Diagnosis and treatment of temporomandibular disorders: an ethical analysis of current practices

Anatomical factors influencing temporomandibular joint clicking in young adults: temporomandibular joint structure disorder or lateral pterygoid muscle dysfunction?

Objective: This study aimed to investigate the selected anatomical factors that can potentially influence temporomandibular joint (TMJ) clicking in young adults by assessing TMJ structures and lateral pterygoid muscle (LPM) function using magnetic resonance imaging (MRI). Methods: The patients were divided into four groups: the healthy control group; the clicking on mouth opening group; the clicking on mouth closing group; and the clicking on mouth opening and closing group. Additionally, we used clinical palpation to evaluate the masticatory muscles' functional state and employed MRI using the OCOR-T1WI-FSE-CLOSED, OSAG-PDW-FSE-CLOSED, and OSAG-PDW-FSE-OPEN sequences to analyze the texture of the lateral pterygoid muscle (LPM). Results: The proportion of any articular disc or condylar morphology class did not differ significantly between the TMJ clicking and HC groups. The articular disc position did not differ significantly between the TMJ clicking and HC groups. In the TMJ clicking group, the presence of masticatory muscle dysfunction differed significantly between the clicking and non-clicking sides. Moreover, the LPM accounted for the highest proportion among masticatory muscles with tenderness in all TMJ clicking subgroups (77.78%-100%). Therefore, in the TMJ clicking group, the LPM texture was less defined, more uniform in gray scale, and more similar to local texture (p < 0.0001). Conclusion: The occurrence of TMJ clicking in young adults is unrelated to the TMJ structure but related to the function of masticatory muscles, particularly the LPM.

Evaluation of the effect of different kinds of treatment modalities for temporomandibular joint pain and its relevance to chronic cervical pain: A randomized controlled trial

AIM

The aim of this study was to evaluate the effect of different treatment modalities for temporomandibular joint (TMJ) pain and their relevance to chronic cervical pain after 12 months.

SETTINGS AND DESIGN

This was a randomized controlled trial.

MATERIALS AND METHODS

Forty-eight participants with chronic cervical and TMJ pain were selected using research diagnostic criteria and randomized into four groups (n = 12), which included control, soft splints, transcutaneous electrical nerve stimulation (TENS), and low-level laser (LLL). The cervical and TMJ pain was recorded using visual analog scale (VAS) scores at baseline, 3 months, 6 months, and 12 months. Occlusal equilibration was done for all groups except for the control.

STATISTICAL ANALYSIS USED

The mean pain scores were statistically analyzed using one-way analysis of variance and posthoc test.

RESULTS

The mean VAS scores in TMJ pain patients between the four groups at baseline and at final follow-up were 7.27 ± 1.29 in Group 1, 7.53 ± 0.70 in Group 2, 7.76 ± 0.80 in Group 3, and 7.61 ± 0.61 in Group 4. The mean difference between Groups 1 and 3, Groups 1 and 4, and Groups 2 and 3 was statistically significant (P < 0.00). Pearson correlation test yielded a mild and negative correlation between TMJ and cervical pain.

CONCLUSION

TENS and LLL were found to be equally effective in reducing pain in the jaw joint region, followed by soft splints, and there was no correlation between TMJ and cervical pain.

Chewing performance of patients with worn dentition before and after restorations: A scoping review

BACKGROUND

Tooth wear is a multifactorial complex process related to the loss of dental tissue, due to chemical or mechanical processes, by abrasion, attrition, erosion. Restorative treatment represents an attempt to rebuild and recreate the lost structure.

OBJECTIVE

This scoping review aims to investigate whether restorative treatment of worn dentition (either with direct or indirect adhesive composite adhesive procedures or with prosthetic techniques) can have an impact on the masticatory performance parameters.

METHODS

A scoping review was conducted on multiple databases (Pubmed, Medline CENTRAL, ICTRP), following the PRISMA guidelines. Abstracts of research papers were screened for suitability, and full-text articles were obtained for those who satisfied the inclusion and exclusion criteria.

RESULTS

Only one article meet the inclusion criteria of the review. Restorative treatment of worn dentition although have a positive impact on the self-report ability to chew, has no effect on the masticatory performance test.

CONCLUSION

At the moment, not enough evidence to comment on the actual therapeutic role of restorative treatment on tooth wear is available. Clinicians, before taking any clinical decision, should carefully discuss with patients the needs and expectations of the treatment plan.

Management of chronic pain associated with temporomandibular disorders: a clinical practice guideline

CLINICAL QUESTION

What is the comparative effectiveness of available therapies for chronic pain associated with temporomandibular disorders (TMD)?

CURRENT PRACTICE

TMD are the second most common musculoskeletal chronic pain disorder after low back pain, affecting 6-9% of adults globally. TMD are associated with pain affecting the jaw and associated structures and may present with headaches, earache, clicking, popping, or crackling sounds in the temporomandibular joint, and impaired mandibular function. Current clinical practice guidelines are largely consensus-based and provide inconsistent recommendations.

RECOMMENDATIONS

For patients living with chronic pain (≥3 months) associated with TMD, and compared with placebo or sham procedures, the guideline panel issued: (1) strong recommendations in favour of cognitive behavioural therapy (CBT) with or without biofeedback or relaxation therapy, therapist-assisted mobilisation, manual trigger point therapy, supervised postural exercise, supervised jaw exercise and stretching with or without manual trigger point therapy, and usual care (such as home exercises, stretching, reassurance, and education); (2) conditional recommendations in favour of manipulation, supervised jaw exercise with mobilisation, CBT with non-steroidal anti-inflammatory drugs (NSAIDS), manipulation with postural exercise, and acupuncture; (3) conditional recommendations against reversible occlusal splints (alone or in combination with other interventions), arthrocentesis (alone or in combination with other interventions), cartilage supplement with or without hyaluronic acid injection, low level laser therapy (alone or in combination with other interventions), transcutaneous electrical nerve stimulation, gabapentin, botulinum toxin injection, hyaluronic acid injection, relaxation therapy, trigger point injection, acetaminophen (with or without muscle relaxants or NSAIDS), topical capsaicin, biofeedback, corticosteroid injection (with or without NSAIDS), benzodiazepines, and β blockers; and (4) strong recommendations against irreversible oral splints, discectomy, and NSAIDS with opioids.

HOW THIS GUIDELINE WAS CREATED

An international guideline development panel including patients, clinicians with content expertise, and methodologists produced these recommendations in adherence with standards for trustworthy guidelines using the GRADE approach. The MAGIC Evidence Ecosystem Foundation (MAGIC) provided methodological support. The panel approached the formulation of recommendations from the perspective of patients, rather than a population or health system perspective.

THE EVIDENCE

Recommendations are informed by a linked systematic review and network meta-analysis summarising the current body of evidence for benefits and harms of conservative, pharmacologic, and invasive interventions for chronic pain secondary to TMD.

UNDERSTANDING THE RECOMMENDATION

These recommendations apply to patients living with chronic pain (≥3 months duration) associated with TMD as a group of conditions, and do not apply to the management of acute TMD pain. When considering management options, clinicians and patients should first consider strongly recommended interventions, then those conditionally recommended in favour, then conditionally against. In doing so, shared decision making is essential to ensure patients make choices that reflect their values and preference, availability of interventions, and what they may have already tried. Further research is warranted and may alter recommendations in the future.

Centric relation-A biological perspective of a technical concept

BACKGROUND

Few terms and concepts have been so extensively debated in dentistry as the words 'centric relation' (CR). Debates involve its biological, diagnostic and therapeutic usefulness.

METHODS

A review of the literature on the current concepts on CR as a diagnostic or therapeutic aid in dentistry was provided. Clinical trials assessing the superiority of one CR recording method over the others to identify patients with temporomandibular disorders (diagnostic use) or to manage patients with prosthodontic or orthodontic needs (therapeutic use) were tentatively included.

RESULTS

Due to the absence of literature addressing either of the above targets, a comprehensive overview was provided. The diagnostic use of CR as a reference position to identify the correct position of the temporomandibular joint condyle within the glenoid fossa is not supported and lacks anatomical support. From a therapeutic standpoint, the use of CR can be pragmatically useful in prosthodontics as a maxillo-mandibular reference position when occlusal re-organization is warranted and/or when the position of maximum intercuspation is no longer available.

CONCLUSIONS

The derived occlusal goals from a diagnostic misuse of CR are generally the result of circular reasoning, that is a technique is based on the recording of a certain condylar position that is believed to be 'ideal' and the treatment is considered successful when such position is shown by the specific instrument that was manufactured for that purpose. The term 'Centric Relation' might be replaced with the term 'Maxillo-Mandibular Utility Position'.

Building the foundation for a modern patient-partnered infrastructure to study temporomandibular disorders

Background

Conflicting reports from varying stakeholders related to prognosis and outcomes following placement of temporomandibular joint (TMJ) implants gave rise to the development of the TMJ Patient-Led RoundTable initiative. Following an assessment of the current availability of data, the RoundTable concluded that a strategically Coordinated Registry Network (CRN) is needed to collect and generate accessible data on temporomandibular disorder (TMD) and its care. The aim of this study was therefore to advance the clinical understanding, usage, and adoption of a core minimum dataset for TMD patients as the first foundational step toward building the CRN.

Methods

Candidate data elements were extracted from existing data sources and included in a Delphi survey administered to 92 participants. Data elements receiving less than 75% consensus were dropped. A purposive multi-stakeholder sub-group triangulated the items across patient and clinician-based experience to remove redundancies or duplicate items and reduce the response burden for both patients and clinicians. To reliably collect the identified data elements, the identified core minimum data elements were defined in the context of technical implementation within High-performance Integrated Virtual Environment (HIVE) web-application framework. HIVE was integrated with CHIOS™, an innovative permissioned blockchain platform, to strengthen the provenance of data captured in the registry and drive metadata to record all registry transaction and create a robust consent network.

Results

A total of 59 multi-stakeholder participants responded to the Delphi survey. The completion of the Delphi surveys followed by the application of the required group consensus threshold resulted in the selection of 397 data elements (254 for patient-generated data elements and 143 for clinician generated data elements). The infrastructure development and integration of HIVE and CHIOS™ was completed showing the maintenance of all data transaction information in blockchain, flexible recording of patient consent, data cataloging, and consent validation through smart contracts.

Conclusion

The identified data elements and development of the technological platform establishes a data infrastructure that facilitates the standardization and harmonization of data as well as perform high performance analytics needed to fully leverage the captured patient-generated data, clinical evidence, and other healthcare ecosystem data within the TMJ/TMD-CRN.

Long-Term Effects of a Single Application of Botulinum Toxin Type A in Temporomandibular Myofascial Pain Patients: A Controlled Clinical Trial

This study assessed the long-term effects of botulinum toxin type A (BoNT-A) in subjective pain, pain sensibility, and muscle thickness in persistent myofascial temporomandibular-disorder pain (MFP-TMD) patients. Fourteen female subjects with persistent MFP received BoNT-A treatment with different doses (10U-25U for temporalis muscle and 30U-75U for masseter muscle). The treatment was injected bilaterally in the masseter and anterior temporalis muscles in a single session. Clinical measurements included: self-perceived pain (VAS), pain sensibility (PPT), and muscles thickness (ultrasonography). Follow-up occurred 1, 3, 6, and 72 months after treatment for VAS and PPT and 1, 3, and 72 months for ultrasonography. For statistical analysis, the Friedman test with the Bonferroni test for multiple comparisons as a post hoc test was used for non-parametric repeated measures comparisons among the evaluation times. A 5% probability level was considered significant in all tests. VAS values presented a significant decrease throughout the study (p < 0.05). Regarding PPT values, a significant increase was found when comparing baseline data with post-treatment follow-ups (p < 0.05), and even though a significant decrease was found in muscle thickness when baseline values were compared with the 1- and 3-months assessments, no differences were found when compared with the 72 months follow-up (p > 0.05). A single injection of BoNT-A presents long-term effects in reducing pain in persistent MFP-TMD patients, and a reversibility of adverse effects on masticatory-muscle thickness.

Celecoxib in the treatment of orofacial pain and discomfort in rats subjected to a dental occlusal interference model

Purpose:

To evaluate the effect of a selective cyclooxygenase 2 (COX-2) inhibitor on trigeminal ganglion changes and orofacial discomfort/nociception in rats submitted to an experimental model of dental occlusal interference (DOI).

Methods:

Female Wistar rats (180-200 g) were divided into five groups: a sham group (without DOI) (n=15); and four experimental groups with DOI treated daily with 0.1 mL/kg saline (DOI+SAL), 8, 16, or 32 mg/kg celecoxib (DOI+cel -8, -16, -32) (n=30/group). The animals were euthanized after one, three, and seven days. The bilateral trigeminal ganglia were analyzed histomorphometrically (neuron cell body area) and immunohistochemically (COX-2, nuclear factor-kappa B [NFkB], and peroxisome proliferator-activated receptor-y [PPARy]). A bilateral nociception assay of the masseter muscle was performed. The number of bites/scratches, weight, and grimace scale scores were determined daily. One-way/two-way analysis of variance (ANOVA)/Bonferroni post hoc tests were used (P < .05, GraphPad Prism 5.0).

Results:

DOI+SAL showed a reduction in neuron cell body area bilaterally, whereas DOI+cel-32 exhibited a significative increase in neuron cell body area compared with DOI+SAL group (P < 0.05). The ipsilateral (P=0.007 and P=0.039) and contralateral (P < 0.001 and P=0.005) overexpression of COX-2 and NFkB and downregulation of PPARy (P=0.016 and P < 0.001) occurred in DOI+SAL, but DOI+cel-32 reverted this alteration. DOI+SAL showed increase in isplateral (P < 0.001) and contralateral (P < 0.001) nociception, an increased number of bites (P=0.010), scratches (P < 0.001), and grimace scores (P=0.032). In the group of DOI+cel-32, these parameters were reduced.

Conclusions:

Celecoxib attenuated DOI-induced transitory nociception/orofacial discomfort resulting from trigeminal COX-2 overexpression.

Manual therapy for temporomandibular disorder in older adults: an integrative literature review

ABSTRACT Purpose: to describe the manual therapy techniques used to treat the temporomandibular disorder in older adults. Methods: an integrative literature review assessing scientific publications indexed in six databases: MEDLINE/PubMed, Web of Science, CINAHL, Scopus, LILACS, and PEDro. Only intervention studies were included, with no restriction of date or language. The articles included in the review were assessed with the Critical Appraisal Skills Programme. Results: after consulting the databases, 88 articles were found, six of which were considered eligible. No study was found exclusively approaching older adults. According to the analysis of the risk of bias, two articles were classified as low-risk, two as intermediate, and two as high-risk. The manual therapy techniques were intra- and extraoral massage, temporomandibular joint and cervical spine mobilization, myofascial release, trigger-point finger pressure, and deep transverse massage. Conclusion: the studies observed improved mandibular movements and masticatory function, eased pain, and reduced anxiety.

Terapia manual na disfunção temporomandibular em pessoas idosas: uma revisão integrativa da literatura

ABSTRACT Purpose: to describe the manual therapy techniques used to treat the temporomandibular disorder in older adults. Methods: an integrative literature review assessing scientific publications indexed in six databases: MEDLINE/PubMed, Web of Science, CINAHL, Scopus, LILACS, and PEDro. Only intervention studies were included, with no restriction of date or language. The articles included in the review were assessed with the Critical Appraisal Skills Programme. Results: after consulting the databases, 88 articles were found, six of which were considered eligible. No study was found exclusively approaching older adults. According to the analysis of the risk of bias, two articles were classified as low-risk, two as intermediate, and two as high-risk. The manual therapy techniques were intra- and extraoral massage, temporomandibular joint and cervical spine mobilization, myofascial release, trigger-point finger pressure, and deep transverse massage. Conclusion: the studies observed improved mandibular movements and masticatory function, eased pain, and reduced anxiety.

Temporomandibular disorder treatment algorithm for otolaryngologists

OBJECTIVE

To review current literature describing the management of temporomandibular disorder (TMD) and to propose an evidence-based algorithm for otolaryngologists.

DATA SOURCES

A literature review using PubMed and Scopus was conducted to identify manuscripts that describe TMJ disorder etiology, diagnostic methods, and management across the fields of otolaryngology, general practice medicine, physical therapy, dentistry, and maxillofacial surgery.

REVIEW METHODS

Two reviewers subjectively evaluated the studies based on the inclusion criteria, incorporating them into a comprehensive algorithm.

CONCLUSIONS

TMD is one of the most common conditions presenting to otolaryngology outpatient clinics. Etiologies of TMD vary widely, including myofascial, intraarticular, neurologic, traumatic, or psychiatric in origin. When conservative measures fail to produce symptom relief, alternative treatments and referral to outside specialists including psychiatry, physical therapy, dentistry, and maxillofacial surgery may be indicated. Premature or inappropriate referrals may lead to patients suffering TMD for extended periods of time, with alternating referrals between various specialists. Thus, we present a TMD treatment algorithm for otolaryngologists to aid in the decision-making process in managing TMD.

IMPLICATIONS FOR PRACTICE

Patients frequently present to otolaryngology outpatient clinics for symptoms of TMD. Multidisciplinary practice may be necessary to effectively treat TMD of varying etiology and severity. Following conservative treatment, appropriate referrals and treatment plans will reduce ineffective use of resources, deferral of treatment, and patient suffering. For this reason, a comprehensive algorithm for otolaryngologists will improve resource utilization and efficiency of treatment to ultimately provide improved treatment outcomes for patients.

Nonsurgical treatment of class III malocclusion with temporomandibular disorder comorbidity: A clinical report

The treatment of a 57-year-old woman with combined skeletal and pseudo-class III malocclusion who was also suffering from chronic myofascial orofacial pain is described. The challenge was to treat the patient's malocclusion while simultaneously managing the temporomandibular disorder. After a successful 3-month occlusal device therapy, which substantially reduced the patient's discomfort, a nonsurgical therapy by using complete-mouth fixed restorations was planned. The treatment was first tested by using printed interim restorations before monolithic zirconia restorations were provided. Stable occlusion and a pain-free outcome were observed at the 3-month follow-up.

Transitioning to chronic temporomandibular disorder pain: A combination of patient vulnerabilities and iatrogenesis

Background

Based on a variety of studies conducted in recent years, some of the factors that might contribute to the negative treatment responses of some TMD patients have been elucidated.

Methods

This paper describes known vulnerability factors that make individuals susceptible to developing temporomandibular disorders (TMDs), as well as those that contribute to the perpetuation of such problems. In addition, the topic of iatrogenesis is discussed as a major contributor to the negative outcomes that can be seen in this field.

Results

At the patient level, anatomical, psychosocial and genetic factors may contribute to individual vulnerability. The anatomy and pathophysiology of muscles, joints, disc and nerves may all be involved in predisposing to TMD symptoms, especially when the patients have pain elsewhere in the body. Among the psychosocial factors, some features may be elucidated by the DC/TMD axis II, while others (eg illness behaviour, Munchausen syndrome, lack of acceptance of non‐mechanical approaches) require careful evaluation by trained clinicians. Genetic predisposition to first onset TMDs and to chronification of symptoms has been identified for individuals with certain psychological traits, presence of comorbid conditions and certain abnormal clinical manifestations. Regarding iatrogenesis, sins of omission may influence the clinical picture, with the main ones being misdiagnosis and undertreatment. Joint repositioning strategies, occlusal modifications, abuse of oral appliances, use of diagnostic technologies, nocebo effect and complications with intracapsular treatments are the most frequent sins of commission that may contribute to chronification of TMDs. The patients who present with massive occlusal and jaw repositioning changes combined with persistent severe orofacial pain are not a rarity within TMD and orofacial pain canters; these patients are the most difficult ones to manage because of this horrific combination of negative factors.

Conclusions

The information presented in this paper will help clinicians to understand better why some individuals develop temporomandibular disorders, why some of them will progress to becoming chronic patients, and what the appropriate responses may be.

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.

Assessment of somatosensory changes in Chinese temporomandibular disorders arthralgia patients by quantitative sensory testing

BACKGROUND

Somatosensory changes in Chinese temporomandibular disorders (TMD) arthralgia patients have not been fully studied by the latest technologies.

OBJECTIVE

This study aims at assessing somatosensory changes in Chinese TMD arthralgia patients quantitatively.

METHODS

Standardised quantitative sensory testing (QST) was performed on the pain sites and contralateral sites of 40 patients diagnosed with TMD arthralgia according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) before and after medication; similar measures were taken in 40 age- and gender-matched healthy controls. Differences within and between groups were assessed through Z-scores, two-way ANOVA and loss/gain coding system.

RESULTS

The pain sites of patients presented increased sensitivity to thermal stimuli and mechanical pain stimuli together with decreased sensitivity to mechanical tactile stimuli before medication (P < .001). Before treatment, 100% of patients had somatosensory abnormalities at the pain sites; the most frequent abnormalities were somatosensory gain to cold nociceptive, pinprick and pressure stimuli, and the most frequent loss/gain score was L0G3 (no somatosensory loss with a gain of thermal and mechanical somatosensory function; 70.0%). After treatment, although the clinical symptoms and signs of 40 patients disappeared, 80.0% of the patients' pain sites still showed multiple phenotype abnormalities. The most frequent loss/gain score was L0G2 (no somatosensory loss with a gain of mechanical somatosensory function; 35.0%).

CONCLUSIONS

Multiple phenotypes of facial somatosensory abnormalities were detected in Chinese TMD arthralgia patients before and after treatment, despite the disappearance of clinical signs and symptoms. Individual variations indicate a possible need for subgroup classification, individualised management and mechanism-based treatment.

Anterior open bite due to idiopathic condylar resorption during orthodontic retention of a Class II Division 1 malocclusion

A common dilemma when treating anterior open bite is understanding its etiology. Idiopathic condylar resorption (ICR) can cause open bite in affected individuals. Although it is prudent to not treat patients with ICR until active resorption has ceased, orthodontists may begin treating them because anterior open bite from ICR may not appear before or during their orthodontic treatment. This article reports a 12-year-old female who was diagnosed with ICR 10 months after completion of her orthodontic treatment for a Class II Division 1 malocclusion. When a young patient with a high mandibular angle and previous skeletal or dental Class II malocclusion returns with an open bite during the retention phase, the patient's condyles must be carefully examined to determine whether any temporomandibular joint disorder, such as ICR, is present. Currently, the controversy over the cause and the cure for ICR is continuing to challenge orthodontists in diagnoses and treatments. Orthodontists should closely monitor and offer informed treatment options to patients with risk factors for ICR or signs of its pathology that might develop at any stage of orthodontic treatment, including the retention period.

Seeking treatment for temporomandibular disorders: What patients can expect from non-dental health care providers

The dental profession has long been the primary source for clinical management of patients with temporomandibular disorders (TMDs). However, patients with a facial pain problem may seek diagnosis and/or treatment from other health care providers. These providers may be physicians or other professional-level practitioners, or they could be members of various allied groups, such as physical therapists or occupational therapists. However, little has been written about what patients might experience if they seek care outside of the dental profession. This article reports the results of an Internet survey of non-dental professionaland allied health care professionals to learn what they might offer to patients who may be seeking treatment for TMDs. The official organizational websites for all groups, as well as the websites of individual practitioners in each group, were reviewed. Most of the official websites had little or no information about TMDs, but some members of every group surveyed were offering to treat TMDs in their offices. The variety of treatments being offered went far beyond the boundaries of appropriate TMD management in the 21st century. These results are presented with a critical discussion of each concept or practice, as well as advice for both dentists and patients to deal with this situation.

Indexes of jaw muscle function in asymptomatic individuals with different occlusal features

This study aims to assess the correlation between indexes of jaw muscle function and dento-skeletal morphology. A sample of 35 temporomandibular disorders-free healthy individuals (10 males, mean age 26.7 ± 9.8 years) underwent surface electromyographic (sEMG) assessment of bilateral masseter and temporalis muscles, to evaluate sEMG activity during maximum voluntary clenching (MVC) with a dedicated device (Easymyo®, T.F.R. Technology, Udine, Italy). Four outcome parameters were assessed for each individual: MCV on cotton rolls; MVC on teeth; chewing on right and left sides; clench/relax test. Electromyographic recordings were assessed based on five standardized indexes of muscle function, to evaluate the degree of muscle asymmetry during static and dynamic function (i.e., percentage overlapping coefficient [POC], Impact, Asymmetry, Activation, and Torque). For each individual, the presence of a number of occlusal and skeletal features was assessed: asymmetry of molar class; deviated incisor midline; deep bite; open bite; and crossbite. Skeletal class and vertical dimension of occlusion were also evaluated. Based on normality distribution of data, t test and analysis of variance, when needed, were used to compare muscle function indexes between individuals with and without the different dento-skeletal features. None of the muscle function indexes (POC, Impact, Asymmetry, Activation, and Torque) was significantly different between individuals with or without the various dental and skeletal features. Gender differences were also not significant (p > 0.05). Despite some minor differences were observed, none of them was significant. Thus, the interaction between form and function is too complex for hypothesizing a simple one-to-one relationship between interarch tooth relationship and muscle function patterns.

Tratamento para disfunções temporomandibulares: uma revisão sistemática

RESUMO Introdução: A disfunção temporomandibular (DTM) é complexa e multifatorial. São encontrados, na literatura, estudos que comparam diferentes métodos de tratamento. Objetivo: Investigar estudos sobre o tratamento das disfunções temporomandibulares (DTMs) nas diversas áreas da saúde, avaliando a eficácia das técnicas empregadas, principalmente no que se refere ao uso da terapia miofuncional orofacial. Estratégia de pesquisa: Os artigos compilados neste estudo foram selecionados por meio da base de dados PubMed, utilizando os descritores “temporomandibular disorders and oral motor therapy”, “orofacial myofunctional therapy and temporomandibular disorders” e “temporomandibular disorders and myofunctional rehabilitation”. O levantamento realizado limitou-se aos artigos publicado nos idiomas Inglês e Português, entre janeiro de 2006 e dezembro de 2016. Critérios de seleção: Foram incluídos artigos sobre os tratamentos das DTMs associados aos exercícios musculares e/ou terapias manuais. Publicações sem acesso completo, repetidas por sobreposição das palavras-chave, revisões de literatura, cartas ao editor e não relacionadas diretamente ao tema foram excluídas. Resultados: Dos 102 estudos selecionados, 22 atenderam aos critérios estabelecidos. Em geral, a maioria dos tratamentos descritos apresentou efeitos benéficos para pacientes com DTMs. Foi observada grande variabilidade da metodologia adotada para a aplicação e verificação dos efeitos dos tratamentos e somente poucos estudos fizeram uso de grupo controle. Conclusão: Apesar do crescimento no número de pesquisas sobre DTMs, ainda não é possível estabelecer qual a melhor técnica de tratamento. Após análise dos artigos selecionados, observou-se que as técnicas combinadas de terapia (ex.: exercício associado ao uso de equipamento para redução da dor) produzem melhores resultados, com maior redução da dor e melhora da mobilidade mandibular.

Management of pain in patients with temporomandibular disorder (TMD): challenges and solutions

Thanks to advances in neuroscience, biopsychosocial models for diagnostics and treatment (including physical, psychological, and pharmacological therapies) currently have more clinical support and scientific growth. At present, a conservative treatment approach prevails over surgery, given it is less aggressive and usually results in satisfactory clinical outcomes in mild–moderate temporomandibular disorder (TMD). The aim of this review is to evaluate the recent evidence, identify challenges, and propose solutions from a clinical point of view for patients with craniofacial pain and TMD. The treatment we propose is structured in a multi-modal approach based on a biobehavioral approach that includes medical, physiotherapeutic, psychological, and dental treatments. We also propose a new biobehavioral model regarding pain perception and motor behavior for the diagnosis and treatment of patients with painful TMD.

The mechanics of dental occlusion and disclusion

BACKGROUND

The mechanical environment associated with occluding teeth is the foundation for a wide range of research topics, clinical practice and dogma, product development and marketing, and medico-legal issues. The purpose of this study was to experimentally examine the relationships between occlusal factors and their impact on the associated contact forces.

METHODS

Matching pairs of 0°, 20°, 33° and 40° cusp first molar denture teeth were placed into Class I, II and III molar relationships. As the teeth were brought together into occlusion and then separated, the loads experienced by the mandibular tooth were continuously measured by a load cell that was supporting it.

FINDINGS

Loess smoothing splines were fitted to all data curves to calculate 95% confidence intervals. All lateral force magnitudes and directions were statistically different when compared between classes of occlusion, cusp angles, and occlusion vs. disclusion. Noteworthy counterintuitive observations were that the lateral contact force components were generally higher during disclusion than occlusion, the peak lateral force magnitudes did not always occur when the occlusal force was maximum, and the lateral contact force component magnitude can be larger than the occlusal force.

INTERPRETATION

Wedging and friction account for these unexpected results. The data indicate that each occlusion/disclusion cycle is characterized by complex transient loads that may impact wear facet and non-carious cervical lesion formation, implant and restorative failures, various aspects of occlusal trauma, and the concept of axial occlusal loading.

Temporomandibular Disorders and Headache

Temporomandibular disorders (TMD) and primary headaches can be perpetual and debilitating musculoskeletal and neurological disorders. The presence of both can affect up to one-sixth of the population at any one time. Initially, TMDs were thought to be predominantly musculoskeletal disorders, and migraine was thought to be solely a cerebrovascular disorder. The further understanding of their pathophysiology has helped to clarify their clinical presentation. This article focuses on the role of the trigeminal system in associating TMD and migraine. By discussing recent descriptions of prevalence, diagnosis, and treatment of headache and TMD, we will further elucidate this relationship.

Confirming the mechanisms behind cognitive-behavioural therapy effectiveness in chronic pain using structural equation modeling in a sample of patients with temporomandibular disorders

OBJECTIVE

To evaluate whether therapeutic mechanisms assumed to explain the effect of cognitive behavioural therapy (CBT) concerning temporomandibular symptoms are confirmed by structural equation modelling.

METHOD

Patients were randomly assigned to either an experimental group receiving CBT (N = 41) or a standard therapy control group (N = 31). Subjects were assessed before and after intervention using mediator variables hypothesized according to the CBT model, as well as outcome variables and other socio-demographic and clinical measures.

RESULTS

The results confirm that the effect of treatment on pain intensity was partially mediated by distress, catastrophizing, perceived control, distraction, and mental self-control. The self-medication frequency was partially mediated by distraction. Pain interference was partially mediated by distress, distraction, and mental self-control. Reduction in the number of painful points on palpation was partially explained by distress, although in this case, there was a significant direct effect of treatment not mediated by other variables.

CONCLUSIONS

The results could set the principles for the development of more efficient and effective cognitive behavioural interventions for chronic pain.

Informed Consent in Dentistry

A review of literature regarding informed consent in dentistry reveals a paucity of information and minimal scholarship devoted to this subject. But this begs the question about informed consent somehow being different for dentistry than for medicine or other healthcare delivery. My account draws distinctions where appropriate but is rooted in the premise that informed consent is an ethical construct applicable to vulnerable people as patients independent of what type of treatment or body part being considered. This paper highlights the crucial importance of the process of informed consent and refusal in dentistry, underscoring its important place in oral healthcare. This paper will not address the unique circumstances involving consent in those without capacity or focus on informed consent in the research setting; our focus will be on those patients with full decisionmaking capacity in the clinical setting. I will emphasize the importance of disclosure of treatment options and highlight the benefits of shared-decision-making in the informed consent process.

Dental Angle class asymmetry and temporomandibular disorders

OBJECTIVES

The aim of this study was to determine whether there is an association between the presence of asymmetric molar or canine Angle classes on the two sides and the presence of temporomandibular joint dysfunction (TMD).

MATERIALS AND METHODS

Participants to the study were divided into two groups: TMD group (90 patients) or a control group (58 patients). In the TMD group, clinical assessment for TMD was performed according to the Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) guidelines by the same two trained examiners. In both groups, all subjects underwent an assessment of dental occlusion, focusing on the assessment of bilateral canine and molar Angle class relationship. The study protocol was reviewed and approved by the Institutional Review Board of the University of Padova, and each participant gave written consent to take part in the investigation.

RESULTS

TMJ pain was diagnosed in 58, disk displacement in 96, arthrosis in 17, and muscle pain in 46 individuals. Molar Angle class was symmetrical in 86 individuals and asymmetrical in 62 subjects. Molar Angle class was not correlated with any of the TMD diagnoses. Canine Angle class was correlated with TMJ arthrosis. Correlation values with the other TMD diagnoses were low and were not significant.

CONCLUSIONS

It can be suggested that an association between dental Angle class asymmetry and TMDs does not exist and that the role of dental asymmetries as a factor correlated with the presence of TMD signs and symptoms is minimal.

The use of conventional transcutaneous electrical nerve stimulation in chronic facial myalgia patients

OBJECTIVES

The aim of this study was to evaluate the efficacy of conventional TENS in women affected by chronic facial myalgia.

MATERIALS AND METHODS

The study was performed on 49 women affected by chronic facial myalgia randomly allocated in the TENS group (34 women) and the control group (15 women). The subjective level of pain was assessed by the Visual Analogue Scale indicating the mean (VAS MEAN), the maximum (VAS MAX) and the current intensity of pain (VAS NOW). The level of pain at the muscular palpation sites was assessed by the Pericranial Muscle Tenderness Score (PTS) and the Cervical Muscle Tenderness Score (CTS). The TENS therapy lasted for 10 weeks, and data were collected at baseline, after 5, 10, 15 and 25 weeks. The differences between groups before and after treatment were compared with the Mann-Whitney and the Kolmogorov-Smirnov tests. The intra-group differences were compared with the one-way ANOVA test.

RESULTS

The results showed that the VAS MEAN, VAS MAX, PTS and CTS were significantly reduced in the TENS group compared to the control group after 10 weeks of TENS (p < 0.05). The intra-group analysis revealed a decreasing tendency of VAS MEAN, VAS MAX, VAS NOW, PTS and CTS in the TENS group in a 25-week period (p < 0.05).

CONCLUSIONS

The study demonstrated the efficacy of conventional TENS in patients with chronic facial myalgia and the decrease in both subjective and objective pain.

CLINICAL RELEVANCE

Conventional TENS is a safe, non-invasive, easy-to-administer therapy for chronic facial myalgia.

The status of temporomandibular and cervical spine education in credentialed orthopedic manual physical therapy fellowship programs: a comparison of didactic and clinical education exposure

OBJECTIVE

The purpose of this investigation was to establish a baseline of physical therapist education on temporomandibular disorders (TMD)-related topics during credentialed orthopedic manual physical therapy fellowship training and compare it to cervical spine disorders education.

METHOD

An online survey was distributed electronically to each fellowship program credentialed by the American Physical Therapy Association (APTA) and recognized by the Academy of Orthopedic Manual Physical Therapists (AAOMPT). Data were analyzed to compare overall exposure to TMD educational content, including a direct comparison of TMD and cervical spine disorders education.

RESULTS

The response rate was 79%. Thirteen programs (87%) reported providing both didactic and clinical training on both TMD and cervical spine disorders. Didactic education for cervical spine disorders ranged from 16-20 hours to over 25 hours, whereas TMD hours ranged from 0 to 6-10 hours. Clinical education for cervical spine disorders ranged from 11-15 hours to over 25 hours, whereas TMD hours ranged from 0 to 6-10 hours. The number of hours of exposure during didactic training and the number of patients exposed to during clinical training were significantly different when comparing TMD to cervical spine disorders exposure (P<0.0001).

DISCUSSION

The data indicate a lack of uniformity between credentialed fellowship programs in orthopedic manual physical therapy with respect to the extent to which programs expose trainees to evaluation and management of TMD. There is consistency in that all programs provided more training on cervical spine disorders than TMD. Despite a high level of clinical specialization, fellows-in-training receive minimal TMD education.

Treating temporomandibular disorders with permanent mandibular repositioning: is it medically necessary?

In this paper, the authors review the rationale and history of mandibular repositioning procedures in relation to temporomandibular disorders (TMDs) as these procedures have evolved over time. A large body of clinical research evidence shows that most TMDs can and should be managed with conservative treatment protocols that do not include any mandibular repositioning procedures. Although this provides a strong clinical argument for avoiding such procedures, very few reports have discussed the biologic reasons for either accepting or rejecting them. This scientific information could provide a basis for determining whether mandibular repositioning procedures can be defended as being medically necessary. This position paper introduces the biologic concept of homeostasis as it applies to this topic. The continuing adaptability of teeth, muscles, and temporomandibular joints throughout life is described in terms of homeostasis, which leads to the conclusion that each person's current temporomandibular joint position is biologically "correct." Therefore, that position does not need to be changed as part of a TMD treatment protocol. This means that irreversible TMD treatment procedures, such as equilibration, orthodontics, full-mouth reconstruction, and orthognathic surgery, cannot be defended as being medically necessary.

A comparison of expectations and impressions of ethical characteristics of dentists: results of a community primary care survey

BACKGROUND

To better define potential challenges in dental professional ethics, the authors gathered data regarding patients' characterizations of an ideal dentist and compared them with their impressions of dentists in general.

METHODS

The authors invited 500 consecutively seen primary care patients at an academic medical center to participate in the study. Participants completed a 32-item survey assessing key domains of ethical characteristics of health care professionals: trustworthiness, honesty, beneficence, nonmaleficence, respect for autonomy, empathy, compassion, patience, courage, humility and dedication. The authors used the McNemar paired t test to compare respondents' ratings of ideal dentists with their ratings of dentists in general.

RESULTS

Two hundred eight-five patients returned completed surveys, for a response rate of 57 percent. The authors found statistically significant differences between ideal and perceived characteristics in all but one domain. The area of greatest difference related to the domain of trustworthiness (that is, dentists should not "propose unnecessary treatments just so they can make money"). For this survey item, 98 percent of patients reported that it was very or extremely important, but only 57 percent of respondents moderately or strongly agreed that dentists in general were engaging in this practice (P < .0001).

CONCLUSIONS AND PRACTICAL IMPLICATIONS

These data reveal gaps between patients' expectations of the dental profession and their actual impressions of dentists in general. Addressing these discrepancies may be crucial if dentistry is to continue to enjoy the public's trust.

Diagnostic validity (sensitivity and specificity) of panoramic X-rays in osteoarthrosis of the temporomandibular joint

OBJECTIVE

To establish the diagnostic validity of panoramic X-rays (PRx) in temporomandibular osteoarthrosis (OA) using the clinical and imaging criteria (magnetic resonance imaging, MRI) of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) as gold standards.

METHODS

Eighty-four patients with full clinical records (RDC/TMD), PRx, and MRI scans were selected. Two stomatologists evaluated the PRx for OA. The MRI findings were derived from the radiologist report. Intra/inter-examiner concordance was established. The diagnostic concordance between clinical signs and MRI was determined. Both were used as gold standards to calculate the validity of PRx in OA.

RESULTS

The diagnostic validity of PRx with MRI as gold standard was sensitivity=69.0% and specificity=67.9%. The diagnostic validity of PRx with clinical criteria as gold standard was sensitivity=61.6% and specificity=57.9%.

DISCUSSION

Panoramic X-rays have scant diagnostic validity in temporomandibular osteoarthrosis when taking MRI or clinical criteria of RDC/TMD as gold standards.