a few human subjects highlights the system's capability to detect early signs of health abnormality, thus improving the healthcare of sports athletes.

On-Field Evaluation of Mouthpiece-and-Helmet-Mounted Sensor Data from Head Kinematics in Football.

PURPOSE: Wearable sensors are used to measure head impact exposure in sports. The Head Impact Telemetry (HIT) System is a helmet-mounted system that has been commonly utilized to measure head impacts in American football. Advancements in sensor technology have fueled the development of alternative sensor methods such as instrumented mouthguards. The objective of this study was to compare peak magnitude measured from high school football athletes dually instrumented with the HIT System and a mouthpiece-based sensor system. METHODS: Data was collected at all contact practices and competitions over a single season of spring football. Recorded events were observed and identified on video and paired using event timestamps. Paired events were further stratified by removing mouthpiece events with peak resultant linear acceleration below 10 g and events with contact to the facemask or body of athletes. RESULTS: A total of 133 paired events were analyzed in the results. There was a median difference (mouthpiece subtracted from HIT System) in peak resultant linear and rotational acceleration for concurrently measured events of 7.3 g and 189 rad/s2. Greater magnitude events resulted in larger kinematic differences between sensors and a Bland Altman analysis found a mean bias of 8.8 g and 104 rad/s2, respectively. CONCLUSION: If the mouthpiece-based sensor is considered close to truth, the results of this study are consistent with previous HIT System validation studies indicating low error on average but high scatter across individual events. Future researchers should be mindful of sensor limitations when comparing results collected using varying sensor technologies.

Biofidelity and Limitations of Instrumented Mouthguard Systems for Assessment of Rigid Body Head Kinematics.

Instrumented mouthguard systems (iMGs) are commonly used to study rigid body head kinematics across a variety of athletic environments. Previous work has found good fidelity for iMGs rigidly fixed to anthropomorphic test device (ATD) headforms when compared to reference systems, but few validation studies have focused on iMG performance in human cadaver heads. Here, we examine the performance of two boil-and-bite style iMGs in helmeted cadaver heads. Three unembalmed human cadaver heads were fitted with two instrumented boil-and-bite mouthguards [Prevent Biometrics and Diversified Technical Systems (DTS)] per manufacturer instructions. Reference sensors were rigidly fixed to each specimen. Specimens were fitted with a Riddell SpeedFlex American football helmet and impacted with a rigid impactor at three velocities and locations. All impact kinematics were compared at the head center of gravity. The Prevent iMG performed comparably to the reference system up to ~ 60 g in linear acceleration, but overall had poor correlation (CCC = 0.39). Prevent iMG angular velocity and BrIC generally well correlated with the reference, while underestimating HIC and overestimating HIC duration. The DTS iMG consistently overestimated the reference across all measures, with linear acceleration error ranging from 10 to 66%, and angular acceleration errors greater than 300%. Neither iMG demonstrated consistent agreement with the reference system. While iMG validation efforts have utilized ATD testing, this study highlights the need for cadaver testing and validation of devices intended for use in-vivo, particularly when considering realistic (non-idealized) sensor-skull coupling, when accounting for interactions with the mandible and when subject-specific anatomy may affect device performance.

Protein Deposition on Sport Mouthguards and the Effectiveness of Two Different Cleaning Protocols.

Objective: To determine which salivary proteins adhere onto sport mouthguards, and to evaluate the effectiveness of different cleaning strategies in removing deposited protein. Methods: Fifteen healthy volunteers used a mouthguard for 1 h. The deposited salivary proteins were analyzed using gel electrophoresis and Western blotting techniques and compared with the protein composition of unstimulated saliva. In addition, the effectiveness of two different cleaning strategies to remove proteins from the mouthguards were compared: rinsing the mouthguards after use with cold tap water and cleaning the mouthguard with a soluble effervescent tablet. Results: Gel electrophoresis showed deposition of proteins of 50-60 kDa and 14 kDa on the mouthguards used in the mouth for 1 h. Western blotting identified these bands as amylase and lysozyme, respectively. Rinsing the mouthguard with cold tap water after use removed 91% of the total amount of deposited proteins, while cleaning with an effervescent tablet removed 99%. Conclusions: During the use of mouthguards, salivary proteins are deposited on their surface. Because salivary proteins can potentially affect bacterial adhesion to mouthguards, proper cleaning after use is recommended. Cleaning the mouthguard with cold tap water or using an effervescent tablet both seem to be effective strategies to remove proteins deposited on sport mouthguards.

Design of Customized Mouthguards with Superior Protection Using Digital-Based Technologies and Impact Tests.

BACKGROUND: In contact sports, an impact on the jaw can generate destructive stress on the tooth-bone system. Mouthguards can be beneficial in reducing the injury risk by changing the dynamics of the trauma. The material properties of mouthguards and their geometrical/structural attributes influence their protective performance. Custom-made mouthguards are the gold standard, and different configurations have been proposed to improve their protection and comfort. However, the effects of different design variables on the performance of customized mouthguards are not well understood. RESULTS: Herein, we developed a reliable finite element model to analyze contributing factors to the design of custom-made mouthguards. Accordingly, we evaluated the isolated and combined effect of layers' stiffness, thickness, and space inclusion on the protective capability of customized mouthguards. Our simulations revealed that a harder frontal region could distribute load and absorb impact energy through bending if optimally combined with a space inclusion. Moreover, a softer layer could enlarge the time of impact and absorb its energy by compression. We also showed that mouthguards present similar protection with either permanently bonded or mechanically interlocked components. We 3D-printed different mouthguards with commercial resins and performed impact tests to experimentally validate our simulation findings. The impact tests on the fabricated mouthguards used in this work revealed that significantly higher dental protection could be achieved with 3D-printed configurations than conventionally fabricated customized mouthguards. In particular, the strain on the impacted incisor was attenuated around 50% more with a 3D-printed mouthguard incorporating a hard insert and space in the frontal region than a conventional Playsafe® Heavypro mouthguard. CONCLUSIONS: The protective performance of a mouthguard could be maximized by optimizing its structural and material properties to reduce the risk of sport-related dental injuries. Combining finite element simulations, additive manufacturing, and impact tests provides an efficient workflow for developing functional mouthguards with higher protectiveness and athlete comfort. We envision the future with 3d-printed custom-mouthguards presenting distinct attributes in different regions that are personalized by the user based on the sport and associated harshness of the impact incidences.

Conventional Dental Impressions vs. 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.

Shock absorption and dispersion capability of a novel five-layer mouthguard sheet material.

There is a growing need for a mouthguard sheet material with higher shock absorption and dispersion capacity than those obtained by conventional materials. A five-layer mouthguard sheet material was previously developed using laminated ethylene vinyl acetate and polyolefin copolymer resin. In this study, the shock absorption capacity and dispersion capability of the new sheet material were investigated and compared with those of other materials. Impact testing for the new sheet material showed that the force required to displace the sheet by 1 mm was significantly higher at all thicknesses (p<0.001), whereas the puncture energy and displacement were significantly lower than those for ethylene vinyl acetate (p<0.05). The five-layer mouthguard sheet material successfully absorbed and resisted shock. Therefore, the sheet material potentially increases resistance to applied deformation in teeth and alveolar bone and maintains structure. The five-layer sheet material could expand the range of mouthguard products and help prevent oral trauma.

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 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).

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 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 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 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 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 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).