the literature suggests that there is a correlation between the stomatognathic system and 
 the musculoskeletal system .
indeed , it seems certain that an alteration of the 
 tooth - mandible - tongue complex affects postural attitude1 .
it has been reported that proprioception and postural control are 
 of great importance for optimal sports injury prevention2,3,4,5 . in this context , lee et al . 
 confirmed that an exercise program aiming to improve proprioception can positively influence 
 the balance ability of stroke patients6 . 

tecco et al . reported a change in the postural stability of subjects with knee pathologies . 

these pathologies can generate changes in the function of the masticatory muscles , neck and 
 trunk7 .
moreover , the mandible position 
 is determined by dental occlusion , the relative position of teeth to each other8 , 9 . in 
 addition
, some studies have found that the stomatognathic system and mandible disorders can 
 influence the spine10 , 11 .
tecco et al . also observed that the loading percentage 
 and the loading surface on the right and the left feet were influenced by an experimentally 
 induced imbalance of occlusion created by a cotton roll positioned in dental arches12 .
furthermore , it was observed that the 
 temporomandibular joint ( tmj ) affects other systems13 , 14 .
many of their patients 
 also had symptoms of cervical spine disorders and head , neck and shoulder pain14 .
investigated the postural stability of twenty - four 
 subjects , randomly assigned to an exercise or control group , who performed a craniocervical 
 flexion exercise four days per week for five weeks and reported their postural stability 
 increased15 .
moreover , bjrne in 2007 
 showed that muscular problems and tinnitus were reduced by injection of lidocaine into the 
 jaw muscle14 .
furthermore , some studies have reported that the stomatognathic 
 system affects physical performance , and that muscle activity is dependent on the position 
 of the tmj1 , 12 .
some studies have shown that the stomatognathic system could 
 elicit improvements in sport performances16 , 17 , but the hypothesis has not yet been 
 confirmed18 . in 2012 , baldini et al . 

reported there was an increase in the relative strength of the quadriceps muscles when a 
 patient wore an occlusal splintsplint19 . 

our interest has focused on the role of the mandible position in physical performance , and 
 the aim of this pilot study was to examine the influence of the temporomandibular joint and 
 dental occlusion on the explosive strength of football players .
this study was performed in compliance with the 
 declaration of helsinki , and the principles of the italian data protection act ( 196/2003 ) 
 were observed .
the athletes selected for this study were 60 male football player volunteers . 
 the squat jump ( sj ) was the evaluation test adopted and all participants attempts were properly 
 randomized ( n 30 with mo vs. mc ; n 30 mc vs. mo ) .
the sj execution was standardized with a joint angle at departure 
 of 90 degrees .
the protocol established for 
 the execution of the jumps was as follows . in a warm - up phase of 10 minutes , the athletes 
 performed light running ( < 65% vo2max ) and stretching exercises ( four times 6 
 static postures for 20 seconds each ) , then each individual performed three practice sjs with 
 the mouth closed ( mc ) , and mouth open ( mo ) .
then the athletes climbed on the platform for 
 measurement and proceeded to perform sjs under the two different occlusal conditions .
the 
 participants were given a 2 minutes rest period between trials , and sj was performed without 
 shoes .
the values were recorded using the freemed system and a force platform ( sensor 
 medica ; guidonia montecelio , roma ) .
all data were input to an excel file and the best performance of both occlusal conditions 
 was selected for comparison .
sixty subjects were enrolled in this study ( age : 24  7.0 yrs ; height : 174  4.6  cm ; weight 
 63.7  7.6  kg ) .
the best performances recorded were 38.50  4.001  cm with mc and 40.41  
 4.093  cm with mo .
the statistical analysis showed there was a statistically significant 
 difference between the performances ( p < 0.0001 ) .
the mouth open condition resulted in 
 improvement in the vertical jump height compared to the mouth closed condition .
some studies have found that there is a correlation between the stomatognathic system and 
 the musculoskeletal system , and that an alteration of the tooth - mandible - tongue complex 
 seems to affect postural attitude1 , 11 . however , the conclusions of the different 
 studies are not unanimous .
many studies are found in the literature , but despite the high 
 number of articles published , the mechanism through which orthodontic treatment influences 
 the etiology of tmj dysfunction is still unknown24 . in the present pilot study , we sought to investigate whether the 
 position of the mandible affects the explosive force .
our results are certainly encouraging 
 but , according to the scientific literature , it is conceivable that the protagonist of the 
 change is the trigeminal nerve25,26,27 . 

numerous anatomical associations have been described between the trigeminal system and the 
 nervous structures implicated in posture control .
the mesencephalic nucleus of the 
 trigeminal nerve is a sensorial nucleus with unique characteristics28 .
their results demonstrated the effects of trigeminal 
 afferences on postural stabilization29 : 
 postural deviation under the eyes closed condition was observed after unilateral truncular 
 anaesthesia of the mandibular nerve in static posturography29 .
another item of interest is the relationship between the trigeminal 
 nerve and the muscle - fascial chain .
the fascial system is important not only because it can 
 passively distribute tension in the body muscles when mechanically stimulated , but also 
 because it contains mechanoreceptors and possesses an autonomous contractile ability that 
 influences the tension of the fasciae .
the stomatognathic alignment exercise program was performed by an 
 experimental group and consisted of mobility exercises for the tmj and neck , and postural 
 correction . at the end of the study
, all the parameters of neck mobility and mouth opening 
 had significantly improved . in conclusion ,
the result of this pilot investigation suggests 
 that the mandible position influences physical performance , and that this could have 
 practical applications in sports and exercise sciences .
these conclusions need to be 
 supported by further studies with different cohorts and larger populations .
 [ purpose ] recent findings suggest there is an interesting interaction between the 
 stomatognathic system and the musculoskeletal system . 
 the aim of this study was therefore 
 to examine the influence of the temporomandibular joint on the explosive strength of the 
 lower limbs . 
 [ subjects and methods ] an observational study was carried out . 
 the subjects 
 were 60 male football players who voluntarily participated in the investigation . 
 after a 
 warm - up phase of 10 minutes , each participant performed three squat jumps ( sj ) with 
 different mandible positions : mouth closed and mouth open . 
 sj heights were recorded using 
 a sensor medica force platform and the freemed system . 
 [ results ] sixty participants were 
 enrolled in this study ( age : 24  7 yrs ; height : 174  4.6  cm ; weight 63.7  7.6  kg ) . 
 the 
 sj heights with the mouth closed , 38.50  4.0  cm , were shorter than those with the mouth 
 open , 40.4  4.1  cm . 
 statistical analysis showed there was a statistically significant 
 difference between the performances . 
 [ conclusion ] this pilot study highlighted that 
 occlusal factors can influence physical performance and this could have practical 
 applications in sports and exercise science . 
 however , our results have to be confirmed in 
 studies with larger numbers of participants and supported by other investigations . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION