the temporomandibular joint ( tmj ) is the most regularly used joint in the human body .
it 
         opens and closes about 1500 to 2000 times a day and is instrumental in several functional 
         movements such as chewing , breathing and pronunciation.1 because the tmj is a very regularly used joint , its bone , 
         muscle or cartilage may deteriorate over time , leading to disorders of the tmj . 
        
temporomandibular disorder ( tmd ) may lead to adaptations in certain body structures to 
         minimize a patient s pain or discomfort , and also to reconfigure musculoskeletal 
         stress zones .
these adaptations often lead to deviations in normal body posture , which 
         includes changes in the longitudinal plantar arches.2 epidemiological studies of tmd show that 5 to 6% of the world population will suffer a 
         painful experience involving the tmj at some point during their life,3 and that around 8.5 million brazilians will require some kind 
         of intervention for tmd.4 the biomechanical complexity of body posture derives from the functional integration of 
         several body segments : when there is a change in any biomechanical subunit , a refinement of 
         the postural control systems will necessarily occur.5,6 the muscle 
         groups of the stomatognathic system belong to the cervical muscular chain . considering that 
         the musculoskeletal system is composed of several such muscular chains that are integrated 
         with one another , any disturbance of a body segment will lead to a reorganization of other 
           segments.7,8 this fine tuning of posture control leads to body segment 
         adaptation and realignment , whether physically near to or distant from the tmj.2,5,8,9 deviations in the lower limbs can interfere with postural 
         organization and may even impact head and neck posture.7 valentino et al.10 have shown that the 
         simulation of a flat foot results in increased muscular activity of the masseter and 
         temporal muscles . when a concave foot was simulated , this activity reduced .
alteration of 
         the longitudinal plantar arches stimulates mechanoreceptor neurons , and this readjusts head 
         position and body center of gravity .
these data reinforce the theory that a deviation in one 
         joint unit can lead to compensation in other joints and , therefore , to an alteration of 
         whole - body posture.2,59 it is important to establish a clear relationship between poorly aligned body posture and 
         the incidence of tmd in order to clarify if the best physical therapy treatment for tmd 
         patients should include body posture realignment .
our goal is to minimize symptomatology and 
         to de - emphasize postural deviations that may lead to bone and muscle system imbalance.9 , 1114 although there exist certain studies1518 that have 
         attempted to find a relationship between postural alterations in tmd patients , these studies 
         did not select patients according to their specific diagnoses .
furthermore , to date , there 
         have been no studies that investigate this relationship in a group of tmd patients composed 
         only of women diagnosed with anterior disc displacement .
also , body deviation studies have 
         focused only on the upper quarter of the body and have not investigated foot alignment . in 
         one study10 that involved the foot , 
         postural deviation was only simulated .
consequently , the researchers did not adequately 
         represent real - world postural foot deviations , and the presence of head and neck postural 
         problems was not assessed . in the same way
, other studies3,11 did not 
         investigate pain in parts of the body other than in the upper quarter .
the aim of this paper was to evaluate and describe the most common tmd diagnosed at the 
         occlusion and tmj service ( soa ) of the faculty of dentistry of the university of 
         so paulo ( fousp )  anterior disc displacement  and the 
         associated postural deviations as they relate to the plantar arches , lower limbs , shoulder 
         and pelvic girdle , vertebral spine , head and mandibles .
we also aimed to identify common 
         signs and symptoms across the entire body , through our observations of a group of women 
         between 20 and 30 years of age , all of whom had been diagnosed with anterior disc 
         displacement .
our study involved 26 volunteer women distributed across two groups : a disc displacement 
         group ( ddg ) and a control group ( cg ) .
the choice of involved subjects was based on 
         epidemiological research that showed women from 15 to 40 years of age are most often 
         affected by tmd.1920 the control group consisted of 16 female volunteers without a clinical diagnosis of disc 
         displacement , aged 24.4  2.8 yr and of body mass 56.2  7.9 kg . 
        
they were matched for age and weight with a disc displacement group , consisting of 10 female 
         patients 20 to 30 years of age ( 24.5  3.0 yr , 55.5  7.4 kg ) who 
         had been diagnosed with unilateral tmj disc displacement and had presented symptoms for 40.4 
          41.5 months prior to the start of our trial .
the patients 
         disorders were clinically diagnosed by postgraduate students from occlusion and tmj service 
         ( soa ) of faculty of dentistry of university of so paulo ( fousp ) .
exclusion criteria were : any trauma history , anatomical deformities and skeletal system 
         fractures , hormonal alterations , orthopedic or rheumatic diseases already diagnosed , three 
         months or more into pregnancy , and no previous tmd treatment over a period of 15 days before 
         this initial assessment .
all subjects were interviewed regarded their 
         parafunctional habits , signs and symptoms , and degree of pain consistent with the visual 
         analog scale . following this initial step , an experienced physical therapist performed an 
         independent postural body assessment by visually inspecting all the subjects . for this part 
         of the study ,
the patients were asked to stand as comfortably as possible wearing bathing 
         suits in a bipedal position with bilateral symmetric weight bearing , while looking towards 
         the horizon .
the physical therapist marked the following bone reference points using 
         adhesive tape : lateral malleoli , heads of the fibulas , major trochanter of the femur , 
         antero - superior and postero - superior iliac spines , coracoid processes , c7 and the inferior 
         angle of the scapulas .
the frontal anterior and posterior planes and sagittal right and left 
         planes were evaluated .
the evaluation protocol was based on kendall21 : any changes from the standard alignment posture were 
         considered evidence of postural deviations . following data acquisition , an experienced 
         physical therapist confirmed all postural classifications using digital photos .
this 
         analysis was performed using visual inspection with a digital matrix of horizontal and 
         vertical lines , all of which passed through the bone reference markers .
footprint 
         measurements were taken using a harris mat , and the characteristics of the longitudinal 
         plantar arches were evaluated according to cavanagh and rodgers.22 the cavanagh and rodgers22 plantar arch evaluation uses the ratio between the mid - foot 
         area and the total foot area , excluding the toe area , as measured by a digital planimeter . 
        
the arch is classified as follows : lower than 0.21 is considered elevated , between 0.22 and 
         0.26 is normal , and higher than 0.26 is designated a low arch .
data were analyzed using descriptive statistics and were tested to compare independent 
         group means .
when comparing dichotomic categorical data , we used the non - parametric 
         chi - squared and fisher s exact tests .
the disc displacement group showed reported pain more often , but only the presence of local 
         tmj pain was significantly different in comparison with the cg ( p = 0.006 ) 
           ( table 1 ) .
there were no statistical 
         differences between groups ( p>0.05 ) in parafunctional habits ( biting tongue , 
         cheeks or lips , chewing gum , biting objects such as pen caps , holding one s head 
         with the hands , chewing only on one side of the mouth ) .
the footprint measurements that characterized patients longitudinal plantar 
         arches were not different between groups ( p > 0.05 ) .
both 
         groups presented normal longitudinal plantar arches , according to cavanagh and rodgers18 ( cg = 56.25% , ddg = 50% ; low arch 
          cg = 18.75% , ddg = 20% ; high arch 
pelvis , head and spine - based postural assessments in the frontal and sagittal planes were 
         significantly different between the groups ( tables 2 and 3 ) . finally , the 
         postural assessment of the mandibles in the frontal plane showed a higher incidence of 
         deviation to the left side with an open mouth in the ddg ( 40% ) ( p = 0.03 ) 
           ( table 4 ) .
the main purpose of our study was to evaluate and associate the presence of anterior disc 
         displacement with postural deviations across the entire body .
the hypothesis of a functional 
         relationship between the stomatognathic system and other body regions remains controversial , 
         especially for body areas that are distant from the tmj.5,913 other studies have attempted to identify a relationship between postural alterations in tmd 
         patients , but none of these trials have specifically focused on women . besides , many studies 
         have only investigated the upper quarter of the body , either to assess postural alignment or 
         to identify pain locations .
our results demonstrated that important postural alterations are exhibited by subjects with 
         anterior disc displacement , and these postural deviations can be associated with tmd .
considering that pain levels were similar across both groups , except for local tmj pain 
         that was more frequently reported by the ddg subjects , we suggest that there exists no 
         relationship between body pain and tmd .
although parafunctional habits were more often present in the ddg , there were no 
         statistical differences between the groups .
consistent with previous studies4,23 , our data show the importance of carefully investigating the real influence of 
         parafunctional habits on tmd .
the evaluation of patients longitudinal plantar arches showed no statistically 
         significant difference between cg and ddg .
our results showed similarities in longitudinal 
         plantar arch anthropometry between the groups , suggesting no relationship between tmd and 
         this characteristic .
this result contrasts with that of another study10 in which flat foot simulation induced an increase in 
         temporal and masseter emg activity on the side of the simulation .
this could cause postural 
         deviations in cervical and head positions and problems at the tmj .
such a hypothesis 
         regarding the presence of head and neck postural deviations was not confirmed , and no 
         postural evaluations were conducted in that study .
postural assessments in our study confirmed the findings of previous studies1518 , which revealed ddg - related changes in body posture , 
         particularly in the pelvic position , lumbar and thoracic spines , head and mandibles .
these 
         deviations seem to confirm the relationship between the position of the tmj and other body 
         parts .
our results support the theory that a deviation in one joint subunit may lead to 
         compensations in other joints2,59 .however , these results must be interpreted with caution 
         because it is not possible to conclude whether tmd is a cause or a result of body posture 
         deviations .
first , the clinical diagnoses may 
         have included a limited number of false - positive disc displacement diagnoses.24,25 in addition , and because this was a transverse study , subjects were evaluated 
         only once , so the data do not take into account individual variation over time .
due to the high incidence of tmd across the population , investigating the relationship 
         between this condition and global posture is extremely important .
our data showed 
         significant ddg - related deviations in the pelvis , lumbar and thoracic spines , head and 
         mandibles .
although it is not possible to positively state a cause - effect relationship , our 
         data at least verify the mutual existence of global body posture deviations and tmd .
we conclude that the postural evaluation of tmd patients is clearly important as a global 
         approach to provide accurate prevention and treatment .
such evaluations can help physicians 
         to achieve more precise diagnoses and select the best possible functional rehabilitation 
         techniques . in the case of tmd patients
, it is essential to achieve a better level of 
         interaction among the different therapeutic subspecialties .
 

 aim : 
 to identify the relationship between anterior disc displacement and global posture 
             ( plantar arches , lower limbs , shoulder and pelvic girdle , vertebral spine , head and 
             mandibles ) . 
 common signs and symptoms of anterior disc displacement were also 
             identified . 


 
 introduction : 
 global posture deviations cause body adaptation and realignment , which may interfere 
             with the organization and function of the temporomandibular joint 
 . 


 methods 
 : global posture evaluation was performed in a group of 10 female patients ( 20 to 30 
             years of age ) with temporomandibular joint disc displacement and in a control group of 
             16 healthy female volunteers matched for age , weight and height . 
 anterior disc 
             displacement signs , symptoms and the presence of parafunctional habits were also 
             identified through interview . 


 
 results : 
 patients with disc displacement showed a higher incidence of pain in the 
             temporomandibular joint area , but there were no differences in parafunctional habits 
             between the groups . in the disc displacement group , postural deviations were found in 
             the pelvis ( posterior rotation ) , lumbar spine ( hyperlordosis ) , thoracic spine 
             ( rectification ) , head ( deviation to the right ) and mandibles ( deviation to the left with 
             open mouth ) . 
 there were no differences in the longitudinal plantar arches between the 
             groups . 


 
 conclusion : 
 our results suggest a close relationship between body posture and temporomandibular 
             disorder , though it is not possible to determine whether postural deviations are the 
             cause or the result of the disorder . 
 hence , postural evaluation could be an important 
             component in the overall approach to providing accurate prevention and treatment in the 
             management of patients with temporomandibular disorder . 

 
INTRODUCTION
METHODS
RESULTS
DISCUSSION
CONCLUSION