High prevalence of orofacial pain in juvenile fibromyalgia as detected by a novel tool specifically devised for children and adolescents.

OBJECTIVES: To examine the prevalence of temporomandibular disorders (TMD) in patients with juvenile fibromyalgia syndrome (JFS) and identify TMD characteristics specifically associated to JFS. METHODS: Signs and symptoms of TMD were assessed using a novel clinical tool specifically devised for children that consists of: 1. a self-report multiple-choice questionnaire; 2. a protocol for the clinical examination of the orofacial region. Multivariate logistic regression model was used to identify TMD features associated with JFS. RESULTS: Thirty JFS patients (median age 15.5 years) and 45 healthy controls (median age 15.0 years) were included in this cross-sectional study. Orofacial pain was reported by 26 of 30 JFS patients (86.7%) and by 3 of 45 controls (6.7%; p<0.001). Pain on TMJ palpation was present in 18 of 30 JFS patients (60%) and in 5 of 45 controls (11.1%; p<0.001). Median values of maximum spontaneous mouth opening, voluntary active opening and assisted passive opening were significantly higher in JFS patients than in controls. On multiple regression analysis spontaneous orofacial pain (OR: 21.0; p=0.005), diffuse tenderness on palpation of the masticatory muscles (OR: 14.9; p=0.026) and TMJ hypermobility (OR 1.42; p=0.008) were independently associated with JFS. CONCLUSIONS: The high prevalence of TMD in JFS highlights the need for a broader interdisciplinary evaluation of JFS patients. TMJ hypermobility, in addition to orofacial and masticatory muscle pain, is an important clue for the diagnosis of TMD in adolescents with JFS. Elucidating the link between these disorders will advance individualised management and improve treatment efficacy.

Analysis of the Effect of Exams on Perceived Stress and Temporomandibular Joint Status in Physiotherapy Students: A Pilot Study.

Background and Objectives: Temporomandibular disorders or dysfunction (TMDs) encompass a range of complex conditions that impact the temporomandibular joint (TMJ), chewing muscles, teeth, and/or their supporting tissues. Stress is one of the most associated factors studied as a TMD predictor. The aim is to figure out the influence of stress on TMJ status and salivary cortisol in university students during and before exams. Materials and Methods: The study was non-experimental, employing a longitudinal, analytical, observational cohort design. The study population consisted of students enrolled in the physiotherapy degree program at the Alfonso X El Sabio University (Madrid, Spain). Data were collected during two distinct academic periods: the first period was characterized by low academic stress and no exams, and the second period coincided with the high academic stress of final course exams. The collected results included sociodemographic data, assessment of TMJ status (Fonseca Index), evaluation of muscle evaluation (masseter, upper trapezius, and sternocleidomastoid) using a MOXY Monitor (muscle oxygenation) and Neurotrac® (surface EMG, sEMG), assessment of perceived stress (PSS-14), and measurement of salivary cortisol (enzyme immunoassay with Elisa). The statistical analysis was conducted with a confidence level of 95% (p ≤ 0.05) and asymptotic or bilateral significance. Results: 70 students were analyzed during two different measurement periods. According to the Fonseca Index, initially, 37.14% of the analyzed students showed mild TMDs, 17.14% moderate TMDs, and 45.72% showed no TMDs. In general terms, stress increased with age and is related to female sex, maximum mouth opening decreased with age, oxygen saturation decreased with age and academic stress, and myoglobin concentration was related to age. Furthermore, muscle contraction decreased during higher academic stress and increased with age. For women, age was a risk factor for suffering from TMDs, and stress worsened the transition from having TMDs to having no TMDs in both sexes. Conclusions: Academic stress influences TMJ status and muscle outcomes such as oxygen saturation, myoglobin concentration, and muscle contraction, although more research is needed.

Study of axiography changes in patients with temporomandibular joint dysfunction.

OBJECTIVE: Aim: To determine the effectiveness of treatment of temporomandibular joints muscle and joint dysfunction with occlusive splints based on the analysis of axiography data. PATIENTS AND METHODS: Materials and Methods: 274 (two hundred and seventy-four) patients aged 18 to 44 years with a diagnosis of temporomandibular joints dysfunction before and after treatment. RESULTS: Results: All patients with signs of temporomandibular joints dysfunction before treatment had a violation of the movement trajectory of the lower jaw: deviation - 68.7%, diflexion - 31.3%. When opening and closing the mouth, asymmetric shifts of the lower jaw of more than 2 mm were observed. After treatment with occlusive splints, the correct trajectory of opening and closing the mouth was noted: the number of patients with a trajectory violation decreased by 89.1%, and the amount of displacement of the lower jaw during opening and closing the mouth in 92.4% of patients decreased on average to 0.9 mm. When analyzing the movements of the lower jaw in the sagittal plane, deviations of the trajectory of the lower jaw were found in 79% of clinical cases. After the treatment using occlusive splints, 93.4% of cases of mandibular movement trajectory violations in the transversal plane were eliminated, and 78.1% of patients had a reduction in displacement volume to 0.9 mm. When analyzing the movements of the lower jaw in the sagittal plane, deviations of the trajectory of the lower jaw were found in 79% of clinical cases. After the treatment using occlusive splints, 93.4% of cases of mandibular movement trajectory violations in the transversal plane were eliminated, and 78.1% of patients had a reduction in displacement volume to 0.9 mm. CONCLUSION: Conclusions: Movement trajectories of the lower jaw in the sagittal plane improved in 80.1% of patients, normalization of the position of the lower jaw in relation to the neuromuscular trajectory was achieved in 93.4% of clinical cases. According to the analysis of the parameters, this treatment should be considered effective.

[Internal derangements of the temporomandibular joint]. / Internal derangements van het kaakgewricht.

An internal derangement of the temporomandibular joint is described as a deviation in the position or shape of the joint tissues. Such a change is only functionally manifest if it interferes with smooth movements of the jaw joint. There are a number of internal derangements associated with jaw movements in which popping jaw joint sounds can occur. Examples are an anteriorly or posteriorly displaced disc and hypermobility of the condylar head. Although most internal derangements are harmless and only cause minor discomfort to patients, disc displacements can in some cases develop into a clinical problem, for example when there is a limitation of mouth opening (so-called closed lock) or an inability to close the mouth (so-called open lock). Most patients with these conditions do not require any or only conservative treatment.

Randomized controlled trial of digital therapeutics for temporomandibular disorder: A pilot study.

OBJECTIVES: Temporomandibular disorder (TMD) is a common condition that affects the temporomandibular joint (TMJ) and the muscles of the jaw, resulting in pain and dysfunction. TMD is affected by both behavioral and psychological factors. Digital therapeutics (DTx) can exert therapeutic effects by controlling behavioral factors through the delivery of appropriate interventions. Here, we report an open-label randomized control trial to evaluate the efficacy of DTx for TMD. METHODS: We recruited 40 participants diagnosed with TMD. Participants were randomly divided into an intervention group (DTx use, n = 20) and a control group (n = 20). The intervention group received the usual treatment process for TMD in addition to the use of the DTx. The control group received the usual treatments only. Patients in both groups were followed up for 3-4 weeks, and outcome data were collected and analyzed. RESULT: The intervention group showed a significant reduction in pain scores as measured by the numerical rating scale (NRS) (p = 0.016). Additionally, the intervention group showed a statistically significant increase in maximal mouth opening compared to the control group (p = 0.0079). However, there were no significant differences in improvement in the Jaw Functional Limitation Scale, Oral Behavior Checklist, and Patient Health Questionnaire-4 between the two groups (p = 0503, = 0.820, and = 0.943, respectively). CONCLUSION: This RCT reveals DTx potential in TMD, showing pain and mouth opening improvements with conventional treatment. But no significant changes were noted in other outcomes. The findings advocate for more extensive, long-term research to solidify DTx's role in TMD management. CLINICAL SIGNIFICANCE: This research underlines DTx potential to improve pain outcomes in TMD therapy, reinforcing its value as a complementary treatment modality.

Efficacy of scapulothoracic exercises on proprioception and postural stability in cranio-cervico-mandibular malalignment: A randomized, double-blind, controlled trial.

BACKGROUND: Cranio-cervico-mandibular (CCM) malalignment is associated with forward head posture (FHP) and temporomandibular joint (TMJ) disorders and affects masticatory muscles. OBJECTIVE: This randomized, double-blind controlled trial aimed to compare the efficacy of scapula-thoracic (ST) exercises on temporomandibular and cervical joint position sense and postural stability in individuals with CCM malalignment. METHODS: Fourty-nine participants with CCM malalignment were randomly assigned to the ST exercise group (STEG, n= 24) or the control group (CG, n= 25). STEG included progressive strengthening, proprioceptive, and stabilization exercises. All participants were assessed before treatment, at the end of the 8th week treatment period and at the 12th week post-treatment follow-up. Cranio-vertebral angle measurement, Fonseca's Questionnaire, Helkimo Clinical Dysfunction Index, TMJ position test, cervical joint position error test and postural stability assessment were used. RESULTS: The TMJ and cervical joint position sense, total sway degree, area gap percentage, sway velocity and antero-posterior body sway results showed significant improvement in the STEG compared to the CG (p< 0.05), however medio-lateral body sway did not differ between groups (p> 0.05). CONCLUSIONS: Postural stability, TMJ and cervical joint position sense appear to be affected in individuals with CCM malalignment. Our results showed that an exercise program including ST stabilization, proprioception and strengthening of the scapular muscles may be effective in the management of CCM malalignment and will allow clinicians to plan holistic treatment.

Muscle and joint mechanics during maximum force biting following total temporomandibular joint replacement surgery.

Total temporomandibular joint replacement (TMJR) surgery is the established treatment for severe temporomandibular joint disorders. While TMJR surgery is known to increase mouth-opening capacity, reduce pain and improve quality of life, little is known about post-surgical jaw function during activities of daily living such as biting and chewing. The aim of this study was to use subject-specific 3D bite force measurements to evaluate the magnitude and direction of joint loading in unilateral total TMJR patients and compare these data to those in healthy control subjects. An optoelectronic tracking system was used to measure jaw kinematics while biting a rubber sample for 5 unilateral total TMJR patients and 8 controls. Finite element simulations driven by the measured kinematics were employed to calculate the resultant bite force generated when compressing the rubber between teeth during biting tasks. Subject-specific musculoskeletal models were subsequently used to calculate muscle and TMJ loading. Unilateral total TMJR patients generated a bite force of 249.6 ± 24.4 N and 164.2 ± 62.3 N when biting on the contralateral and ipsilateral molars, respectively. In contrast, controls generated a bite force of 317.1 ± 206.6 N. Unilateral total TMJR patients biting on the contralateral molars had a significantly higher lateral TMJ force direction (median difference: 63.6°, p = 0.028) and a significantly lower ratio of working TMJ force to bite force (median difference: 0.17, p = 0.049) than controls. Results of this study may guide TMJ prosthesis design and evaluation of dental implants.

TET1-mediated epigenetic regulation of tumor necrosis factor-α in trigeminal ganglia contributes to chronic temporomandibular joint pain.

Chronic temporomandibular joint (TMJ) pain profoundly affects patients' quality of life. Trigeminal tumor necrosis factor-α (TNFα) plays a pivotal role in mediating TMJ pain in mice, yet the underlying epigenetic mechanisms remain enigmatic. To unravel these epigenetic intricacies, we employed a multifaceted approach. Hydroxymethylated DNA immunoprecipitation (hMeDIP) and chromatin immunoprecipitation (ChIP) followed by qPCR were employed to investigate the demethylation of TNFα gene (Tnfa) and its regulation by ten-eleven translocation methylcytosine dioxygenase 1 (TET1) in a chronic TMJ pain mouse model. The global levels of 5-hydroxymethylcytosine (5hmc) and percentage of 5hmc at the Tnfa promoter region were measured in the trigeminal ganglia (TG) and spinal trigeminal nucleus caudalis (Sp5C) following complete Freund's adjuvant (CFA) or saline treatment. TET1 knockdown and pain behavioral testing were conducted to ascertain the role of TET1-mediated epigenetic regulation of TNFα in the pathogenesis of chronic TMJ pain. Our finding revealed an increase in 5hmc at the Tnfa promoter region in both TG and Sp5C of CFA-treated mice. TET1 was upregulated in the mouse TG, and the ChIP result showed TET1 direct binding to the Tnfa promoter, with higher efficiency in the CFA-treated group. Immunofluorescence revealed the predominant expression of TET1 in trigeminal neurons. TET1 knockdown in the TG significantly reversed CFA-induced TNFα upregulation and alleviated chronic TMJ pain. In conclusion, our study implicates TET1 as a vital epigenetic regulator contributing to chronic inflammatory TMJ pain via trigeminal TNFα signaling. Targeting TET1 holds promise for epigenetic interventions in TMJ pain management.

Consecuencias de la artritis reumatoide en la articulación temporomandibular y su manejo odontológico / Consequences of rheumatoid arthritis in the temporomandibular joint and its dental management

Introducción: la artritis reumatoide es parte del grupo de las enfermedades autoinmunes con incidencia considerable sobre la población. Se caracteriza por la afección de las articulaciones del cuerpo que la padece; en mayor frecuencia se encuentra afectada la articulación temporomandibular por el complejo articular que ésta presenta; entre los signos y síntomas que comúnmente podemos encontrar en pacientes con este tipo de enfermedad son los chasquidos o ruidos articulares, dolor orofacial, pérdida o imposibilidad del movimiento de la mandíbula y cambios anatómicos localizados en el área de la articulación temporomandibular. Objetivo: describir las consecuencias que desencadena la artritis reumatoide sobre la articulación temporomandibular y cómo es para el odontólogo el manejo de estos pacientes en consulta, evaluar los tratamientos para cada caso sobre un correcto diagnóstico. Material y métodos: se realizó una revisión bibliográfica de artículos recientes sobre el tema, utilizando buscadores como SciELO, Elsevier y PubMed, siendo 30 las fuentes seleccionadas con idiomas en inglés y español. Resultados: esta enfermedad autoinmune se caracteriza por afectar múltiples articulaciones del cuerpo humano simétrica y bilateralmente incluyendo la articulación temporomandibular (ATM), lo cual conlleva al riesgo de desarrollar trastornos temporomandibulares (TTM). Es importante conocer los métodos para realizar un correcto diagnóstico oportuno de la ATM del paciente con artritis reumatoide (AR) con la finalidad de ofrecer un tratamiento conservador. Conclusión: los trastornos temporomandibulares desencadenantes de la artritis reumatoide son afecciones que se deben considerar para el buen manejo del paciente con este padecimiento, comprender y respaldar un diagnóstico clínico es de vital importancia para dar al paciente un tratamiento adecuado dependiendo el grado de complejidad en la que cada individuo se encuentra; conocer el manejo adecuado y encaminar al paciente a una mejor calidad de vida es clave en la consulta odontológica del día a día (AU)

Introduction: rheumatoid arthritis is part of the group of autoimmune diseases with considerable incidence in the population. It is characterized by the affection of the joints of the body that suffers from it; most frequently the temporomandibular joint is affected due to the articular complex that it presents; among the signs and symptoms that we can commonly find in patients with this type of disease are joint clicks or noises, orofacial pain, loss or impossibility of jaw movement and anatomical changes located in the temporomandibular joint area. Objective: to describe the consequences that rheumatoid arthritis triggers on the temporomandibular joint and how it is for the dentist to manage these patients in consultation, to evaluate the treatments for each case on a correct diagnosis. Material and methods: a bibliographic review of recent articles on the subject was carried out, using search engines such as SciELO, Elsevier and PubMed, with 30 sources selected in English and Spanish. Results: this autoimmune disease is characterized by affecting multiple joints of the human body symmetrical and bilaterally including the TMJ which leads to the risk of developing TMD. It is important to know the methods to make a correct diagnosis of the TMJ of the patient with RA in order to offer a conservative treatment. Conclusions: the temporomandibular disorders that trigger rheumatoid arthritis are conditions that should be considered for the proper management of the patient with this condition, understanding and supporting a clinical diagnosis is of vital importance to give the patient an adequate treatment depending on the degree of complexity in which each individual is; knowing the proper management and directing the patient to a better quality of life is key in the day-to-day dental practice (AU)

GLX351322, a Novel NADPH Oxidase 4 Inhibitor, Attenuates TMJ Osteoarthritis by Inhibiting the ROS/MAPK/NF-κB Signaling Pathways.

As a degenerative disease in joints, temporomandibular joint osteoarthritis (TMJOA) is characterized by progressive cartilage degradation, subchondral bone remodeling, and chronic synovitis, severely undermining functions and quality of life in patients. NADPH oxidase 4 (NOX4) contributes to reactive oxygen species (ROS) production and inflammatory pathway activation in osteoarthritis, which has attracted increasing attention in research in recent years. GLX351322 (GLX), a novel NOX4 inhibitor, exerts a protective effect on chondrocytes. However, whether it has a therapeutic effect on ROS production and inflammatory responses in synovial macrophages remains to be evaluated. In this study, we examined the effect of GLX on LPS-induced ROS production and inflammatory responses in vitro and on complete Freund's adjuvant (CFA)-induced TMJ inflammation in vivo. We found that GLX could depress LPS-induced intracellular ROS production and inflammatory response without cytotoxicity by inhibiting the ROS/MAPK/NF-κB signaling pathways. In line with in vitro observations, GLX markedly attenuated the synovial inflammatory reaction in the TMJ, thus protecting the condylar structure from severe damage. Taken together, our results suggest that GLX intervention or NOX4 inhibition is a promising curative strategy for TMJOA and other inflammatory diseases.

The effect of association of aspirin and omega 3 in rat temporomandibular joint with induced arthritis.

This study aimed to evaluate the effects of omega-3 (ω3) polyunsaturated fatty acids, in association with aspirin (AA), on the morphology of cytokine release in the temporomandibular joint (TMJ) of rats induced with rheumatoid arthritis (IR) by injecting 100 µL of complete Freund's adjuvant with bovine type II collagen at the tail base. Thirty-two adult male rats were divided into treatment groups: Sham, treated with 0.9% sodium chloride (NaCl) p.o.; IR-control, treated with 0.9% NaCl p.o.; IR-ω3 treated with ω3 PUFAS (85 mg/kg/day p.o.); and IR-ω3 + AA treated with ω3 (85 mg/kg/day p.o.) + AA (20 mg/kg/day i.p.). After maintained treatment for seven days, the animals were euthanized. Bilateral TMJs from each rat were removed and one was subjected to histological immunoassays and enzyme-linked immunosorbent assays to assess interleukin (IL)-1ß, tumor necrosis factor-α, and IL-10 levels. Data analysis was performed using the Kruskal-Wallis and Dunn tests. In the IR-ω3 and IR-ω3 + AA groups, the TMJ was greater than in the IR-control group (P < 0.0001). The addition of AA did not improve the effects of ω3 (P = 0.0698). Similarly, the addition of AA conferred no additional effects on the cytokine levels (P > 0.05); however, it increased the proteoglycan density, compared with ω3 alone. We found that ω3 exhibited anti-inflammatory activity in arthritic rats, and the addition of AA increased proteoglycan density, but did not affect cytokine expression.

Relación entre contactos mediotrusivos con la articulación temporomandibular y la oclusión / Relationship between mediotrusive contacs, the temporomandibular joint and occlusion

Los contactos mediotrusivos son aquellos contactos oclusales que se encuentran entre las vertientes in- ternas de las cúspides linguales maxilares y las inter- nas de las cúspides bucales mandibulares del lado de no trabajo durante los movimientos de lateralidad. Estos contactos mediotrusivos podría desencadenar trastornos temporomandibulares, afectando la oclu- sión y la articulación temporomandibular. El objetivo de este estudio es analizar las caracterís- ticas y la relación entre los contactos mediotrusivos con la articulación temporomandibular y la oclusión en pacientes que consultan al Servicio de Oclusión y ATM del Hospital Odontológico de la Facultad de Odontología de la Universidad Nacional del Nordeste (AU)

Mediotrusive contacts are those occlusal contacts that are found between the internal slopes of the maxillary lingual cusps and the internal slopes of the mandibular buccal cusps on the non-working side during laterality movements. These mediotrusive contacts could trigger temporomandibular disorders affecting occlusion and temporomandibular joint. The objective of this study was to analyze the characteristics and relationship of mediotrusive contacts with occlusion and the temporomandibular joint, in patients who consult the Occlusion and TMJ Service of the Dental Hospital of the Faculty of Dentistry of the National University of the Northeast (AU)

Impact of Cervical Spine Rehabilitation on Temporomandibular Joint Functioning in Patients with Idiopathic Neck Pain.

OBJECTIVE: The aim of this study was to assess the effectiveness of a 3-week rehabilitation programme focusing only on the cervical region, pain intensity, range of motion in the cervical spine, head posture, and temporomandibular joint (TMJ) functioning in subjects with idiopathic neck pain who did not report TMJ pain. DESIGN: A parallel group trial with follow-up. METHODS: The study included 60 participants divided into 2 groups: experimental: n = 25, 27-57 years old, experiencing idiopathic neck pain and who underwent a 3-week rehabilitation programme, and the control, n = 35, 27-47 years, who were cervical pain-free. At baseline and after 3 weeks of treatment in the experimental group and with a 3-week time interval in the control group, pain intensity, head posture in the sagittal plane, range of motion in the cervical spine, and TMJ functioning were evaluated. RESULTS: After 3 weeks of rehabilitation, there was a significant decrease in pain intensity, improved range of motion of the cervical spine and head posture, and improved clinical condition of TMJ in participants with idiopathic neck pain who did not report TMJ pain. CONCLUSION: The study suggested that idiopathic neck pain is associated with limited range of motion in the cervical spine, incorrect head posture, and TMJ dysfunction. Our data suggests that therapy focusing only on the cervical region may improve the clinical condition of the TMJ in subjects with idiopathic neck pain who do not report TMJ pain. These observations could be helpful in physiotherapeutic treatment of neck and craniofacial area dysfunctions. This trial is registered with ISRCTN Registry ISRCTN14511735.

Alterações posturais associadas a distúrbios respiratórios e sua correlação com as desordens temporomandibulares: uma revisão de literatura / Postural changes associated with respiratory disorders and their correlation with temporomandibular disorders: a literature review

Objetivo: a presente revisão almeja fornecer à prática clínico-odontológica e ao meio científico uma compreensão atualizada acerca da correlação entre as alterações posturais geradas pela presença de distúrbios respiratórios e as desordens temporomandibulares (DTMs). Revisão de literatura: foi realizada uma busca entre o período de 2005 a 2021 nas seguintes bases de dados: Medline (via PubMed), Portal de Periódicos Capes e Scopus, utilizando-se dos termos "temporomandibular joint; temporomandibular disorders; posture control; postural control; breathing". Como resultado, foram encontrados 4.384 documentos, que foram analisados por títulos, resumos, texto completo e critérios de elegibilidade, até se chegar ao total de 5 estudos a serem incluídos nesta revisão. Considerações finais: os principais fatores observados foram a associação das DTMs com condições como padrão de respiração do tipo bucal, postura anterior da cabeça, hiperatividade de músculos acessórios da respiração, rotação posterior da mandíbula e apneia obstrutiva do sono. Os estudos ressaltaram a necessidade da abordagem completa desses pacientes, visto que os papéis dos distúrbios respiratórios e das alterações posturais podem representar desafios no diagnóstico e no tratamento das DTMs.(AU)

Objective: this review aims to provide to the clinical dental practice and the scientific community an updated understanding of the correlation between postural changes generated by the presence of respiratory disorders and temporomandibular joint disorders (TMD). Literature review: a search was carried out covering the period from 2005 to 2021 in the following databases: Medline (via PubMed), Portal de Periódicos Capes and Scopus using the terms temporomandibular joint; temporomandibular disorders; posture control; postural control; breathing. As a result, 4,384 documents were obtained and shortlisted by title, abstracts, full text and eligibility criteria, resulting in the five studies included in this review. Final considerations: the main factors observed were the association of TMD with conditions as mouth breathing, anterior head posture, hyperactivity of accessory breathing muscles, posterior rotation of the jaw and obstructive sleep apnea. The studies underscored the need for a complete approach to these patients, given that the role of respiratory disorders and postural changes may represent a challenge in the diagnosis and treatment of TMD.(AU)

Mandibular range of motion in children with juvenile idiopathic arthritis with and without clinically established temporomandibular joint involvement and in healthy children; a cross-sectional study.

BACKGROUND: Recognition of temporomandibular joint (TMJ) involvement in children with juvenile idiopathic arthritis (JIA) has gained increasing attention in the past decade. The clinical assessment of mandibular range of motion characteristics is part of the recommended variables to detect TMJ involvement in children with JIA. The aim of this study was to explore explanatory variables for mandibular range of motion outcomes in children with JIA, with and without clinically established TMJ involvement, and in healthy children. METHODS: This cross-sectional study included children with JIA and healthy children of age 6-18 years. Mandibular range of motion variables included active and passive maximum interincisal opening (AMIO and PMIO), protrusion, laterotrusion, dental midline shift in AMIO and in protrusion. Additionally, the TMJ screening protocol and palpation pain were assessed. Adjusted linear regression analyses of AMIO, PMIO, protrusion, and laterotrusion were performed to evaluate the explanatory factors. Two adjusted models were constructed: model 1 to compare children with JIA and healthy children, and model 2 to compare children with JIA with and without TMJ involvement. RESULTS: A total of 298 children with JIA and 169 healthy children were included. Length was an explanatory variable for the mandibular range of motion excursions. Each centimeter increase in length increased AMIO (0.14 mm), PMIO (0.14 mm), and protrusion (0.02 mm). Male gender increased AMIO by 1.35 mm. Having JIA negatively influenced AMIO (3.57 mm), PMIO (3.71 mm), and protrusion (1.03 mm) compared with healthy children, while the discrepancy between left and right laterotrusion raised 0.68 mm. Children with JIA and TMJ involvement had a 8.27 mm lower AMIO, 7.68 mm lower PMIO and 0.96 mm higher discrepancy in left and right laterotrusion compared to healthy children. CONCLUSION: All mandibular range of motion items were restricted in children with JIA compared with healthy children. In children with JIA and TMJ involvement, AMIO, PMIO and the discrepancy between left and right laterotrusion were impaired more severely. The limitation in protrusion and laterotrusion was hardly clinically relevant. Overall, AMIO is the mandibular range of motion variable with the highest restriction (in millimeters) in children with JIA and clinically established TMJ involvement compared to healthy children.

Predisposing conditions for condylar sag after intraoral vertical ramus osteotomy.

Intraoral vertical ramus osteotomy (IVRO) is used to treat mandibular prognathism and temporomandibular disorders. However, the improvement of temporomandibular disorders after IVRO is considered to be due to the anterior and downward movement of the mandibular condyle, which may lead to condylar sag, and in the worst case, condylar luxation. In this retrospective cohort study, we examined factors potentially associated with condylar sag. Univariate analysis indicated that condylar sag was significantly associated with the following factors: magnitude of setback (P = 0.001), less than 3 mm setback (P < 0.001), presence of temporomandibular joint (TMJ) symptoms (P = 0.002), Wilkes classification (P = 0.039), occlusal cant correction ≥ 2 mm (P = 0.018), and mandibular condyle deformation (P < 0.001). Setback magnitude (P = 0.032) and TMJ symptoms (P = 0.007) remained significant in the multivariate analysis. In the receiver operating characteristic curve, the setback magnitude cut-off value for condylar sag after IVRO was 3.25 mm. Thus, the incidence of condylar sag after IVRO is increased with a smaller setback magnitude (≤ 3.25 mm) and the presence of TMJ symptoms. These factors should be evaluated by surgeons during treatment planning for IVRO to estimate condylar sag, and it may be possible to predict the risk of condylar luxation.

Análisis de las creencias limitantes a través del acompañamiento en Bioneuroemoción(R) de individuos con diagnóstico de bruxismo / Analysis of limiting beliefs through the accompainment in Bioneuroemotion(R) in individuals with a diagnosis of bruxism

El propósito de este trabajo cualtitativo fue aplicar el método de Bioneuroemoción en individuos que, estando en tratamiento por bruxismo, continuaban con dolor y sintomatología asociada. El análisis de las creencias limitantes en común de los individuos, las resonancias familiares y la emoción primaria desencadenada, permitieron obtener desde dónde percibían dichos individuos las situaciones de mayor estrés. Para ello, se consideró un diseño muestral centrado en un grupo de cinco pacientes que concurrían al Servicio de ATM (Articulación Temporomandibular) de un hospital odontológico de la Ciudad de Buenos Aires, donde estaban siendo tratados por bruxismo con placas miorrelajantes (AU)

Mechanical Stress Induce PG-E2 in Murine Synovial Fibroblasts Originating from the Temporomandibular Joint.

Genetic predisposition, traumatic events, or excessive mechanical exposure provoke arthritic changes in the temporomandibular joint (TMJ). We analysed the impact of mechanical stress that might be involved in the development and progression of TMJ osteoarthritis (OA) on murine synovial fibroblasts (SFs) of temporomandibular origin. SFs were subjected to different protocols of mechanical stress, either to a high-frequency tensile strain for 4 h or to a tensile strain of varying magnitude for 48 h. The TMJ OA induction was evaluated based on the gene and protein secretion of inflammatory factors (Icam-1, Cxcl-1, Cxcl-2, Il-1ß, Il-1ra, Il-6, Ptgs-2, PG-E2), subchondral bone remodelling (Rankl, Opg), and extracellular matrix components (Col1a2, Has-1, collagen and hyaluronic acid deposition) using RT-qPCR, ELISA, and HPLC. A short high-frequency tensile strain had only minor effects on inflammatory factors and no effects on the subchondral bone remodelling induction or matrix constituent production. A prolonged tensile strain of moderate and advanced magnitude increased the expression of inflammatory factors. An advanced tensile strain enhanced the Ptgs-2 and PG-E2 expression, while the expression of further inflammatory factors were decreased. The tensile strain protocols had no effects on the RANKL/OPG expression, while the advanced tensile strain significantly reduced the deposition of matrix constituent contents of collagen and hyaluronic acid. The data indicates that the application of prolonged advanced mechanical stress on SFs promote PG-E2 protein secretion, while the deposition of extracellular matrix components is decreased.

Morfología y Fisiopatología del Fibrocartílago de la ATM. Revisión sistemática / Morphology and Pathophysiology of the TMJ Fibrocartilage. Systemic review

RESUMEN: El objetivo: del presente estudio fue efectuar una revisión actualizada de la morfología, fisiopatología y aspectos moleculares de la capa fibrocartilaginosa de las ATM en humanos. Método: se realizó búsqueda electrónica y manual con los términos MeSH "TMJ" y "fibrocartilage", sin límite de fecha o idioma. Los desenlaces definidos fueron: morfología del fibrocartílago, fisiopatología del fibrocartílago articular, modeladores moleculares del fibrocartílago y deterioro del fibrocartílago. Resultados: Se identificaron 1.071 títulos de artículos que después de las exclusiones, fueron seleccionados 16 a texto completo para la revisión. El fibrocartílago (FC) que cubre las superficies de las ATM es un tejido crítico en el establecimiento y la tasa de progresión de las alteraciones óseas degenerativas, clínicamente sus discontinuidades se asocian a patologías que provocan dolor, ruidos y limitación funcional. Conclusiones: A pesar de la diversidad metodológica, heterogeneidad de objetivos y diferentes características de los estudios incluidos en la revisión, el fibrocartílago de la ATM, como tejido avascular, determina fisiología de baja capacidad reparativa y mayor frecuencia de patología del FC en mujeres en edad fértil, asociado a receptores hormonales. La fisiopatología muestra reacciones inmunitarias que incrementan la acción de MMPs, interleucinas y FNTα, responsables de la degradación de la matriz extracelular, destrucción celular y morfológica del fibrocartílago, que conducen a sintomatología inflamatoria y degenerativa de pacientes que presentan artralgias y sinovitis en las ATM.

ABSTRACT: The aim: of the present study was to carry out an updated review of the morphology, physiopathology and molecular aspects of the TMJ fibrocartilage in humans. Method: electronic/manual search was performed with the MeSH terms "TMJ" and "fibrocartilage", with no date or language limit. The defined outcomes were: morphology of the fibrocartilage, physiopathology of the articular fibrocartilage, fibrocartilage molecular modelers and fibrocartilage deterioration. Results: 1071 articles were identified and after exclusions, 16 full-texts were selected for review. The fibrocartilage (FC) that covers the surfaces of the TMJ is a critical tissue in the establishment and progression rate of degenerative bone diseases; clinically, its discontinuities are associated with pain, noise and functional limitation. Conclusions: In spite of the methodological diversity, heterogeneity of objectives and different characteristics of the patients included in the review, TMJ fibrocartilage, as avascular tissue, determines a physiology of low reparative capacity, observed with greater frequency of FC damage in women of fertile age, associated with a greater amount of hormonal receptors. The physiopathology shows that the immune reactions increase some MMPs, interleukins and FNTα, which are linked to the degradation of the extracellular matrix, FC cellular and morphological destruction and define the inflammatory and degenerative symptomatology of patients who present TMJ arthralgia´s and synovitis.

Recommended Management of Temporomandibular Joint Dislocation During the COVID-19 Outbreak.

The epidemic of coronavirus disease 2019 (COVID-19) has become a major public health disaster worldwide. From January 23 to March 20, total 17 patients with TMJ dislocation were treated in dental emergency department in School and Hospital of Stomatology, Wuhan University. Almost half of the patients are older than 80 years of age and they have recurrent joint dislocations. They are also at high risk for the COVID-19. The supine position technique method is suggested. The authors consider it necessary to recommend a practical management for TMJ dislocation.