The use of a custom-made mouthguard stabilizes the electromyographic activity of the masticatory muscles among Karate-Dō athletes

Acute effects of jaw clenching while wearing a customized bite-aligning mouthguard on muscle activity and force production during maximal upper body isometric strength

Background/objectives

The possible mechanisms supporting the relationship between the masticatory and the musculoskeletal systems have been recently investigated. It has been suggested that jaw clenching promotes ergogenic effects on prime movers through the phenomenon of concurrent activation potentiation (CAP). The purpose of this study was to analyse the effects of jaw clenching and jaw clenching while wearing mouthguard (MG) on muscle activity and force output during three upper body isometric strength tests.

Methods

Twelve highly trained rink-hockey athletes were recruited for the study. A randomized, repeated measures within study design was carried out to compare the acute effects of three experimental conditions: jaw clenching while wearing MG (MG), jaw clenching without MG (JAW) and non-jaw clenching (NON-JAW).

Results

Statistical analyses revealed significant higher force output (p < 0.05) in all tests for MG conditions with respect to NON-JAW. When comparing JAW and NON-JAW conditions an increased peak force was found in handgrip (p = 0.045, d = 0.26) and bench press (p = 0.018, d = 0.43) but not in biceps curl (p = 0.562, d = 0.13). When comparing MG and JAW conditions, no differences were observed in any force output. In terms of muscle activity, significant differences were found in the agonist muscles of the handgrip test for MG with respect to NON-JAW (p = 0.031-0.046, d = 0.25-1.1).

Conclusion

This study demonstrated that jaw clenching, with and without MG, may be a good strategy to elicit the CAP phenomenon, which seems to promote ergogenic effects in upper body isometric force production. The non-significant differences observed between JAW and MG suggested that the use of MG doesn't make a difference in enhancing the isometric force production neither the muscle activity in upper body isometric strength.

The Impact of Sport Training on Oral Health in Athletes

Athletes' oral health appears to be poor in numerous sport activities and different diseases can limit athletic skills, both during training and during competitions. Sport activities can be considered a risk factor, among athletes from different sports, for the onset of oral diseases, such as caries with an incidence between 15% and 70%, dental trauma 14-70%, dental erosion 36%, pericoronitis 5-39% and periodontal disease up to 15%. The numerous diseases are related to the variations that involve the ecological factors of the oral cavity such as salivary pH, flow rate, buffering capability, total bacterial count, cariogenic bacterial load and values of secretory Immunoglobulin A. The decrease in the production of S-IgA and the association with an important intraoral growth of pathogenic bacteria leads us to consider the training an "open window" for exposure to oral cavity diseases. Sports dentistry focuses attention on the prevention and treatment of oral pathologies and injuries. Oral health promotion strategies are needed in the sports environment. To prevent the onset of oral diseases, the sports dentist can recommend the use of a custom-made mouthguard, an oral device with a triple function that improves the health and performance of athletes. During training, the sports dentist must monitor the athletes and the sports examination protocol must be implemented with the inclusion of the clinical examination, quantitative and qualitative analysis of saliva and instructions on the use, cleansing and storage of the mouthguard.

Mouthguard-effect of high-intensity weight training on masticatory muscle tone and stiffness in taekwondo athletes

This study aimed to analyze the effect of wearing a mouthguard or not on masticatory muscle tone and stiffness of male taekwondo athletes during high-intensity weight training. The participants were male taekwondo athletes and aged 18 to 22 years. We randomly divided 24 men into the control group (CON; without a mouthguard; n=12) and the experimental group (MOG; with a mouthguard; n=12). Masticatory muscle tone and stiffness were measured after weight training at a level of 70% of one-repetition maximum. As a result of this study, masticatory muscle tone was no different in intragroup and intergroup after experiment. In addition, although the masticatory muscle stiffness was significantly higher in the dominant side of the MOG, there was no difference in intergroup, intragroup, and interaction. Through this study, it is necessary to consider the selective wearing of a mouthguard according to the training methods when partially analyzed from the physiological point of view of the masticatory muscle of taekwondo athletes.

Influence of a Vented Mouthguard on Physiological Responses in Handball

Schulze, A, Laessing, J, Kwast, S, and Busse, M. Influence of a vented mouthguard on physiological responses in handball. J Strength Cond Res 34(7): 2055-2061, 2020-Mouthguards (MGs) improve sports safety. However, airway obstruction and a resulting decrease in performance are theoretical disadvantages regarding their use. The study aim was to assess possible limitations of a "vented" MG on aerobic performance in handball. The physiological effects were investigated in 14 male professional players in a newly developed handball-specific course. The measured values were oxygen uptake, ventilation, heart rate, and lactate. Similar oxygen uptake (V[Combining Dot Above]O2) values were observed with and without MG use (51.9 ± 6.4 L·min·kg vs. 52.1 ± 10.9 L·min·kg). During maximum load, ventilation was markedly lower with the vented MG (153.1 ± 25 L·min vs. 166.3 ± 20.8 L·min). The endexpiratory concentrations of O2 (17.2 ± 0.5% vs. 17.6 ± 0.8%) and CO2 (4.0 ± 0.5% vs. 3.7 ± 0.6%) were significantly lower and higher, respectively, when using the MG. The inspiration and expiration times with and without the MG were 0.6 ± 0.1 seconds vs. 0.6 ± 0.1 seconds and 0.7 ± 0.2 seconds vs. 0.6 ± 0.2 seconds (all not significant), respectively, indicating that there was no relevant airflow restriction. The maximum load was not significantly affected by the MG. The lower ventilation for given V[Combining Dot Above]O2 values associated with MG use may be an effect of improved biomechanics and lower respiratory drive of the peripheral musculature.

Development and Implementation of an Intraoral Device for Occlusal Stability during Sports Performance: A Case Report

INTRODUCTION

Sports dentistry assumes a clinical relevance, not only in the prevention of orofacial trauma by the use of mouthguards, but also with the development of intraoral devices that aim to provide greater occlusal stability, as well as a greater balance in the level of certain structures of the cranio-cervical-mandibular complex. In this way, the dentistry can have an intervention action on sports performance.

OBJECTIVES

The objective of this research was to verify the existence of a correlation between occlusal stability and an eventual balance of some facial structures during sports performance using a specially developed Occlusal Stability Sports Performance Device.

METHODOLOGY

An individualized mandibular intraoral device was manufactured and evaluated on an athlete canoeing. Infrared thermography was the complementary diagnostic method used for this purpose.

RESULTS

Greater symmetry of certain regions of interest of the cranio-cervico-mandibular complex was observed with the implementation of the Occlusal Stability Sports Performance Device. These areas were the anterior temporal muscle, the masseter muscle and the temporomandibular joint. No asymmetry decrease was found in the anterior triangle region of the neck.

CONCLUSION

The use of this type of intraoral devices may allow greater occlusal stability and consequent balance of anatomical structures constituting the cranio-cervical-mandibular complex. Infrared thermography is an effective diagnostic tool for studying the results of the intraoral device on the cranio-cervico-mandibular complex use during canoeing.