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

The Effect of Postural Rehabilitation on Pain, Balance, Mandibular Movement, and Posture in Temporomandibular Disorder Patients: A Comparison Between Posterior Edentulous and Dentate Groups

Objective: Posterior edentulism reduces occlusal support, thus increasing the risk and symptoms of temporomandibular disorder. No previous study has explored its effect on the treatment of temporomandibular disorders. This study aimed to examine the relationship between neck posture, balance, and posterior edentulism in patients with temporomandibular disorder and compare the effectiveness of physical therapy. Methods: In a quasi-experimental controlled trial, 26 patients with temporomandibular disorder were divided into 13 in the partly edentulous group and 13 in the dentate group. Both groups received manual therapy, postural exercises, deep neck flexor stabilization, and Kinesio tapping for 6 weeks. Each participant completed 12 physiotherapy sessions, administered twice weekly, with a minimum interval of 48 hours between sessions. Outcomes were assessed at baseline and after the 6-week program, including pain, mandibular movement, posture, and balance. Results: The physical therapy program significantly improved all measured outcomes (P < .05). Furthermore, the partially edentulous group showed more remarkable improvement in pain and balance compared to the dentate group (P < .05). Conclusions: Postural exercises effectively alleviate symptoms in patients with temporomandibular disorder, with more significant improvements observed in the partially edentulous group than in the dentate group.

Comparative Evaluation and Correlation of Hyoid Bone Position, Airway Dimension, and Psychological Status in Class II Vertical and Horizontal Malocclusion Cases With Temporomandibular Disorder Compared to Class I Non-Temporomandibular Disorder Cases

Introduction Temporomandibular disorder (TMD) involves discomfort and impaired function in the masticatory muscles and temporomandibular joint (TMJ), with a multifaceted etiology that includes biomechanical, neuromuscular, psychological, and biological factors. This research aims to assess and correlate the hyoid bone position, airway dimensions, and psychological status in class II Hz (horizontal) and Vt (vertical) malocclusion cases with TMD in contrast to non-TMD class I cases. Methodology This research was carried out at the Orthodontics Department, Sharad Pawar Dental College and Hospital, Sawangi, with consent obtained from the ethical committee. A total of 63 adult patients with class I, class II horizontal, and class II vertical malocclusions were selected. TMD was diagnosed using the Helkimo index, and patients were categorized accordingly. Psychological status was evaluated using the Warwick-Edinburgh scale, while the placement of hyoid bone and airway dimensions were assessed using lateral cephalograms. Statistical analysis involved descriptive and inferential statistics using SPSS version 27.0, with a significance level of p < 0.05. Results The research showed a noteworthy difference in the hyoid bone's location, airway dimensions, and psychological status among the three groups. Class II TMD patients (both vertical and horizontal) exhibited higher hyoid bone positions and larger Go-Hy-Me angles (angle formed by the gonion-hyoid line and the hyoid-menton line) compared to class I patients. In addition, class II vertical TMD patients showed the most reduced airway dimensions. Psychological assessments indicated higher stress, anxiety, and depression levels in class II TMD patients, particularly in the vertical group, compared to class I non-TMD patients. Conclusion This study highlights the intricate relationships between hyoid bone position, airway dimensions, and psychological status in TMD patients. TMD patients present with hyoid bones positioned closer to the cranium and mandible, larger Go-Hy-Me angles, and reduced airway dimensions. Psychological distress exacerbates TMD symptoms, negatively impacting overall well-being and quality of life. Orthodontists should consider these interrelated factors when devising treatment plans to improve patient outcomes. Future longitudinal studies with larger samples and advanced imaging techniques are recommended to further elucidate these interactions.

Craniocervical posture in patients with skeletal malocclusion and its correlation with craniofacial morphology during different growth periods

The association between craniocervical posture and craniofacial structures in the various sagittal skeletal malocclusion during different growth stages has been the focus of intense interest in fields of orthodontics, but it has not been conclusively demonstrated. Thus, this study aimed to investigate the association between craniofacial morphology and craniocervical posture in patients with sagittal skeletal malocclusion during different growth periods. A total of 150 from a large pool of cephalograms qualified for the inclusion and exclusion were evaluated and classified into three groups according to the Cervical Vertebral Maturation (CVM) by examining the morphological modifications of the second through fourth cervical vertebrae, each group consisted of 50 cephalograms. In each growth period, for the comparison of head and cervical posture differences among various skeletal classes, the radiographs were further subdivided into skeletal Class I (0° < ANB < 5°, n = 16), skeletal Class II (ANB ≥ 5°, n = 18), and skeletal Class III (0° ≤ ANB, n = 16) on the basis of their ANB angle. There was no significant difference in gender (P > 0.05). Some variables were found to be significant during pubertal growth and later in patients with sagittal skeletal malocclusion (P < 0.05). Most indicators describing craniocervical posture were largest in skeletal Class II and smallest in skeletal Class III during the peak growth periods and later. Cervical inclination variables were greater in skeletal Class III than in skeletal Class II. Variables of craniofacial morphology and craniocervical posture are more correlated during the pubertal growth period and later in patients with sagittal skeletal malocclusion. A tendency is an indication of the close interrelationship that a more extended head was in skeletal Class II while a flexed head was in skeletal Class III. Nevertheless, with the considerations of some limitations involved in this study, further longitudinal studies with large samples are required to elucidate the relationship clearly.

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 Between Occlusal Factors and Temporomandibular Disorders: A Systematic Literature Review

Temporomandibular disorders (TMD) originate from various components within the temporomandibular joint (TMJ), causing an impact on the masticatory muscles, the joint itself, and associated structures. They are a widely prevalent issue across the world. According to epidemiological research, up to 50% of adults in the population have TMD-related symptoms. The objective of this work was to analyze the existing scientific literature regarding the association between malocclusion classes, bruxism, and tooth loss in relation to the etiology of TMD. This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 analysis protocol. For the development of the question focus, the population, intervention, control, and outcomes (PICO) study design protocol was used. The question in focus according to the PICO format was: "Do malocclusion, tooth loss, and bruxism contribute to temporomandibular disorders?". The review was performed with articles from PubMed, Web of Science, and Google Scholar databases according to the specified inclusion and exclusion criteria. The included articles were not older than five years. The risk of bias was assessed in the included studies by using the Cochrane Risk-of-bias 2 (RoB-2) tool. Out of a total of 32 results received, 21 articles were chosen according to the established criteria after conducting a review and analysis of their full texts. The article search sequence was presented in the PRISMA 2020 flow diagram, and the outcomes of the chosen articles were presented. The literature results revealed a relationship between occlusion and the development of TMD. The influence of occlusal factors on the TMJ was explained by an examination of joint anatomy and symptoms related to TMD. This study revealed variations in TMJ factors across different malocclusion classes. Additionally, it was observed that the occurrence and attributes of TMD are influenced by the number of tooth loss quadrants and the frequency of missing teeth. Furthermore, a correlation was found between bruxism and the symptoms of TMD, including myofascial pain, disc displacement, arthralgia, and muscle disorders. This literature review provides comprehensive information on the relationship between malocclusion classes, bruxism, tooth loss, and TMDs. This prompts healthcare professionals to prioritize patients' occlusal assessment and TMJ condition.

Three-dimensional evaluation of upper pharyngeal airway, hyoid bone, and craniocervical changes following stabilization splint therapy in adult patients with temporomandibular joint disorders and mandibular deviation: A retrospective study

OBJECTIVE

This study aimed primarily to analyze the three-dimensional (3D) changes in the pharyngeal airway (PA), and secondarily, the hyoid bone (HB) and the craniocervical (CC) following stabilization splint (SS) therapy in adult patients with temporomandibular joint disorders (TMD) and mandibular deviation (MD).

METHODS

Thirty-five adult patients with TMD and MD, who were treated using SS with a mean age of 25.14 ± 6.11 years, were enrolled in this retrospective clinical study. Pre- and post-therapeutic cone-beam computed tomography (CBCT) scans were analyzed. PA dimension,nasopharyngeal, oropharyngeal, hypopharyngeal, sub-hypopharyngeal, and total pharyngeal airway spaces were measured in surface area, volume, minimum constricted area (MCA) and width, HB position, and CC posture were analyzed three-dimensionally using InVivo 6.0.3 and Dolphin 11.95 software. Wilcoxon rank-sum or Paired t-test was conducted, and P < 0.05 was considered significant.

RESULTS

SS therapy was administered for a period of 9.49 ± 4.02 months. The oropharyngeal airway space showed a significant decrease in sagittal width. The hypopharyngeal surface area, volume, MCA, and sagittal width decreased significantly. In terms of HB, hyoid-mandibular plane (H-MP), retrognathia-third vertebra's most inferior-anterior (RGN-C3ia), and retrognathia-Sella (RGN-S) distances significantly decreased. The Nasion-Sella line and the line that passes through C2ip to the odontoid process posterior tangent (NSL-OPT) angle in CC posture also decreased significantly.

CONCLUSION

SS therapy in TMD patients with MD mainly results in narrowing of the hypopharyngeal region, no change in HB position and improvement in head posture. These results undoubtedly assist in diagnosis and treatment of clinical conditions.

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.

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.

Craniofacial Morphology of Orthodontic Patients with and without Temporomandibular Disorders: A Cross-Sectional Study

Purpose

We aimed to explore the relationship between temporomandibular disorders (TMDs) and craniofacial morphology in orthodontic patients.

Methods

Altogether, 262 orthodontic patients were included and divided into two groups according to their Fonseca Anamnestic Index (FAI) scores: a no-TMD group (control group, FAI < 20) and a TMD group (FAI ≥ 20). Cephalometric parameters including cranial, maxillary, mandibular, and dental parameters were traced on cephalograms. Craniofacial morphology was compared between TMD and control groups, followed by subgroup analyses based on TMD severity, gender, age, and temporomandibular joint (TMJ) symptoms.

Results

The prevalence of TMDs was 52.7% among included patients (138/262). The mean age of TMD patients was higher than that of the control group. No significant difference in gender distribution between the groups was observed. The most commonly reported FAI items were misaligned teeth, neck pain, and emotional tension. The Frankfort-mandibular plane angle (FMA) was larger in the TMD patients than in the control group, whereas no significant differences in other parameters were observed. Subgroup analysis based on TMD severity revealed that FMA and anterior facial height of moderate/severe TMD patients were significantly larger than those of mild or no-TMD patients. Among male patients, the anterior cranial base length was smaller, and the anterior facial height was larger in the TMD group. Among female patients, no significant differences in craniofacial morphology between the groups were observed. In juvenile patients, overjet and overbite were smaller in the TMD group. In adult patients, SNA, ANB, FMA, and gonial angle were larger in the TMD group. Within the TMD group, patients with TMJ pain or noises exhibited characteristic craniofacial features compared to patients without these symptoms.

Conclusions

Orthodontic patients with TMDs have specific craniofacial morphology, suggesting a relationship between TMDs and particular craniofacial features in orthodontic patients.

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.