Influence of temporomandibular joint disc displacement on craniocervical posture and hyoid bone position

Impact of professional, recreational and nonsinging on temporomandibular disorders - a comparative study based on a self-assessment questionnaire

BACKGROUND

This study investigates the relationship between professional and recreational singing on temporomandibular disorders (TMDs) in women compared to a nonsinging control group.

METHODS

A total of 288 female subjects between the ages of 18 and 45 participated in the self-assessment questionnaire including demographic data, as well as questions on vocal practice and TMDs symptoms. Depending on the singing time per week, the (non)vocalists were assigned to the groups professional (n = 96), recreational (n = 96) and nonsingers (n = 96).

RESULTS

The TMDs prevalence in professional singers (42%) was higher than that in recreational singers (31%) and noticeably higher than that in nonsingers (25%). The Fisher-Freeman-Halton exact test showed that the differences between the groups were not noticeable (p = .053) but could be formulated as tendencies. The professionals suffered much more from restricted jaw movement (p = .004; OR = 2.718; 95% CI = 1.409-5.242), temporomandibular joint sounds (p < .009; OR = 2.267; 95% CI = 1.264-4.064) and temporomandibular pain (p = .010; OR = 2.333; 95% CI = 1.264-4.308) than nonsingers.

CONCLUSIONS

Singing might have an enhancing effect on the appearance of TMDs. In particular, professional singers suffered more from self-reported TMDs than recreational singers and nonsingers. In addition to the high level of physical workload if participating in professional singing, the psychosocial impact should be investigated more in further studies. No new treatment strategies resulted from this study, as the etiological significance of singing is still unclear. Knowledge about risk factors for multifactorial TMDs can help practitioners and patients prevent and treat TMDs.

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.

Correlation between craniocervical posture and upper airway dimension in patients with bilateral anterior disc displacement

OBJECTIVE

To investigate the relationship between upper airway dimension and craniocervical posture in adult patients with bilateral anterior disc displacement and to provide some references for clinical diagnosis and plan formulation in orthodontics.

METHODS

Based on RDC/TMD (Research Diagnostic Criteria for Temporomandibular Disorder), 98 Patients were divided into three groups by two experienced TMJ (Temporomandibular Joint) specialists: bilateral disc normal position group (BN), bilateral anterior disc displacement with reduction group (ADDWR) and bilateral anterior disc displacement without reduction group (ADDWoR). Inter-group comparison and correlation analysis were performed after 11 craniocervical posture and 15 upper airway dimension measurements finished with Dolphin and Uceph software in Two or Three-dimensional.

RESULTS

Anterior disc displacement often accompanied with extension of craniocervical posture, as ADDWR and ADDWoR groups have significantly higher cervical curvature and inclination than BN group (P < 0.05). Simultaneously anterior disc displacement often associated with constrained upper airway dimension for the total and each segment upper airway volume were significantly smaller in ADDWR and ADDWoR than BN group (P < 0.05). Correlation analysis revealed that C0-C1 (the distance from the base of the occipital bone (C0) to the posterior arch of the atlas (C1)) is significantly related to the total and each segment upper airway volume reduction (P < 0.05).

CONCLUSION

There exists markedly close correlation between anterior disc displacement and craniocervical posture forward extension, which may be physiologically adaptive cervical extension to keep oropharyngeal airway unobstructed as upper airway dimension constrained by anterior disc displacement.

CLINICAL RELEVANCE

These findings allow us to infer the potential consequences if the treatment of anterior disc displacement would result in an improvement of intervertebral relationships and upper airway constraint.

Correlation between temporomandibular joints and craniocervical posture in patients with bilateral anterial disc displacement

OBJECTIVE

To study the changes of temporomandibular joints and craniocervical posture in adult patients with bilateral anterior disc displacement, and to explore their correlation, which may provide some clinical value for clinical diagnosis and treatment planning.

METHODS

Ninety-eight adult patients were divided into 3 groups: 29 patients in bilateral disc normal position group (BN), 33 patients in bilateral Anterior Disc Displacement With Reduction group (ADDWR) and 36 patients in bilateral Anterior Disc Displacement Without Reduction group (ADDWoR). Dolphin and Uceph software were used to measure 14 items of temporomandibular joint and 11 items of craniocervical posture for comparison and correlation analysis between groups.

RESULTS

There were significant differences in bilateral joint space between three groups. Compared with the BN, the anteroposterior diameter of the condyle was significantly reduced, the condyle was significantly displaced posteriorly and superiorly in the ADDWR and ADDWoR, but the joint fossa width and joint fossa depth did not change significantly. Cervical curvature and inclination were greater in patients with anterior disc displacement than BN, indicating that the craniocervical posture of adult patients with anterior disc displacement was extended and protrusive.

CONCLUSION

Anterior disc displacement of the temporomandibular joint can displace the condyle upwards and posteriorly and reduce the anteroposterior diameter of condyle, and then make the condyle closer to the wall of articular fossa to induce joint symptoms. Additionally, craniocervical postural position is significantly affected, which may be related to compensate for the effects of airway space.

It Is Time for a Multidisciplinary Rehabilitation Approach: A Scoping Review on Stomatognathic Diseases in Neurological Disorders

Patients affected by neurological disorders can develop stomatognathic diseases (SD) related to decreased bite force and quality of mastication, bruxism, severe clicking and other temporomandibular disorders (TMD), which deeply affect patients' swallowing, masticatory and phonation functions and, therefore, their quality of life. The diagnosis is commonly based on medical history and physical examination, paying attention to the temporomandibular joint (TMJ) range of movements, jaw sounds and mandibular lateral deviation. Diagnostic tools such as computed tomography and magnetic resonance imaging are used instead in case of equivocal findings in the anamnesis and physical evaluation. However, stomatognathic and temporomandibular functional training has not been commonly adopted in hospital settings as part of formal neurorehabilitation. This review is aimed at describing the most frequent pathophysiological patterns of SD and TMD in patients affected by neurological disorders and their rehabilitative approach, giving some clinical suggestions about their conservative treatment. We have searched and reviewed evidence published in PubMed, Google Scholar, Scopus and Cochrane Library between 2010 and 2023. After a thorough screening, we have selected ten studies referring to pathophysiological patterns of SD/TMD and the conservative rehabilitative approach in neurological disorders. Given this, the current literature is still poor and unclear about the administration of these kinds of complementary and rehabilitative approaches in neurological patients suffering from SD and/or TMD.

Correlation between Temporomandibular Disorders (TMD) and Posture Evaluated trough the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD): A Systematic Review with Meta-Analysis

Background: Temporomandibular disorders (TMDs) are a series of disorders that affect the muscles and joint. Symptoms include joint pain, muscle pain, and limitation of mouth opening. One of several multifactorial diseases, temporomandibular dysfunction has mostly been linked to five etiological factors: occlusion, trauma, severe pain stimuli, parafunctional activities, and psychological elements, including stress, anxiety, and depression. The position of the human body as it is displayed in space is referred to as posture. Several nerve pathways regulate posture, and through ligaments, TMD and posture affect each other. The purpose of this study is to evaluate the possible correlation between posture and TMD through a meta-analysis of the literature; Methods: A literature search was performed on PubMed, Lilacs, and Web of science, and articles published from 2000 to 31 December 2022 were considered, according to the keywords entered. The term “temporomandibular disorders” has been combined with “posture”, using the Boolean connector AND; Results: At the end of the research, 896 studies were identified from the search conducted on the 3 engines. Only three were chosen to draw up the present systematic study summarizing the article’s main findings. The meta-analysis showed through forest plot analysis a correlation between posture and TMD Conclusions: This literature meta-analysis showed a correlation between posture and TMD. Nerve pathways probably regulate both body posture and mandibular posture. Further clinical studies will be needed to confirm this hypothesis and to indicate the main conclusions or interpretations.

Influence of occlusion and mandibular position on foot support and head posture in adult patients

OBJECTIVE

To study postural changes, taking into account different mandibular positions and the cephalic and plantar body segments.

METHODS

A cross-sectional, descriptive, clinical, and observational study was carried out on 76 patients, (mean age 28.79 years), in whom body posture and plantar support were evaluated in the maximum mandibular intercuspal position and the mandibular rest position without dental contact.

RESULTS

When the mandibular position was altered, 71.01% of the patients showed changes in the bipupillary line (p = 0.008), while those who did not show such changes did, however, show changes in plantar support. More than 85% of the sample experienced alterations in the plantar plane when the mandibular position was changed, with statistically significant results (p < 0.001).

CONCLUSION

There is a positive relationship between the different segments in body posture. In the sample, changes in plantar support with respect to the different mandibular positions were noticeable.

Assessment of posterior tilting of the hyoid bone in relation to carotid atherosclerosis: a CBCT study

Aim: The present study aimed to investigate whether the presence and areal and volumetric measurements of the unilateral extra-cranial carotid artery calcifications (ECACs) are associated with posterior tilting of the hyoid bone. Material and Method: A total of 658 cone-beam computed tomography (CBCT) scans were screened for the presence of ECACs. The calcifications were categorized as unilateral (right or left) or bilateral. Study group was consisted of cases with unilateral ECACs. A control group without ECACs matching with study group by age and gender was created. Volumetric and areal measurements in the ECAC group were done by using Mimics Medical software. Posterior tilting of the hyoid bone in relation to mid-sagittal plane and the dimension of posterior inclination through the greater horns were measured on i-Cat Vision software. Results: In total, 71 (10.8%) ECACs (30 bilateral and 41 unilateral) were detected. Study group consisted of 41 (6.2%) unilateral ECAC cases [25 (61%) females and 16 (39%) males]. Gender and age distributions were similar between ECAC and control groups. No significant difference between two groups was found considering the prevalence of posterior tilting of the hyoid bone (63.4% vs. 43.9%, p=0.240). Similarly, there was no significant difference in the mean dimension of posterior inclination between groups (2.48±2.12 mm. vs. 2.24±1.47 mm, p=0.646). The volume and areal measurements of calcifications were not correlated with the dimension of posterior inclination of the hyoid bone. Conclusion: Posterior tilting of the hyoid bone may be a frequent finding in cases of unilateral ECAC. However, the present findings suggest that no significant relationship exists between the presence of unilateral ECACs and posterior tilting of the hyoid bone.

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.

Cranio-cervical posture and rapid palatal expansion therapy

Objective:

Connections between craniocervical posture (CCP) and changes in teeth position have already been demonstrated; however, the defined pathway of relationship is still not clear. The aim of this study was to evaluate CCP modifications after rapid maxillary expansion therapy using rapid palatal expansion therapy (REP)/McNamara appliances.

Materials and Methods:

A consecutive series of 35 subjects, aged between 6 and 14 years, with no prior history of orthodontic treatment, and requiring skeletal expansion of the upper arch, were selected and analyzed. All patients were treated with REP or Mcnamara appliance: the active phase of 15 days and retaining phase of 6 months. Cephalometric analysis was carried out before (T0) and after (T1) orthodontic therapy evaluating changes in the craniofacial area and those related to CCP. The obtained data were statistically analyzed for the pre-post changes.

Results:

No statistically significant difference emerged indicating a modification in the CCP measured at T0 and T1 (P > 0.05). Patients treated with the McNamara appliance, compared to those treated with REP, showed a higher value of the angle OPT ^ Ver (P = 0.021), and a lower measure of the angles CVT^EVT (P = 0.035) and EVT^Ver (P = 0.023). Furthermore, patients treated with REP showed a higher hyoid angle value than those treated with McNamara (P = 0.047).

Conclusion:

This study did not reveal any relationship between the application of palatal expansion therapy and changes in CCP.

Biological Treatments for Temporomandibular Joint Disc Disorders: Strategies in Tissue Engineering

The temporomandibular joint (TMJ) is an important structure for the masticatory system and the pathologies associated with it affect a large part of the population and impair people's lifestyle. It comprises an articular disc, that presents low regeneration capacities and the existing clinical options for repairing it are not effective. This way, it is imperative to achieve a permanent solution to guarantee a good quality of life for people who suffer from these pathologies. Complete knowledge of the unique characteristics of the disc will make it easier to achieve a successful tissue engineering (TE) construct. Thus, the search for an effective, safe and lasting solution has already started, including materials that replace the disc, is currently growing. The search for a solution based on TE approaches, which involve regenerating the disc. The present work revises the TMJ disc characteristics and its associated diseases. The different materials used for a total disc replacement are presented, highlighting the TE area. A special focus on future trends in the field and part of the solution for the TMJ problems described in this review will involve the development of a promising engineered disc approach through the use of decellularized extracellular matrices.

Masticatory muscles electrical activity, stress and posture in preadolescents and adolescents with and without temporomandibular dysfunction

OBJECTIVE

To verify the difference between the masticatory muscles' electrical activity, stress signals and the posture of preadolescents and adolescents with and without temporomandibular dysfunction (TMD).

METHODS

24 preadolescents and adolescents aged between 11 and 18 years old were divided into two groups, TMD group (TMDG) and control group (CG). All subjects were submitted to anthropometric measurements, psychological stress analysis, temporomandibular joint clinical evaluation and TMD verification; postural evaluation and masseter and temporal muscles electrical activity analysis during chewing. For statistical analysis, the Student's t-test or Mann-Whitney U test were used according to data distribution.

RESULTS

There was a significant difference between the groups for the electrical activity of the right temporal muscles (7.43% ± 2.92 vs. 11.71% ± 5.37) and left (7.70% ± 4.04 vs.11.44% ± 4.03) in the inactive period of chewing between CG and TMDG, respectively. There was no difference in stress or posture variables between groups.

CONCLUSIONS

During the inactive period of chewing, there was greater activation of the temporal muscles in the TMDG. Female gender was prevalent in TMDG. The study participants showed signs of stress, regardless of the group. The posture and TMD relationship still need to be studied.

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.

Adding Temporomandibular joint treatments to routine physiotherapy for patients with non-specific chronic neck pain: A randomized clinical study

INTRODUCTION

Neck Pain can be related to the disorders of other adjacent areas such as the Temporomandibular Joint (TMJ). This study aimed to investigate whether there is value in adding TMJ treatments to routine physiotherapy in patients with non-specific chronic neck pain compared with a control group.

METHODS

A randomized, single-blind, clinical study desined including two groups of patients. Group A (20 people) received routine physiotherapy for neck pain and group B (20 people) received TMJ manual therapy plus exercise therapy in addition to routine physiotherapy for neck pain. The Treatment program included six sessions for two days a week over a period of 21 days. Assessments were performed during the first session, in the last session and one month after treatment as a follow-up. Outcome measures included neck range of motion (ROM), neck disability index (NDI) and visual analogue scale (VAS). Before starting the study, the reliability of methods for measuring neck ROM was evaluated.

RESULTS

Participants were 21 women and 19 men. Initially, a pilot study was carried out on the 40 volunteers to assess the reliability of the measurement methods, and the results were acceptable. With both the control group and the intervention group, the indexes showed significant improvement (p < 0.001), although the intervention group showed more improvement (p < 0.001).

CONCLUSION

This result means adding treatments of TMJ to routine neck physiotherapy can magnify the effect of the intervention, a significant change still in evidence at follow up. Moreover, given the clinically important differences, our results for VAS and NDI were acceptable.

Orofacial muscles activity in children with swallowing dysfunction and removable functional appliances

Swallowing dysfunction is a frequent disorder among children and refers to an altered tongue posture and abnormal tongue movement during swallowing. Removable functional appliance is one of the treatments applied by dentistry to correct this disorder. The aim of this study was to evaluate any differences on orofacial muscles activity in children with swallowing dysfunction with and without removable functional appliances. 68 children were eligible for the study and divided into the orthodontic group (OG) and the no-orthodontic group (NO-OG). Both groups performed a dental occlusion-class evaluation, a swallowing function test and a myoscan analysis in order to measure perioral forces (i.e. tongue extension force, lip pressure, masseter contraction force). Our results showed a significant difference (P=0.02) between OG and NO-OG for the tongue extension force, whereas no significant differences (P>0.05) were found for the other parameters. Our findings suggest that children with swallowing dysfunction and removable functional appliance show orofacial muscles activity within the range of reference values (except for the lip pressure). However, we hypothesize that orthodontic treatment can achieve more effective results with integration of myofunctional therapy.

Relationships of vertical facial pattern, natural head position and craniocervical posture in young Chinese children

OBJECTIVE

To investigate relationships of vertical facial patterns, natural head position (NHP), and craniocervical posture in young Chinese children with skeletal Class I relationship.

METHODS

Ninety-four patients with skeletal Class I relationship were classified into low, average, and high angle groups according to their mandibular plane angle (NSL/ML). Cephalometric radiographs in NHP were taken. Variables representing vertical and sagittal craniofacial morphology, head posture, and craniocervical posture were measured and compared.

RESULTS

Inclinations of the mandible to the true vertical and cervical column were smallest in the high angle group and largest in the low angle group. Other variables representing head posture and craniocervical posture were largest in the high angle group, smallest in the low angle group. Inclinations of ramus to cervical column were largest in the high angle group and smallest in the low angle group.

DISCUSSION

Subjects with large NSL/ML angles showed extended head and craniocervical posture, while subjects with small NSL/ML angles exhibited flexed head and craniocervical posture.