PURPOSE: A survey was performed to identify the level of mouthguard use, awareness, wearability issues and attitude toward mouthguard among elite Korean Taewondo athletes. MATERIALS AND METHODS: Survey questionnaires were given to 152 athletes participating in the Korea National Taekwondo team selection event for the 2010 Guangzhou Asian Games. Questionnaires consisted of three sections, mouthguard awareness, reasons for not wearing mouthguard and the last section to test the level of acceptance on current mouthguard and when the identified problems were resolved. For analyzing difference among response, chi2 test was used and significant level (alpha) was set up as 0.05. RESULTS: Responses in each of items showed significant difference (P<.001). Majority of response regarding each question: Majority of respondents believed that mouthguard were effective in preventing injuries (36.4%) but the result suggested that the provision of information on mouthguard to athletes was inadequate (44.0%) and the result showed that respondents were not greatly interested or concerned in relation to the mandatory mouthguard rule (31.6%). Although the responses on the level of comfort and wearability of mouthguard were negative (34.8%), athletes were positively willing to wear mouthguard if the problems rectified (51.2%). CONCLUSION: Considering the high level of willingness to wear mouthguard if the problems rectified, it is thought that together with efforts in providing more mouthguard information, the work of sports dentistry to research and improve mouthguard will be invaluable in promoting mouthguard to more athletes.
Asian Continental Ancestry Group ; Athletes ; Dentistry ; Humans ; Korea ; Martial Arts ; Mouth Protectors ; Sports ; Surveys and Questionnaires

STATEMENT OF PROBLEM & PURPOSE: The purpose of this study was to investigate the effect of a mouth guard material properties on the skull and brain when they were under impact loads on mandible. MATERIAL AND METHODS: Two customized mouth protectors having different material propeerst ieach other were made for a female Korean who had no history of brain trauma, no cerebral diseases, nomal occlusion and natural dentition. The 3D finite element model of human skull and brain scanned by means of computed tomography was constructed. The FEM model of head was composed of 407,825 elements and 82,138 nodes, including skull, brain, maxilla, mandible, articular disc, teeth and mouth guard. The stress concentrations on maxillary teeth, maxilla and skull with two mouth guards were evaluated under oblique impact load of 800N onto mandibular 3 loading points for 0.1sec. And the brain relative displacement was compared in two different mouth guard materials under same condition. RESULT AND CONCLUSION: The results were as follows; 1. In comparison of von Mises stress on maxillary teeth, a soft mouth guard material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 2. In comparison of von Mises stress on maxilla and skull, A soft mouth protector material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 3. For impact loads on mandible, there were more stress concentrated area on maxilla and skull with hard mouth guard than soft with mouth protector. 4. For impact loads on mandible, brain relative displacement had little relation with mouth guard material properties. In results of this study, soft mouth guard materials were superior to hard mouth guard materials for mandible impact loads for prevention of sports injuries. Although the results of this study were not enough to figure out the roles of needed mouth guard material properties for a human head, we got some knowledge of the pattern about stress concentration and distribution on maxilla and skull for impact loads with soft or hard mouth protector. More studies are needed to substantiate the relationship between the mouth guard materials and sports injuries.
Athletic Injuries ; Brain ; Brain Injuries ; Dentition ; Displacement (Psychology) ; Female ; Head ; Humans ; Mandible ; Maxilla ; Mouth ; Mouth Protectors ; Skull ; Tooth

OBJECTIVEFunctional magnetic resonance imaging (fMRI) was used to detect the cerebral cortical somatotopy during maximum voluntary clenching with and without soft splint in patients with hemimasticatory spasms (HMS) and the central mechanisms of HMS and the rule of the splint therapy.

METHODSFour HMS patients were selected and the spasms sides were right in two cases and left in the other two cases. FMRI images were obtained on Elscint/GE 2.0 Tesla MR system. Block design was used and the movement pattern was the onset of spasms after maximum voluntary clenching with and without soft splint. The fMRI data were analyzed by SPM99 software.

RESULTSWith the onset of spasms after maximum voluntary clenching, the activation of motor cortex in 3 HMS patients was found lateral dominance on the left side, and the other one showed bilateral activation. All the 4 patients were found activation in cingulate area. With the onset of spasms after maximum clenching wearing soft splints, the activation of motor cortex showed no lateral dominance on the left side, and 3 patients were not found activation in cingulate area.

CONCLUSIONSThe changes of the activation in motor cortex and cingulate area during the onset of spasms after clenching with and without soft splint might be the central mechanisms of the rule of splint therapy, through which the soft splint might function in alleviating muscle pain.

Brain ; physiopathology ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Masticatory Muscles ; pathology ; physiopathology ; Middle Aged ; Motor Cortex ; physiopathology ; Mouth Protectors ; Muscle Spasticity ; pathology ; physiopathology

PURPOSE: The purpose of this study was to estimate the effects of occlusal stability to identify action mechanisms of mouthguards, known to have a modulatory effect on limb muscle function. MATERIALS AND METHODS: This study included 20 male subjects to perform the isokinetic muscle tests and the Wingate anaerobic power test on both knee joints under five closed-mouth conditions: without or with 4 types of mouthguards with thickness of 2 mm based on premolar area: (1) full-coverage, (2) anterior partial-coverage, (3) right posterior partial-coverage, and (4) left posterior partial-coverage. The obtained results were subjected to One-way ANOVA with repeated measures, followed by post hoc test of the contrast method (alpha=.05). RESULTS: There was no significant difference between the closed position with and without a full-coverage mouthguard in all variables. However, significant differences were observed between with and without a partial-coverage mouthguard in muscular endurance during extension of the left knee, muscular power and endurance during flexion of the right knee. Additionally, significant differences were found between occlusal states with full- and partial-coverage mouthguards in muscular power and endurance during extension of the left knee. CONCLUSION: These findings indicate the elevation of vertical dimension by 2 mm or the inducement of occlusal stability had little effect on isokinetic muscle strength and anaerobic performance, while uneven distribution of occlusal force might have some positive effects.
Athletic Performance ; Bicuspid ; Bite Force ; Extremities ; Humans ; Knee ; Knee Joint ; Male ; Methods ; Mouth Protectors ; Muscle Strength ; Muscles ; Occlusal Adjustment ; Vertical Dimension