Cervical flexion-rotation test and physiological range of motion - A comparative study of patients with myogenic temporomandibular disorder versus healthy subjects

Temporomandibular disorder in individuals with spinal cord injuries

OBJECTIVE

This study evaluated Temporomandibular Disorder (TMD) in individuals with Spinal Cord Injuries (SCI) compared to individuals without physical disabilities.

DESIGN

Cross-sectional.

SETTING

International Fair of Technologies in Rehabilitation and Accessibility (REATECH) and School of Dentistry at the University of São Paulo (USP), Brazil.

PARTICIPANTS

In total, 19 patients with SCI and 19 patients without SCI (36.9 ± 11.4 years old) were examined by a calibrated examiner.

METHODS

using the following parameters: cervical spine mobility, palpation of muscle groups of the head and neck, functional manipulation of the lateral and medial pterygoids, and joint palpation (Diagnostic Criteria). The pattern and amplitude of mandibular movements were determined during screening using the Helkimo index.

STATISTICAL ANALYSES

Student's t-test, chi-square, Fisher's exact and Shapiro-Wilk test were used.

RESULTS

The groups did not differ in the presence of noise, pain, temporomandibular joint palpation, locking, dislocation, jaw pain, muscle sensitivity, or in pain, mobility of the cervical spine and functional manipulation. With respect to the jaw mobility index, the groups differed in range of movement (P = 0.020) and maximum right lateral movement (P = 0.007), with the worst values in the SCI group. The groups also differed in relation to lateral flexion in cervical mobility, in which the group without SCI presented better results (P = 0.046).

CONCLUSION

The Spinal Cord Injuries group showed higher levels of TMD in terms of range of movement, lateral flexion, and maximum right lateral movement, than the individuals without physical disabilities, demonstrating a clinical significance between cervical and mandibular disability in this group.

Electromyography: Processing, Muscles' Electric Signal Analysis, and Use in Myofunctional Orthodontics

Electromyography, commonly known as EMG, utilizes superficial or needle electrodes to record and analyze the fundamental electrical characteristics of skeletal muscles, determining whether the muscles are contracting. The motor unit, which consists of a collection of group muscle fibers and the motor neurons that govern them, is the structural basis of EMG. Three types of electrode are used in EMG which are needle electrode, fine wire electrode, and surface electrode. A significant amount of literature indicates that the correction of muscle function affects the relationships between teeth within the same jaw and between the jaws on opposing sides. The mechanism of action in myofunctional appliance therapy is linked to neuromuscular and skeletal adaptations resulting from altered function in the orofacial region. Both myofunctional therapy and orthodontics aim to address abnormal muscular behavior, restore abnormal muscle activity, and maintain proper alignment in various areas, including the lips, lower jaw, and tongue. This knowledge is essential for functions such as swallowing, speaking, chewing, and respiration as well as for minimizing incorrect movements and positioning. This article aims to describe the application of surface EMG as a diagnosis tool for assessing muscle activities in various orthodontic disorders, such as class II malocclusion open bite, crossbite, maxillary constriction, cleft lip and palate (CLP), and temporomandibular dysfunction, in patients. The electrodes used in EMG can be utilized to detect bioelectric activity in the muscles of the jaws and abnormalities in jaw movement. Analyzing EMG data is vital for obtaining a comprehensive understanding of the masticatory muscle system.

Morphological Changes of the Suboccipital Musculature in Women with Myofascial Temporomandibular Pain: A Case-Control Study

Temporomandibular disorder (TMD) is an umbrella term including pain problems involving the cranio-cervical region. It has been suggested that patients with TMD also exhibit cervical spine disturbances. Evidence suggests the presence of morphological changes in the deep cervical muscles in individuals with headaches. The objective of this study was to compare the morphology of the suboccipital muscles between women with TMD and healthy controls. An observational, cross-sectional case-control study was conducted. An ultrasound examination of the suboccipital musculature (rectus capitis posterior minor, rectus capitis posterior major, oblique capitis superior, oblique capitis inferior) was conducted in 20 women with myofascial TMD and 20 matched controls. The cross-sectional area (CSA), perimeter, depth, width, and length of each muscle were calculated by a blinded assessor. The results revealed that women with myofascial TMD pain exhibited bilaterally reduced thickness, CSA, and perimeter in all the suboccipital muscles when compared with healthy women. The width and depth of the suboccipital musculature were similar between women with myofascial TMD and pain-free controls. This study found morphological changes in the suboccipital muscles in women with myofascial TMD pain. These changes can be related to muscle atrophy and are similar to those previously found in women with headaches. Future studies are required to investigate the clinical relevance of these findings by determining if the specific treatment of these muscles could help clinically patients with myofascial TMD.

Headache and orofacial pain: A traffic-light prognosis-based management approach for the musculoskeletal practice

Introduction

Headache (HA) is one of the most prevalent disabling conditions worldwide and is classified as either primary or secondary. Orofacial pain (OFP) is a frequent pain perceived in the face and/or the oral cavity and is generally distinct from a headache, according to anatomical definitions. Based on the up-to-date classification of the International Headache Society, out of more than 300 specific types of HA only two are directly attributed to the musculoskeletal system: The cervicogenic HA and HA attributed to temporomandibular disorders. Because patients with HA and/or OFP frequently seek help in the musculoskeletal practice, a clear and tailored prognosis-based classification system is required to achieve better clinical outcomes.

Purpose

The aim of perspective article is to suggest a practical traffic-light prognosis-based classification system to improve the management of patients with HA and/or OFP in the musculoskeletal practice. This classification system is based on the best available scientific knowledge based on the unique set-up and clinical reasoning process of musculoskeletal practitioners.

Implications

Implementation of this traffic-light classification system will improve clinical outcomes by helping practitioners invest their time in treating patients with significant involvement of the musculoskeletal system in their clinical presentation and avoid treating patients that are not likely to respond to a musculoskeletal based intervention. Furthermore, this framework incorporates medical screening for dangerous medical conditions, and profiling the psychosocial aspects of each patient; thus follows the biopsychosocial rehabilitation paradigm.

Chronic craniomandibular pain after craniotomy: A long-term clinical study

OBJECTIVE

Chronic craniomandibular/cervical pain and temporomandibular disorders have not been studied in patients who had a craniotomy several years previously. The aim of the current clinical work was to address these issues.

METHODS

A total group of 150 ambulant patients who had a previous craniotomy was subclassified according to whether or not the temporalis muscle was manipulated.

RESULTS

The average incidence of multiple subsite regional head and neck pain was 69.3% a number of years after a craniotomy. Evidence of internal derangement of the temporomandibular joint was significantly higher in the group that required manipulation of the temporalis muscle during the procedure.

CONCLUSION

The pattern of chronic craniomandibular/cervical pain experienced years after a craniotomy supports the brain neuromatrix theory of pain.

Neural Basis of Etiopathogenesis and Treatment of Cervicogenic Orofacial Pain

(1) Background and Objectives: The aim of this narrative review was to analyze the neuroanatomical and neurophysiological basis of cervicogenic pain in cervico-cranial pain syndromes, focusing particularly on cervico-orofacial syndromes as a background for the proper diagnosis and non-surgical treatment. Relevant literature on the topic from past 120 years has been surveyed. (2) Material and Methods: We surveyed all original papers, reviews, or short communications published in the English, Spanish, Czech or Slovak languages from 1900 to 2020 in major journals. (3) Results: The cervicogenic headache originates from the spinal trigeminal nucleus where axons from the C₁–C₃ cervical spinal nerves and three branches of the trigeminal nerve converge (trigeminocervical convergence) at the interneurons that mediate cranio-cervical nociceptive interactions. The role of the temporomandibular joint in the broad clinical picture is also important. Despite abundant available experimental and clinical data, cervicogenic orofacial pain may be challenging to diagnose and treat. Crucial non-surgical therapeutic approach is the orthopedic manual therapy focused on correction of body posture, proper alignment of cervical vertebra and restoration of normal function of temporomandibular joint and occlusion. In addition, two novel concepts for the functional synthesis of cervico-cranial interactions are the tricentric concept of mouth sensorimotor control and the concept of a cervicogenic origin of bruxism. (4) Conclusions: Understanding the basis of neuroanatomical and neurophysiological neuromuscular relations enables an effective therapeutic approach based principally on orthopedic manual and dental occlusal treatment.

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.

Alterations in kinematics of temporomandibular joint associated with chronic neck pain

BACKGROUND

Temporomandibular disorder (TMD) is an umbrella term for pain and dysfunction of the temporomandibular joint (TMJ) and its associated structures. Patients with TMD show changes in TMJ kinematics and masticatory muscle activation. TMD is commonly comorbid with non-specific chronic neck pain (NCNP), which may be one of the risk factors for TMD.

OBJECTIVES

This study aimed to investigate whether patients with NCNP have altered TMJ kinematics and masticatory muscle activity.

METHODS

This was a cross-sectional exploratory study including 19 healthy participants and 20 patients with NCNP but without TMD symptoms. TMJ kinematics was measured during mouth opening and closing, jaw protrusion and jaw lateral deviation. Surface electromyography was used to record the muscle activity of the anterior temporalis, masseter, sternocleidomastoid and upper trapezius while clenching. Furthermore, cervical posture, cervical range of motion (ROM) and pressure-pain threshold of the neck and masticatory muscles were measured.

RESULTS

Compared with the healthy group, the NCNP group showed significantly reduced upper cervical rotation ROM (p = .041) and increased condylar path length (p = .02), condylar translation (opening p = .034, closing p = .011) and mechanical pain sensitivity of the upper trapezius (p = .018). Increased condylar translation was significantly correlated with reduced upper cervical mobility and poor cervical posture (r = -0.322 to -0.397; p = .012-.046).

CONCLUSION

Increased condylar translation and path length in patients with NCNP may indicate poor control of TMJ articular movement, which may result from neck pain or may be a compensation for limited neck mobility. Evaluation of excessive TMJ translation may be considered in patients with NCNP.

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.

Cervical musculoskeletal disorders in patients with temporomandibular dysfunction: A systematic review and meta-analysis

OBJECTIVE

To verify which are the neck musculoskeletal disorders presented by individuals with temporomandibular disorders (TMD).

METHODS

It is a systematic review and meta-analysis that were included cohort, case-control and cross-section studies that analyzed the presence of cervical musculoskeletal disorders in individuals with TMD, with age between 18 and 55 years. The searches were carried out in the databases: Medline/PubMed, Cinahl, Web of Science, Cochrane, Lilacs and Scopus; and there was no linguistic or temporal restriction. The evidence quality was evaluated by GRADE system and methodological quality by Newcastle-Ottawa Quality Assessment Scale (NOS) and the risk of publication bias assessed by the funnel plot graph. The data was quantitatively analyzed by the meta-analysis using the mean differences (MD) as an effect measure.

RESULTS

There were included 21 manuscripts in the synthesis, of theses 16 were evaluated by meta-analysis with methodological quality ranging from poor to excellent by NOS scale. Individuals with TMD present lower endurance of extensor neck muscle compared to TMD-free (MD = -194.66s [95%CI: 212.44;-176.88]), with moderate to excellent quality. As, upper neck hymobility on the right (MD = -8.59° (95%CI: -10.43°;-6.75°) and left (MD = -7.99° (95%CI: -9.63°;-6.35°), and in all global neck movements. Also, individuals with TMD presented worse self-reported neck disability (MD = 7.91 (95%CI: 7.39; 8.43)) compared to free-TMD.

CONCLUSION

There is moderate and strong evidence that patients with TMD present lower endurance of extensor neck muscle, global and upper neck hypomobility, worse self-reported neck disability, however, their cranio-cervical posture is similar to individuals without TMD, based on a moderate to excellent methodological quality.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42018103918.

1H-NMR-Based salivary metabolomics from females with temporomandibular disorders - A pilot study

Although temporomandibular disorder (TMD) is the second most common musculoskeletal disorder in the general population, the disease is multifactorial and presents symptoms common to other conditions which misdiagnosis can lead to treatment failure. In this case-control study, we performed, for the first time, a high-resolution ¹H-nuclear magnetic resonance spectroscopy metabolomic analysis of the saliva of 26 women with TMD of muscular origin (experimental group [EG]) at the beginning (EG-pre) and at the end (EG-post) of a conservative treatment, and of 27 normal women (control group [CG]) to identify a metabolic signature for TMD. One-way analysis of variance showed changes in the concentration of phenylacetate, dimethylamine, maltose, acetoin, and isovalerate. Partial least-square discriminant analysis showed that metabolite signals did not overlap in CG X EG-pre and EG-pre X EG-post, but overlapped in CG X EG-post. The area under the receiver operating characteristic curve was 1 in CG X EG-pre (95% CI, 1.000-1.000; p < 0.002), 0.993 in EG-pre X EG-post (95% CI, 0.963-1.000), and 0.832 in CG X EG-post (95% CI, 0.699-0.961). These results suggest that the metabolomic profiles of women with and without TMD differ, while after treatment there is a lower distinction and slight tendency towards overlapping between CG and EG-post compared to pre treatment. We also found that phenylacetate, dimethylamine, maltose, acetoin, and isovalerate are potential biomarkers for TMD of muscular origin.

Relationship between specific temporomandibular disorders and impaired upper neck performance

Upper neck impairments are more prevalent in patients with temporomandibular disorders (TMDs) but the differences between specific types of TMDs are unclear. This study evaluated the distribution of such impairments among different forms of TMD. In total, 116 participants (86 women and 30 men, age range 21-75 yr) were investigated. Forty-two individuals had no TMDs and were assigned to the control group. The remaining 74 patients were assigned to one of three groups based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) findings: pain-related (n = 37); intra-articular (n = 17); or mixed (combined pain-related and intra-articular) (n = 20). Analyses of impairments included between-group comparisons of key parameters of upper neck performance (active/passive mobility and muscular capabilities) and pain (subjective neck disability and pain sensitivity). Patients in the pain-related and mixed TMD groups were found to have decreased upper neck mobility in the cervical flexion-rotation test compared with patients in intra-articular and control groups, as well as poorer capabilities of the deep neck flexor muscles in the cranio-cervical flexion test compared to the control group. It was concluded that patients with pain-related TMD diagnoses are more likely to experience significant upper-neck hypomobility and poor muscular capabilities than patients with intra-articular diagnoses of TMD.

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.

A comparative clinical study of arthrogenous versus myogenous temporomandibular disorder in patients presenting with Costen's syndrome

Objective: Costen's syndrome involves otoneurological and sinonasal symptoms associated with temporomandibular disorder (TMD). The current study compared the symptoms related to Costen's syndrome in patients with arthrogenous versus myogenous TMD.Methods: The study involved 294 consecutive patients with TMD, prospectively examined over a period of 6 months. These were stratified into 180 patients with arthrogenous TMD and 114 patients with myogenous TMD. A questionnaire and examination protocol was applied for each patient.Results: Sinonasal symptoms were more common in the arthrogenous group (p = .001), whereas, hearing loss and vertigo were more common in the myogenous group (p = .001).Conclusion: The current study provides support for central nervous system neuroplastic changes in the genesis of Costen's syndrome symptoms.

Temporomandibular joint disorder determined by Fonseca anamnestic index and associated factors in 18- to 27-year-old university students

OBJECTIVE

The aim of this study was to investigate temporomandibular disorder (TMD) and associated risk factors.

METHODS

This study was conducted using 212 university students. Based on the Fonseca anamnestic index, the population was divided into two groups: those with TMD and those without TMD. The two groups were compared in terms of global body posture, craniohorizontal and craniovertebral angles, neck and temporomandibular joint range of motion, stress level, and sleep quality.

RESULTS

Stress level, sleep quality, and left cervical rotation were found to have statistical differences between the groups (p = 0.00, 0.00, and 0.046, respectively). Sleep quality and stress level were found to be important risk factors for the presence of TMD (p = 0.017 and 0.00, respectively).

DISCUSSION

In the prevention and treatment of TMD, a holistic approach that evaluates mechanical factors and psychosocial factors should be adopted.