Cervical posture analysis in dental students and its correlation with temporomandibular disorder

The effect of temporomandibular joint dysfunction on the craniocervical mandibular system: A retrospective study

BACKGROUND

Temporomandibular disorders are the most common condition affecting the orofacial region, resulting in pain and dysfunction.

OBJECTIVE

This study aimed to elucidate the ambiguous association between cervical features and temporomandibular disorders by measuring the rotations between the skull-atlas, atlas-axis and mandible-atlas and examining the relationship between these rotations and temporomandibular disorders.

METHODS

Cone-beam computed tomography (CBCT) images from 176 patients, 97 females and 79 males with an average age of 25.7 years were used in this study. The patients were divided into two groups: those with joint dysfunction (n = 88) and those without (n = 88). The study employed various methods to determine rotations in the skull-atlas, atlas-axis and mandible atlas based on anatomical landmarks and measurements. These methods include the use of specific planes, angles and distances to identify and measure rotation. Data analysis was performed using the TURCOSA statistical software (Turcosa Analytics Ltd Co, Turkey, www.turcosa.com.tr).

RESULTS

The results showed that the degree of rotation between the skull and the atlas was higher in the TMD group than in the control group (p < .001). Similarly, Atlas-axis rotation was significantly higher in the TMD group (p < .001). However, no significant difference was found between mandible atlas rotations in the two groups (p = .546). The study also found a significant difference between the direction of rotation between the atlas and axis and the direction of mandible atlas rotation (p < .001) as well as between skull and atlas rotations and mandible-atlas rotations (p < .001).

CONCLUSION

Overall, the study suggests that there is a relationship between the skeletal structures of the cranio-cervico-mandibular system and TMD. Skull-atlas and atlas-axis rotations may play an important role in the aetiology of TMD in individuals with TMD. Therefore, it is important to evaluate rotations in the skull-atlas-axis region for the treatment of TMD.

Relationship of temporomandibular joint disorders with cervical posture and hyoid bone position

OBJECTIVE

To evaluate craniocervical posture and hyoid bone position in patients with and without temporomandibular joint disorder (TMD).

METHODS

A total of 113 people were included in the study, including 55 TMD patients and 58 healthy controls. Using lateral cephalograms, the craniofacial, craniocervical, and hyoid bone positions of the participants were evaluated in terms of 27 variables.

RESULTS

There was no significant difference in craniocervical angles between participants with or without TMD. While the Hy-B, Hy-NSL, Hy-NL measurements and FMA (°), AFH (mm) measurements of participants with TMD were lower than the control group, the hyoid angle was greater than the control group.

CONCLUSION

These study findings provide evidence that TMD is not related to craniocervical posture but to the position of the hyoid bone and craniofacial morphology.

An investigation of biomechanics, muscle performance, and disability level of craniocervical region of individuals with temporomandibular disorder

OBJECTIVE

To investigate biomechanics, muscle performance, and disability of the craniocervical region in temporomandibular disorder (TMD) patients and compare them with controls.

METHODS

Craniocervical posture was evaluated using lateral photography and radiography. Range of motion, muscle performance, disability, and TMD severity were assessed using an inclinometer, Functional Strength Testing of Cervical Spine, Neck Disability Index, and Fonseca Anamnestic Index, respectively.

RESULTS

Compared to the control group, the TMD group demonstrated higher cervical flexion angle (p=0.005) and neck disability (p<0.001) as well as lower cervical extension (p=0.040), right cervical rotation (p=0.005), left cervical rotation (p<0.001), and tragus-C7-horizontal (p=0.048) angles, and reduced muscle performances (p≤0.001). Most patients had higher than normal craniocervical angle (p<0.001). Muscle performance in each cervical motion (p<0.005) and disability (p<0.001) were associated with TMD severity in the TMD group.

CONCLUSION

Biomechanics, muscle performance, and disability of craniocervical region were altered in the TMD group.

Effects of sustained natural apophyseal glides versus rocabado 6 × 6 program in subjects with cervicogenic headache

BACKGROUND

Cervicogenic headache is designated as the most common type of secondary headache that results from conditions affecting the neck's bony components, muscles, and intervertebral discs rather than the head itself.

OBJECTIVE

The purpose was to determine the effects of Sustained Natural Apophyseal Glides (SNAGs) versus the Rocabado 6 × 6 program in subjects with cervicogenic headaches.

METHODS

This study was a randomized clinical trial. The sample size was 38, and participants aged 20-60 years (mean age 40.22 ± 9.66) suffering from cervicogenic headaches were randomly allocated using the lottery method into two groups with 19 participants in each group. Assessment of subjects was done before starting treatment and by the end of the 8th week for all the variables. Outcome measures were the Neck Disability Index (NDI), 6-item Headache Impact Test (HIT-6), Flexion-Rotation test (FRT) to assess the rotation range of motion at the level of C1-C2 (goniometer) and the Numeric Pain Rating Scale (NPRS) for the intensity of pain. Data analysis was done by SPSS (IBM) 25. To check the normality of the data the Shapiro-Wilk test was used.

RESULTS

In the Shapiro-Wilk test p-value of all the testing variables i.e. NDI, HIT-6 score, FRT and NPRS was > 0.05, data was normally distributed and parametric tests were used. Group A showed a considerable improvement (p < 0.05) in all variables compared to Group B, while within-group analysis of both groups shows that all outcome measures show significant results (p < 0.05).

CONCLUSION

It was concluded that both SNAGs and Rocabado's 6 × 6 exercises were effective for the treatment of cervicogenic headache but the effects of headache SNAG were superior and produced more improvement in intensity of headache, disability, frequency of headache, duration of headache as compared to Rocabado 6 × 6 exercises.

TRIAL REGISTRATION NUMBER

This study was registered at ClinicalTrials.gov ID: NCT05865808 on date 19/05/2023.

Temporomandibular joint disorders in seronegative spondyloarthritis: what a rheumatologist needs to know?

Temporomandibular joint (TMJ) can be affected in the context of spondyloarthritis (SpA) with detrimental impact on individuals' quality of life. Intra-articular inflammation, synovitis, enthesitis, disc displacement and cervical vertebrae malalignment are some of the pathophysiological phenomena involved. Temporomandibular joint disorders (TMD) incidence appears to be higher in patients with ankylosing spondylitis and psoriatic arthritis, especially when clinical evaluation includes not only imaging but relevant history, TMJ examination and diagnostic criteria for TMD. The Visual Analogue Scale (VAS) pain score and Health Assessment Questionnaire Disability Index (HAQ) quality of life score could be useful tools. Panoramic radiographs and ultrasound can be used for screening but in symptomatic patients magnetic resonance imaging (MRI) is preferable. Conservative management and early pharmacological treatment can prevent permanent joint impairment. For refractory cases, early referral to Legislation for Oral and Maxillofacial Surgery (OMFS) specialists is indicated. The aim of this narrative review is to address the involvement of TMJ in SpA and to encourage clinicians to incorporate TMJ assessment in their physical examination and basic screening.

Prevalence of impaired upper extremity neural mobility among smart device users during the COVID-19 pandemic

BACKGROUND

Both the development of various countries and people's health were impacted by the unforeseen global COVID-19 outbreak. Many countries prefer to do their daily business online. Although it was incredibly useful at the time, it still had a problem that was not properly addressed, especially among the student population.

OBJECTIVE

The objective of this study was to examine the prevalence of upper extremity neural mobility among students who were using smart devices during the COVID-19 pandemic.

METHODS

458 students who had previously taken home-based online classes during the COVID-19 pandemic and used a smart device for more than six hours were included in this study. The study was conducted in three phases. After being examined in the first two stages of the study, a total of 72 people were chosen for the final phase. Peripheral nerve mobility tests were performed on these 72 subjects.

RESULTS

This study observed that 15.72% of smart device users have been affected by forward neck posture and impaired peripheral nerve mobility in the cervical spine.

CONCLUSION

The study concludes that forward neck posture is associated with impaired peripheral nerve mobility among smart device users who were in home-based online classes during the COVID-19 pandemic lockdown. Hence, we suggest an appropriate treatment strategy focusing on preventing the forward neck posture through timely analysis and self-care therapies.

Genetic polymorphisms of TNF-α, IL-6, and IL-10 in female elderly patients with chronic temporomandibular disorder pain

AIM

To verify the association of the TNF-α, IL-6, and IL-10 polymorphisms with chronic temporomandibular disorder pain development in female elderly patients.

METHODS

Participants were evaluated according to Diagnostic Criteria for Temporomandibular Disorders. The genomic DNA was extracted from blood according to the Salting Out method followed by a quantification using the NanoDrop spectrophotometer. The -308G/A TNF-α polymorphism analysis was performed by the polymerase chain reaction-restriction fragment length polymorphism technique, the determination of -174G/C IL-6 polymorphism was performed by polymerase chain reaction, and the evaluation of the -1082A/G IL-10 polymorphism was carried out by polymerase chain reaction- allele-specific amplification. Data were analyzed using the BioEstat 5.3 software.

RESULTS

The -308G/A TNF-α polymorphism showed a significant difference when genotypes of cases with chronic temporomandibular disorder pain and controls were compared (p = .025). There was a lack of association regarding the -174G/C IL-6 polymorphism (p = .286) however, a positive association between the -1082A/G IL-10 polymorphism with chronic temporomandibular disorder was observed (p = .020).

CONCLUSION

The analyzed data of elderly subjects support the possible involvement of the GA genotype of the -308G/A TNF-α and the AA genotype of the -1082A/G IL-10 polymorphisms in the pathogenesis of chronic temporomandibular disorder pain.

Improvement of cervical spine mobility and stance stability by wearing a custom-made mandibular splint in male recreational athletes

OBJECTIVES

The range of motion (ROM) of the cervical spine and postural stability are important for an economical and motorically adequate adaptation of the body to any situation. Therefore, this study aims to analyze whether these two components of postural and movement control can be influenced by means of a splint in a centric position compared to habitual occlusion.

METHODS

38 recreational male athletes volunteered. Cervical spine ROM was recorded using an ultrasound system and the a pressure measuring plate for postural stability (length of center of pressure (CoP) movement, area of CoP). The two dental occlusion conditions employed were the habitual occlusion and wearing a splint in an idealized, condylar position close to the centric position. Level of significance was set at ρ ≤ 0.05.

RESULTS

The cervical spine mobility increased significantly by wearing the splint regarding rotation to the left (+3.9%) and right (+2.7%) and lateral flexion to the left (+4.4%) and right (+6.7%). Wearing the splint reduced the area of sway deflections by about 31.5% in the bipedal stance and by about 2.4% (left) and 28.2% (right) in the unipedal stance. The CoP trace was reduced in the sagittal plane by approximately 8.2% in the right single-leg stance.

CONCLUSIONS

The major findings seem to demonstrate that wearing a splint that keeps the jaw close to the centric relation may increase the cervical ROM and may improve balance stability in male recreational athletes. Changing the jaw relation in athletes can possibly aid the release of performance potentials by improving coordination skills.

Position of the Hyoid Bone and Dimension of Nasopharynx and Oropharynx after Occlusal Splint Therapy and Physiotherapy in Patients Diagnosed with Temporomandibular Disorders

Background: The aim of the study was to assess the position of the hyoid bone, as well as the width of the nasopharynx and oropharynx after occlusal splint therapy combined with physiotherapy in patients diagnosed with temporomandibular disorders (TMD). Methods: This was a clinical trial study. The study group consisted of 40 patients diagnosed with TMD, who were qualified for the treatment combining physiotherapy and occlusal splint therapy. Hyoid bone position as well as the width of the nasopharynx and oropharynx were assessed in lateral cephalograms taken before and after the end of the treatment. There were 15 generally healthy participants included into the control group, who had taken lateral cephalograms twice within the period of 1 to 2 years and did not receive any occlusal treatment in the meantime. Results: The position of the hyoid bone was significantly lowered and the dimension of the lower part of the oropharynx was significantly decreased after the end of the long-term occlusal splint therapy combined with physiotherapy in patients diagnosed with TMD. Conclusions: Long-term occlusal splint therapy combined with physiotherapy affected the position of the hyoid bone and the dimension of the lower part of the oropharynx.

Temporomandibular Joint Disk Displacements in Class II Malocclusion and Cervical Spine Alterations: Systematic Review and Report of a Hypodivergent Case with MRI Bone and Soft Tissue Changes

(1) Background: This study aimed to perform a literature review related to disk displacement (DD) in class II malocclusion or cervical vertebrae position alterations and to report a hypodivergent case with cervical pain and right anterolateral DD with reduction, left anterolateral DD with reduction, and left joint effusion. (2) Methods: A structured electronic search was conducted between March 2022 and April 2022, without time limits, following PRISMA guidelines, in the following databases: PubMed, Scopus, Embase and Cochrane; the terms “disc displacement”, “disk displacement”, “temporomandibular joint”, “class II malocclusion” and “cervical vertebrae” are searched. (3) Results: the following thirteen publications are included in this review: two prospective studies and eleven cross-sectional studies; for evaluating disk position, eight included publications used magnetic resonance imaging (MRI), whilst six studies used lateral cephalogram to determine craniofacial morphology and relationships between the cranial base, vertical skeletal pattern, maxilla and mandible. (4) Conclusions: although the literature still shows contradictory opinions, a relationship between temporomandibular disorders and cervical posture has been shown in the presented case as well as in the literature review.

Do Specific Craniomaxillofacial Features Correlate with Psychological Distress in Adult Pretreatment Orthodontic Patients? A Cephalometric Study

Purpose

To explore the relationship between craniomaxillofacial features and psychological distress among adult pretreatment orthodontic patients.

Methods

A group of 190 patients (95 males and 95 females) was included. Questionnaires including the Kessler psychological distress scale (K10) were sent to patients, and cephalograms were collected. Patients were divided into two groups according to K10 score: psychological distress group (score ≥ 20) and no psychological distress group (score < 20). Nineteen hard tissue and thirteen soft tissue parameters were traced on cephalograms to characterize the craniomaxillofacial features.

Results

There was no significant difference in gender or age distribution between the two groups. Male patients with psychological distress showed statistically significantly larger anterior facial height (AFH) (126.62 mm vs. 120.97 mm), upper lip length (25.11 mm vs. 23.26 mm), and smaller overbite (1.21 mm vs. 2.75 mm) than patients without psychological distress. Male patients with hyperdivergent pattern and open bite were more likely to have psychological distress. None of the parameters showed statistical differences across groups in females. Frankfort-mandibular plane angle (r = 0.235), Bjork's sum (r = 0.311), AFH (r = 0.322), overbite (r = −0.238), AFH/posterior facial height (r = 0.251), and upper anterior facial height (UAFH)/lower anterior facial height (LAFH) (r = −0.230) were correlated with K10 score in males. After adjusting gender and age, the AFH (B = 0.147) and UAFH/LAFH (B = −14.923) were significantly related with the K10 score.

Conclusion

Psychological distress was mainly correlated with hyperdivergent pattern, open bite, and larger lower anterior facial height proportion in pretreatment orthodontic patients. Orthodontists should be aware of the possible underlying psychological distress in patients with specific craniomaxillofacial features. Clinical assessment of psychological distress may need to take into account gender differences in patients.

Relationship between cervical angle and temporomandibular disorders in young and middle-aged population

OBJECTIVE

To verify temporomandibular disorders (TMDs) and cervical angles in a young and middle-aged population.

METHODS

Ninety participants were included, 45 of whom had TMDs. The participants were diagnosed according to the Research Diagnostic Criteria for TMDs. Lateral cervical radiographs were taken, and relevant cervical angles were measured. The general characteristics of the TMD group and control group were analyzed using chi-square analysis, and the relationship between cervical angles and TMDs was evaluated using the unpaired t-test.

RESULTS

The decrease in C2-C7 Cobb and increase in the posterior occipitocervical angle (POCA) were associated with the incidence of TMDs (p < 0.0001).

CONCLUSION

This study revealed that the cervical angle was related to TMDs. People with a long-time habit of head bending posture had a decrease in C2-C7 Cobb and an increase in the POCA. This group of people was more likely to develop TMDs.

TNF-α levels and presence of SNP-308G/A of TNF-α gene in temporomandibular disorder patients

INTRODUCTION

Temporomandibular disorder (TMD) refers to a group of conditions that compromise the harmonious movement and function of the temporomandibular joint, masticatory muscles, and associated structures. The etiopathogenesis of TMD is multifactorial but not well-understood, with the role of genetic factors still being unclear.

OBJECTIVE

This review aims to summarize the results of studies that evaluated TNF-α levels and the -308G/A TNF-α polymorphism in TMD patients. This study emphasizes the importance of a more selective treatment involving TNF-α inhibitors that can potentially reduce inflammation and pain, and improve quality of life.

METHODS

The MEDLINE/PubMed database, Cochrane Library, and Web of Science database were searched for case-control studies published until September 2020 that compared levels of TNF-α or presence of its -308G/A polymorphism in TMD patients and healthy individuals.

RESULTS

Six case-control studies were identified with a total of 398 TMD patients, aged between 12 and 78 years. The control group consisted of 149 subjects, aged between 18 and 47 years. The occurrence of TMD was predominant in females. Majority of studies found high TNF-α levels in TMD patients, compared to the control group. One of these studies found a positive correlation between the GA genotype and the development of TMD.

CONCLUSION

Majority of the TMD patients showed elevated TNF-α levels, and a possible explanation for this could be the presence of the -308G/A polymorphism.

Hyoid Bone Position in Patients with and without Temporomandibular Joint Osteoarthrosis: A Cone-Beam Computed Tomography and Cephalometric Analysis

Objective

To assess the differences in hyoid bone position in patients with and without temporomandibular joint osteoarthrosis (TMJOA).

Methods

The present cross-sectional study was conducted in 427 participants whose osseous status was evaluated using cone-beam computed tomography and classified into normal, indeterminate osteoarthrosis (OA), and OA. The hyoid bone position and craniofacial characteristics were evaluated using cephalograms. Patients were divided into the normal group (N = 89), indeterminate OA group (N = 182), and OA group (N = 156). Descriptive statistics, one-way analysis of variance, and age- and sex-based stratified analyses were performed. P < 0.05 was considered statistically significant.

Results

The differences in Hy to MP, Hy-RGn, Hy to C3-RGn, C3-RGn, and Go-Hy-Me among the three groups were statistically significant. The differences in the Frankfort-mandibular plane angle, saddle angle, articular angle, gonial angle, ramus height, and posterior facial height were statistically significant. After adjusting age and sex, the Hy-RGn and C3-RGn in the normal group were significantly greater than the OA group. No statistical differences were observed in the hyoid measurements in the stratified analyses in males or subjects less than 18 years old. The differences in Hy to MP, Hy to C3-RGn, and Go-Hy-Me in female patients among the three groups were statistically significant. The differences in Hy to SN, Hy to FH, Hy to PP, Hy to MP, Hy-RGn, Hy-C3, Hy to C3-RGn, Go-Hy-Me, Hy-S, and C3-Hy-S in adults were statistically significant.

Conclusion

The differences in the hyoid bone position, mainly relative to the mandible, were statistically significant in patients with or without TMJOA. The difference pattern varied among different age and sex groups. Clinical evaluation of the hyoid position must consider the age and sex of patients. Longitudinal studies are required to clarify the causal relationship between TMJOA and hyoid bone position.

Association of cervical spine signs and symptoms with temporomandibular disorders in adults: a systematic review protocol

OBJECTIVE

The objective of this systematic review is to assess the evidence of association of cervical spine signs and symptoms with temporomandibular disorders (TMD). This will help to lend credence to mechanisms supporting the association in order to improve care strategies for this condition.

INTRODUCTION

The association of cervical spine impairments (in relation to neck posture, cervical spine mobility, muscle tenderness, muscle activity, and neck disability) with TMD has been widely discussed in the literature. Clarification of this relationship is important for health professionals to better assess and treat TMD.

INCLUSION CRITERIA

Eligible studies will include participants aged 18 years and over, with a diagnosis of TMD from the Research and Diagnostic Criteria for Temporomandibular Disorders or a revised version. Exclusion criteria will be participants with previous temporomandibular joint surgery, history of trauma or fracture in the temporomandibular joint or the craniomandibular system; serious comorbid conditions such as cancer, rheumatic disease, and neurological problems; primary cervical spine disorders such as disc herniation or spinal degenerative changes; or systemic disease such as ankylosing spondylitis.

METHODS

The search for articles will be conducted in the databases PubMed, PEDro, CINAHL, Web of Science, and Embase, without language or time restrictions. Two independent reviewers will review the title, abstract, and full texts of identified studies; select studies against the inclusion criteria; assess the methodological quality of eligible studies using critical appraisal tools; and perform data extraction. Relevant quantitative data will be pooled with statistical meta-analysis, when possible.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42019123698.

Systematic changes of the static upper body posture with a symmetric occlusion condition

Background

Temporary occlusal changes and their influence on the upper body statics are still controversially discussed. Furthermore, concrete statements on whether age- or gender-specific differences in neurophysiological reactions exist are missing. Therefore, it is the aim of this study to evaluate the immediate effects of a symmetrical occlusion blocking on the upper body posture. These effects shall be investigated for both genders and for a larger age range.

Methods

In this study, 800 (407f/393 m) subjects volunteered aged from 21 to 60 years. Both genders were divided into four age groups according to decades. The three-dimensional upper body posture was measured by using the rasterstereography (ABW-Bodymapper). The habitual static posture was measured in two dental occlusion conditions (a) in rest position and (b) symmetrical blocking in the bicuspid region by cotton rolls.

Results

A significant reduction of the trunk length (0.72 mm; p <  0.001), an increase of the lumbar (0.30°; p <  0.001) and the thoracic bending angle (0.14°; p = 0.001), a reduction of the spinal forward decline (0.16°; p <  0.001) and a reduction of the scapular distance (0.36 mm; p = 0.001) was found. Gender-specific reactions can only be recorded in scapular distance, in that regard men reduce this distance while over all age groups women did not show a significant change.

Discussion

Slight gender- and age-independent reactions due to a symmetric occlusion blockade are shown: A gender independent reaction of the spinal related variables in the sagittal plane (thoracic and lumbar flexion angle, trunk length, spinal forward decline). In addition, a gender specific change of the shoulder blade distance could be observed, where men reduced the distance while female did not show a change. However, since these reactions are of a minimum amount, it can be concluded that neurophysiological compensation mechanisms work equally well regardless of age and sex, and the upper body posture of healthy people changes only very slightly due to a temporarily symmetrical altered bite position.

Temporomandibular disorders in ankylosing spondylitis: a cross-sectional, monocentric study

There are contradictory results in the relevant literature about the relationship between objective determinants of craniocervical posture and temporomandibular disorder (TMD), whereas no study has worked on ankylosing spondylitis (AS) and TMD relationship. We conducted this study to test the predictors of TMD in AS patients and its relationship with craniocervical posture. AS patients aged between 18 and 50 years consecutively admitted to our outpatient clinics were recruited. TMD was diagnosed by 'Diagnostic Criteria for Temporomandibular Disorders (DC/TMD)'. Spinal mobility was assessed by BASMI; disease activity by ASDAS-CRP and neck disability by Neck Disability Index. Craniocervical posture was assessed on lateral cervical X-ray by measuring the craniocervical angle, cervical curvature angle, suboccipital distance, atlas-axis distance, and anterior translation distance. A total of 98 (58.2% female) patients with a mean age of 37.4 ± 8.2 years were enrolled in this study. TMD was diagnosed in 58 (59.2%) patients. Spinal mobility and craniocervical posture measurements were similar among the two groups. Smoking, bruxism (in females), neck disability and AS disease activity (in males) were higher in TMD patients. Multivariate analysis revealed active smoking (aOR 6.9; 95% CI 1.8-25.6; p = 0.004), bruxism in females (aOR 17.9; 95% CI 2.0-159.2; p = 0.01), high ASDAS in males (aOR 11.8; 95% CI 1.2-122.5; p = 0.038) and neck disability (aOR 12.7; 95% CI 3.8-42.9; p < 0.001) as independent risk factors for TMD in AS patients. No relationship between the craniocervical posture measurements and TMD was found in AS patients. Active smoking, high disease activity in males, bruxism in females and neck disability were found as predictors of TMD in AS patients.

Cervical spine range of motion, posture and electromyographic activity of masticatory muscles in temporomandibular disorders

Abstract Introduction: Temporomandibular joint disorders (TMD or TMJD) involve clinical problems and symptoms affecting the temporomandibular joint (TMJ) and associated structures. The temporomandibular joints are anatomically connected to the cervical region, where cervical spine movements occur simultaneously to masticatory muscle activation and jaw movements. Objective: Our study sought to assess the relationship between the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), surface electromyography (sEMG) of the masticatory muscles, posture and cervical flexibility in women with TMD. Method: Fifty women with an average age of 27.0 ± 6.37 years, diagnosed with TMD according to RDC/TMD, were assessed for craniocervical posture, cervical flexibility and sEMG of the masticatory muscles. Results: There were no differences in jaw function limitations, depression, pain level and its interference in work ability and daily activities, posture and sEMG between TMD diagnoses or between muscle classification (p > 0.05). Depression scores were higher among participants with biarticular dysfunction (p = 0.023). The group with bruxism exhibited a higher pain level at assessment (p = 0.001) and a greater reduction in work ability (p = 0.039). Subjects with muscular and mixed TMD showed less cervical rotation to the right when compared with those with articular TMD. Conclusion: There was no difference in posture or sEMG values for TMD diagnoses, joint and muscle dysfunctions and the presence of bruxism. Muscle dysfunction is associated with reduced cervical rotation to the right. Jaw function limitations did not interfere in posture or sEMG and depression was associated with pain.

The inconclusiveness of research on functional pathologies of the temporomandibular system and body posture: Paths followed, paths ahead: A critical review

Objective: Literature on the functional pathologies of the temporomandibular system (FPTS) in its relationships with body posture is plagued with inconclusiveness. Despite being sometimes altogether disregarded, the issue is most relevant, due to its clinical implications. This paper aims for a deeper understanding of the origins of the inconclusiveness of research on such relationships by means of a critical analysis of the scientific literature on the subject, in order that clinicians may better treat patients with FPTS.Methods: Analysis of over 100 studies, published from 1918 through March 2018 in the PubMed database, using descriptors temporomandibular joint disorders and posture.Results: The analysis of the paths followed by researchers allowed for pinning down several methodological issues that may have led to the prevailing ambiguity on the matter.Conclusion: This review then proposes certain standardization of procedures in future studies, to be conducted by a proposed consortium of researchers.

Relationship between anxiety and temporomandibular disorders in dental students

OBJECTIVE

To evaluate the prevalence of temporomandibular disorder (TMD) in dental students and its correlation with anxiety.

METHODS

After probability sampling, 105 students were selected. The diagnosis of TMD was carried out using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) - Axis I; the anxiety level was obtained by the State-Trait Anxiety Inventory (STAI). Data from TMD and anxiety were calculated through frequency and Chi-square test to assess the association between TMD and anxiety, considering a significance level of 5%.

RESULTS

TMD was present in 36.2% of the students; disc displacement (42.1%), and arthralgia (42.1%) were the most prevalent subtypes. The majority of students presented both traits (57.1%) and state (65.7%) anxiety in mild levels, followed by moderate levels. No statistical association between TMD and anxiety was found (p > 0.05).

CONCLUSION

Joint TMD was the most prevalent subtype of TMD in dental students and was not associated with anxiety levels.