Magnetic resonance imaging texture analysis of the temporomandibular joint for changes in the articular disc in individuals with migraine headache / Análise de textura por ressonância magnética da articulação temporomanbibular com alterações no disco articular em individuos com cefaleia migranea

Objective: the aim of this study was to analyse the performance of the technique of texture analysis (TA) with magnetic resonance imaging (MRI) scans of temporomandibular joints (TMJs) as a tool for identification of possible changes in individuals with migraine headache (MH) by relating the findings to the presence of internal derangements. Material and Methods: thirty MRI scans of the TMJ were selected for study, of which 15 were from individuals without MH or any other type of headache (control group) and 15 from those diagnosed with migraine. T2-weighted MRI scans of the articular joints taken in closed-mouth position were used for TA. The co-occurrence matrix was used to calculate the texture parameters. Fisher's exact test was used to compare the groups for gender, disc function and disc position, whereas Mann-Whitney's test was used for other parameters. The relationship of TA with disc position and function was assessed by using logistic regression adjusted for side and group. Results: the results indicated that the MRI texture analysis of articular discs in individuals with migraine headache has the potential to determine the behaviour of disc derangements, in which high values of contrast, low values of entropy and their correlation can correspond to displacements and tendency for non-reduction of the disc in these individuals. Conclusion: the TA of articular discs in individuals with MH has the potential to determine the behaviour of disc derangements based on high values of contrast and low values of entropy (AU)

Objetivo: o objetivo deste estudo foi analisar o desempenho da técnica de análise de textura (AT) em exames de ressonância magnética (RM) das articulações temporomandibulares (ATM) como ferramenta para identificação de possíveis alterações em indivíduos com cefaléia migrânea (CM) relacionando os achados com a presença de desarranjos internos. Material e Métodos: trinta exames de RM das ATM foram selecionados para estudo, sendo 15 de indivíduos sem cefaleia migrânea ou qualquer outro tipo de cefaléia (grupo controle) e 15 diagnosticados com CM. As imagens de RM ponderadas em T2 das articulações realizadas na posição de boca fechada foram usadas para AT. A matriz de co-ocorrência foi usada para calcular os parâmetros de textura. O teste exato de Fisher foi usado para comparar os grupos quanto ao sexo, função do disco e posição do disco, enquanto o teste de Mann-Whitney foi usado para os demais parâmetros. A relação da AT com a posição e função do disco foi avaliada por meio de regressão logística ajustada para lado e grupo. Resultados: a AT por RM dos discos articulares em indivíduos com cefaleia migrânea tem o potencial de determinar o comportamento dos desarranjos discais, em que altos valores de contraste, baixos valores de entropia e sua correlação podem corresponder a deslocamentos e tendência a não redução do disco nesses indivíduos. Conclusão: a análise de textura dos discos articulares em indivíduos com CM tem potencial para determinar o comportamento dos desarranjos do disco com base em altos valores de contraste e baixos valores de entropia. (AU)

Discopexia e fisioterapia no tratamento do deslocamento de disco articular sem redução / Discopexy and physiotherapy in the treatment of articular disc displacement withou reduction

A articulação temporomandibular está vunerável a várias condições de anormalidades já bastante conhecidas, dentre elas, o deslocamento do disco articular sem redução, considerado pela literatura o mais comum das patologias desta região. A deterioração do quadro pode ser um indicativo da necessidade cirúrgica. Em específico, no deslocamento de disco sem redução, o reposicionamento definitivo pode ser adquirido através de discopexia e artrocentese. O presente trabalho tem como objetivo relatar um caso clínico de deslocamento de disco articular bilateral sem redução, apresentando a importância da fisioterapia associada à abordagem cirúrgia na recuperação da função mandibular, bem como, reforçar a importância de uma abordagem conjunta entre análise clínica e imaginológica para resolução de casos. Paciente feminino cursando com diversos sintomas em face e pescoço de forma progressiva ao longo de dois anos foi submetida a cirurgia na articulação temporo-mandibular, onde foi feita a discopexia através de ancoragem dos discos articulares com parafusos. A avaliação física, assim como, a imaginológica, ajudaram na confirmação do diagnóstico. A abordagem cirurgica adotada no tratamento deste caso foi descrita na literatura desde o final do século XIX. Conclui-se que, o método utilizado no tratamento do deslocamento de disco sem redução deve ser baseado nos sinais e sintomas do paciente, cuja abordagem deve ser readequada de acordo com as mudanças do quadro apresentado. Nesta análise, a abordagem cirúrgica associada à fisioterapia específica para as estruturas musculoesquelética da face trouxeram resultados positivos(AU)

The temporomandibular joint is responsible for several well-known conditions of abnormalities, among them, the joint disc displacement without reduction, considered by the literature the most common pathology of this region. Deterioration of the condition may be indicative of surgical need. Specifically, in displacement disc without reduction, definitive repositioning can be achieved through discopexy and arthrocentesis. The aim of the present study is to report a case of unilateral articular disc displacement without reduction, as well the importance of physiotherapy associated with the surgical approach in the recovery of mandibular function, as well as reinforcing the importance of a joint approach between clinical and imaging analysis for case resolution. Female patient with several symptoms in the face and neck progressively over two years, underwent surgery in the temporomandibular joint, where discopexy was performed by anchoring the articular discs with screws. The physical assessment, as well as the imaging, helped to confirm the diagnosis. The surgical approach adopted in the treatment of this case has been described in the literature since the end of the 19th century. In conclusion, the method used to treat articular disc displacement without reduction should be based on the patient's signs and symptoms, whose approach should be readjusted according to the changes in the presented picture. In this analysis, the surgical approach associated with specific physiotherapy for the musculoskeletal structures of the face brought positive results(AU)

Efeitos da fotobiomodulação na atividade de nociceptores e na expressão de citocinas pró-inflamatórias após lesão do disco da articulação temporomandibular em ratos / Effects of Photobiomodulation on nociceptive activity and in the expression of inflammatory citokynes after injury of the Temporomandibular Joint disc after in rats

A dor na articulação temporomandibular (ATM) é comum na clínica, na forma de artralgia. Geralmente, é devido a distúrbios do disco articular, deslocamentos ou trauma. Nosso objetivo foi analisar os efeitos da fotobiomodulação (PBM) na atividade nociceptora e na expressão de substâncias pró-inflamatórias no disco da ATM após lesão unilateral em ratos. Foi realizada lesão no disco após acesso cirúrgico na ATM sob anestesia geral. 40 ratos foram divididos em 4 grupos (n = 10 cada): Grupo Op + PBM: Lesão cirúrgica do disco articular e PBM; Grupo SHAM: Falso operado +PBM; Grupo Op: lesão cirúrgica do disco articular; Grupo Naive: controle. Dez sessões foram realizadas com laser GaAs com comprimento de onda de 904 nm e densidade de energia 6J / cm2. Uma parte das amostras contendo tecidos moles articulares foram preparadas para determinação do conteúdo protéico por espectrofotometria da substância P (SP), receptor do potencial transiente vaniloide do subtipo-1 (TRPV-1) e peptídeo relacionado ao gene da calcitonina (CGRP), Interleucina 6 (IL-6), Interleucina 1 beta (IL1-) e Fator de Necrose Tumoral alfa (TNF-). Foi realizada análise de variância de duas vias com pós-teste de Tukey (p <0,050). Outra parte foi utilizada para análise histológica e histomorfometrica. Houve aumento da expressão das substâncias avaliadas após lesão e uma diminuição significante após PBM, quando comparado com os demais grupos. A análise histológica e histomorfométrica mostrou reparação com melhor organização tecidual no grupo Op + PBM O uso da PBM é eficaz na modulação da atividade nociceptora e nas expressões das citocinas pró-inflamatórias na ATM.

Pain in the temporomandibular joint (TMJ) is common in the clinic, in the form of arthralgia. It is usually due to joint disc disorders, dislocations, or trauma. Our objective was to analyze the effects of photobiomodulation (PBM) on nociceptor activity and on the expression of pro-inflammatory substances in the TMJ disc after unilateral injury in rats. Disc injury was performed after surgical access to the TMJ under general anesthesia. 40 rats were divided into 4 groups (n = 10 each): Group Op + PBM: Surgical lesion of the articular disc and PBM; SHAM group: False operated +PBM; Group Op: surgical lesion of the articular disk; Naive group: control. Ten sessions were performed with a GaAs laser with a wavelength of 904 nm and an energy density of 6J/cm2. A portion of the samples containing joint soft tissues were prepared for determination of protein content by spectrophotometry of substance P (SP), receptor transient vanilloid potential subtype-1 (TRPV-1) and calcitonin gene-related peptide (CGRP), Interleukin 6 (IL-6), Interleukin 1 beta (IL1-) and Tumor Necrosis Factor alpha (TNF-). Two-way analysis of variance with Tukey's post-test (p<0.050) was performed. Another part was used for histological and histomorphometric analysis. There was an increase in the expression of the evaluated substances after injury and a significant decrease after PBM, when compared to the other groups. Histological and histomorphometric analysis showed repair with better tissue organization in the Op + PBM group the use of PBM is effective in modulating nociceptor activity and expressions of pro-inflammatory cytokines in the TMJ.

Mini suture anchor: An effective device for reduction and fixation of displaced temporomandibular joint disc with intracapsular condylar fracture / 中华创伤杂志(英文版)

PURPOSE@#The main aim is to provide clinical reference for the application of mini suture anchor in the reduction and fixation of displaced temporomandibular joint (TMJ) disc with intracapsular condylar fracture.@*METHODS@#From October 2018 to October 2019, 21 patients (31 sides) with intracapsular condylar fractures and articular disc displacement from West China Hospital of Stomatology, Sichuan University were included. The selection criteria were: (1) mandibular condylar fractures accompanied by displacement of the TMJ disc, confirmed by clinical examination, CT scan and other auxiliary examinations; (2) indication for surgical treatment; (3) no surgical contraindications; (4) no previous history of surgery in the operative area; (5) no facial nerve injury before the surgery; (6) informed consent to participate in the research program and (7) complete data. Patients without surgical treatment were excluded. The employed patients were followed up at 1, 3, 6 and 12 months after operation. Outcomes were assessed by success rate of operation, TMJ function and radiological examination results at 3 months after operation. Data were expressed as number and percent and analyzed using SPSS 19.0.@*RESULTS@#All the surgical procedures were completed successfully and all the articular discs were firmly attached to the condyles. The articular disc sufficiently covered the condylar head after the fixation. The fixation remained stable when the mandible was moved in each direction by the surgeons. No complications occurred. The functions of the TMJ were well-recovered postoperatively in most cases. CT scan revealed that the screws were completely embedded in the bone without loosening or displacement.@*CONCLUSION@#Mini suture anchor can provide satisfactory stabilization for the reduced articular disc and also promote the recovery of TMJ functions.

Oral behaviors, bruxism, malocclusion and painful temporomandibular joint clicking: is there an association?

Abstract The present cross-sectional case-control study aimed to determine if there is an association between specific oral behaviors, sleep bruxism (SB), awake bruxism (AB), and painful temporomandibular joint (TMJ) clicking. Ninety individuals were dived into three groups; Group 1 (n = 30): painful TMJ clicking; Group 2 (n = 30): painless TMJ clicking; and Group 3 (n = 30): control group. The following clinical data were studied: oral behaviors (unilateral chewing, gum chewing, nail biting, foreign objects biting, leaning with jaw against the hand, and sleeping in a position that pressures the jaw), SB, AB (including the frequency in 10 days, evaluated by ecological momentary assessment), and malocclusions investigated based on clinical inspections (anterior open bite, posterior cross-bite, abnormal overbite/overjet, occlusal guidance, mediotrusive and/or laterotrusive interferences, retruded contact position to maximum intercuspation slide, missing posterior teeth). All statistical tests (Kolmogorov-Smirnov, chi-square, and one-way ANOVA) were performed with a 5% significance level. Group 1 had the highest frequency of and a significant association with leaning with jaw in the hand, sleeping position that pressures the jaw, gum chewing, nail biting, and AB (p<0.05). Gum chewing, nail biting, and AB were associated with Group 2 only when compared to Group 3 (p<0.05). No significant difference among groups was found for other behaviors (unilateral chewing and foreign objects biting), SB, and all malocclusions (p>0.05). It can be concluded that patients with painful TMJ clicking had a higher frequency of and a significant association with some specific harmful behaviors and AB.

Research progress on tissue engineering in repairing tempomandibular joint / 浙江大学学报·医学版

Temporomandibular joint osteoarthritis (TMJOA) is mainly manifested as perforation of temporomandibular joint disc (TMJD) and destruction of condylar osteochondral complex (COCC). In recent years, tissue engineering technology has become one of the effective strategies in repairing this damage. With the development of scaffold material technology, composite scaffolds have become an important means to optimize the performance of scaffolds with the combined advantages of natural materials and synthetic materials. The gelling method with the minimally invasive concept can greatly solve the problems of surgical trauma and material anastomosis, which is beneficial to the clinical transformation of temporomandibular joint tissue engineering. Extracellular matrix scaffolds technology can solve the problem of scaffold source and maximize the simulation of the extracellular environment, which provides an important means for the transformation of temporo joint tissue engineering to animal level. Due to the limitation of the source and amplification of costal chondrocytes, the use of mesenchymal stem cells from different sources has been widely used for temporomandibular joint tissue engineering. The fibrochondral stem cells isolated from surface layer of articular cartilage may provide one more suitable cell source. Transforming growth factor β superfamily, due to its osteochondrogenesis activity has been widely used in tissue engineering, and platelet-rich derivative as a convenient preparation of compound biological factor, gradually get used in temporomandibular joint tissue engineering. With the deepening of research on extracellular microenvironment and mechanical stimulation, mesenchymal stem cells, exosomes and stress stimulation are increasingly being used to regulate the extracellular microenvironment. In the future, the combination of complex bioactive factors and certain stress stimulation may become a trend in the temporomandibular joint tissue engineering research. In this article, the progress on tissue engineering in repairing COCC and TMJD, especially in scaffold materials, seed cells and bioactive factors, are reviewed, so as to provide information for future research design and clinical intervention.

Effect of mesenchymal stem cells on the regeneration of structures associated with temporomandibular joint: narrative review / Efeito de células-tronco mesenquimais na regeneração das estruturas associadas à articulação temporomandibular: revisão narrativa

ABSTRACT BACKGROUND AND OBJECTIVES: Temporomandibular disorders are the problems involving the masticatory muscles and/or the temporomandibular joint and, among them, the bone and joint disc degenerative processes stand out. However, an effective treatment for these cases has not yet been identified in the literature. Thus, the primary objective of this study was to evaluate the reparative potential of mesenchymal stem cells on degenerative changes in structures associated with the temporomandibular joint in humans and animal models. CONTENTS: This narrative review included intervention trials in humans and animals that presented as an outcome variable the repair of joint discs and/or temporomandibular joint. The following databases were used: Pubmed, LILACS, Scielo and Google Scholar. Titles and abstracts were analyzed for the pre-selection of articles potentially eligible for inclusion in this review. The information collected from each article was included in a specific spreadsheet for this purpose containing the year of publication, article title, author's name, study location, type of study, methodology, results, and conclusions. Two human studies and four animal studies were selected to compose the narrative review. In all studies presented, the presence of stem cells was able to improve the clinical, histological, and morphological parameters of the temporomandibular joint. CONCLUSION: The use of stem cells seems to be effective in treating degenerative changes in temporomandibular joint associated structures in both animal and human models. However, due to the small number of studies and their heterogeneity, the results presented should be evaluated sparingly.

RESUMO JUSTIFICATIVA E OBJETIVOS: As desordens temporomandibulares constituem-se em um termo coletivo de problemas que envolvem os músculos mastigatórios e/ou a articulação temporomandibular. Dentre esses, destacam-se os processos degenerativos ósseos e do disco articular, contudo, ainda não foi identificado na literatura um tratamento eficaz para esses casos. Dessa forma, o objetivo desse estudo foi avaliar o potencial reparador das células-tronco mesenquimais sobre as alterações degenerativas das estruturas associadas à articulação temporomandibular em humanos e em modelos animais. CONTEÚDO: Foram incluídos ensaios de intervenção em humanos e em animais que apresentassem como variável desfecho o reparo dos discos articulares e/ou da articulação temporomandibular. Foram realizadas buscas nas seguintes bases de dados: Pubmed, LILACS, Scielo e Google Acadêmico. Os títulos e resumos foram analisados para a pré-seleção dos artigos potencialmente elegíveis para sua inclusão. As informações coletadas de cada artigo foram incluídas em planilha específica para essa finalidade contendo o ano de publicação, título do artigo, nome do autor, local do estudo, tipo de estudo, metodologia, resultado e conclusões. Foram selecionados 2 estudos em humanos e 4 estudos em animais para compor este estudo. Em todas essas pesquisas apresentadas, a presença de células-tronco foi capaz de melhorar parâmetros clínicos, histológicos e morfológicos da articulação temporomandibular. CONCLUSÃO: O uso de células-tronco parece ser eficaz no tratamento das alterações degenerativas das estruturas associadas à articulação temporomandibular. Todavia, devido ao reduzido número de estudos e sua heterogeneidade, os resultados apresentados devem ser avaliados com parcimônia.

Caracterización clínica, imagenológica y quirúrgica de la discopexia en pacientes con artropatía discal de la art iculación temporomandibular. Estudio de serie de casos / Clinical, imagenological and surgical characterization of discopexia in patients with discal arthropathy of the temporomandibular articulation. Case series study

Introducción: El desplazamiento discal es la artropatía temporomandibular más común. Los desplazamientos discales sin Reducción (DDSR) constituyen una condición clínica en la cual en boca cerrada el disco articular se encuentra desplazado completamente, sin contacto con la vertiente anterior de la cabeza mandibular y en boca abierta el disco no es recapturado. El tratamiento quirúrgico realizado es la discopexia. A pesar de toda la información presente en la bibliografía aún existe controversia entre la elección de tratamiento del DDSR. Objetivo: Presentar la experiencia clínica, quirúrgica e imagenológica de la discopexia en DDSR mediante la presentación de una serie de casos. Metodología: Se realizó un estudio retrospectivo de las historias clínicas del Servicio de Cirugía Bucal y Maxilofacial del hospital General del Oeste "Dr. José Gregorio Hernández", Distrito Capital, Venezuela, entre 2014-2018; se seleccionaron seis casos clínicos que presentaban DDSR, los cuales fueron intervenidos con discopexia, posteriormente se evaluaron clínica e imagenológicamente. Resultados: Los seis casos presentaron particularidades en el transcurso del tratamiento desde la fase inicial y en la postoperatoria. Se evidenció una franca mejoría en las manifestaciones clínicas, en contraste, la resonancia magnética postoperatoria, el cual reveló el desplazamiento discal nuevamente. Conclusiones: La estabilidad en la reubicación discal postoperatoria depende de múltiples factores, tales como la estabilidad oclusal, muscular y presencia de hábitos parafuncionales. El aumento en la apertura bucal fue la característica común en todos los pacientes de este estudio así como la disminución de la sintomatología dolorosa.

Introduction: Disc displacement is the most common temporomandibular arthropathy. The displacements without reduction (DDSR) become a clinical practice in the closed mouth the articular disc is completely displaced, without contact with the anterior vertical of the mandibular head and in the open mouth the disc is not recaptured. The surgical treatment performed is discopexy. Despite all the information present in the literature there is still controversy between the choice of treatment of the DDSR. Objective: To present the clinical, surgical and imaging experience of discopexy in DDSR by presenting a series of cases. Methodology: A retrospective study of the clinical records of the Oral and Maxillofacial Surgery Service of the General del Oeste Hospital "Dr. José Gregorio Hernández ", Capital District, Venezuela, between 2014-2018; Six clinical cases were selected that presented DDSR, which were operated on with discopexy, and then evaluated clinically and imaging. Results: The six cases present particularities in the course of the treatment from the initial phase and in the postoperative period. The evidence is improved in the clinical manifestations, in contrast, in the postoperative magnetic resonance, in the articular disc it moved again. Conclusions: Stability in postoperative disc relocation depends on multiple factors, such as occlusal stability, muscle stability and the presence of parafunctional habits. The increase in oral opening was the common feature in all the patients for this study, as well as the decrease in painful symptoms.

Changes in temporomandibular joint anatomy, changes in condylar translation, and their relationship with disc displacement: magnetic resonance imaging study / Ressonância magnética das alterações anatômicas e translação condilar da articulação temporomandibular e suas relações com o deslocamento do disco

Abstract Objective: To assess changes in the articular surfaces of the temporomandibular joint (TMJ) and in condylar translation, as detected by magnetic resonance imaging (MRI), determining whether such changes correlate with disc displacement. Materials and Methods: We retrospectively analyzed the MRI scans of 2076 TMJs of 1038 patients with symptoms of temporomandibular disorder. We attempted to determine whether articular disc deformity and changes in condylar translation, as well as changes in the articular surfaces of the condyle, glenoid fossa, and articular eminence, correlated with disc displacement. Results: Disc displacement with reduction was associated with changes in the shape of the articular eminence. Disc displacement without reduction was most strongly associated with disc deformity, condylar degeneration, glenoid fossa degeneration, and effusion. Neither decreases nor increases in condylar translation were associated with disc deformity, degenerative bone changes, or disc displacement. Conclusion: Changes in the shape of the articular eminence seem to predispose to progression of internal derangement of the TMJ.

Resumo Objetivo: Verificar a correlação entre as alterações das superfícies articulares e da translação condilar com o deslocamento de disco da articulação temporomandibular. Materiais e Métodos: Foram analisados os exames de ressonância magnética de 2076 articulações temporomandibulares de pacientes sintomáticos de desordens temporomandibulares. A deformidade do disco articular, as alterações nas superfícies articulares do côndilo, da fossa glenoide e da eminência articular e as alterações na translação condilar foram correlacionadas com o deslocamento do disco. Resultados: O deslocamento do disco com redução demonstrou associação com as alterações de forma da eminência articular. O deslocamento do disco sem redução apresentou maior associação com a deformidade do disco, degeneração do côndilo e da fossa glenoide e efusão. Diminuição e aumento da translação condilar não apresentaram associação com a deformidade do disco, com alterações ósseas degenerativas, nem com o deslocamento do disco. Conclusão: Mudanças na forma da eminência articular parecem predispor à progressão do desarranjo interno da articulação temporomandibular.

Effects of staurosporine on the contraction of self-assembled constructs of goat temporomandibular joint disc cells / 华西口腔医学杂志

OBJECTIVE@#The effects of the staurosporine on contraction of self-assembled constructs and extracellular matrix syntheses of goat temporomandibular joint discs were investigated.@*METHODS@#Goat temporomandibular joint disc cells were isolated and cultured to P3, and 5.5×10⁶ cells were combined with different concentrations of staurosporine (0, 0.1, 1, 10, 100 nmol·L⁻¹) in agarose wells and cultured for one week. The samples were frozen and sectioned. Safranin-O,  Picro-sirius red and immunohistochemical staining were performed to observe the distributions of the extracellular matrix and the expression of alpha-smooth muscle actin (α-SMA). Enzyme linked immunosorbent assay (ELISA) and Blyscan kits were utilized to quan--titatively detect the contents of type Ⅰ collagen (ColⅠ) and glycosaminoglycans (GAGs).@*RESULTS@#Each group of goat temporo-mandibular joint disc cells in the agarose wells were gathered to self-assemble into a disc-shaped base for 4 hours and then to gradually contract into a round shape. The Picro-sirius red staining was strong and indicated collagen distribution. The Safranin-O staining observed GAGs throughout the entire construct. The expression of ColⅠ was strongly posi-tive in the staurosporine groups; however, the expression of α-SMA was weak. ColⅠ and GAGs contents in the stau-rosporine groups were greater than that of the control group, especially in the 10 nmol·L⁻¹ group (P<0.01).@*CONCLUSIONS@#Staurosporine has a certain effect on the shrinkage of self-assembled constructs; however, such effect is not prominent. Staurosporine contributes to the construction synthesis of extracellular matrix.

Temporomandibular joint disc displacement with reduction: a review of mechanisms and clinical presentation

Abstract Disc displacement with reduction (DDWR) is one of the most common intra-articular disorders of the temporomandibular joint (TMJ). Factors related to the etiology, progression and treatment of such condition is still a subject of discussion. This literature review aimed to address etiology, development, related factors, diagnosis, natural course, and treatment of DDWR. A non-systematic search was conducted within PubMed, Scopus, SciELO, Medline, LILACS and Science Direct using the Medical Subjective Headings (MeSH) terms "temporomandibular disorders", "temporomandibular joint", "disc displacement" and "disc displacement with reduction". No time restriction was applied. Literature reviews, systematic reviews, meta-analysis and clinical trials were included. DDWR is usually asymptomatic and requires no treatment, since the TMJ structures adapt very well and painlessly to different disc positions. Yet, long-term studies have shown the favorable progression of this condition, with no pain and/or jaw locking occurring in most of the patients.

Manejo quirúrgico para los desarreglos internos de la articulación temporomandibular una alternativa con resultados promisorios / Surgical management for internal derangement of the temporomandibular joint an alternative with promising results

Objetivo. Describir las características clínicas y quirúrgicas de un grupo de pacientes con diagnóstico de disfunción de articulación temporomandibular (ATM) llevados a manejo quirúrgico. Diseño del estudio: Se realizó un estudio observacional descriptivo. Materiales y métodos: Se evaluaron las características clínicas y quirúrgicas de un grupo de pacientes con disfunción de ATM llevados a manejo quirúrgico con un periodo de seguimiento de uno y tres meses en el servicio de cirugía maxilofacial del Hospital de San José de Bogotá. Se incluyeron 110 articulaciones a las cuales se les realizó una o varias de las siguientes cirugías: meniscopéxia, eminectomía y condilectomía. Se realizó estadística descriptiva utilizando medidas de tendencia central, de dispersión, frecuencias absolutas y relativas. Resultados. La mayoría de los pacientes con síntomas clínicos tuvieron hallazgos anormales en resonancia magnética. El 90,6% y el 91% de los pacientes presentaron ausencia de dolor y ruido articular respectivamente. De igual forma se evidenció mejoría en la movilidad de la mandíbula. Conclusión. La cirugía para los desarreglos internos de la ATM es una cirugía segura con resultados muy favorables en nuestra población.

Objective: To describe the clinical and surgical characteristics of a group of patients with Temporomandibular joint (TMJ) disorder who underwent surgical intervention. Study design: Descriptive observational study Methods: A group of patients with TMJ disorders who underwent surgical intervention at department of Otolaryngology and Maxillofacial Surgery Hospital de San Jose were evaluated. They were followed during the first and third month post intervention. 110 temporomandibular joints were included. The procedures included one or more of the following: meniscopexy, eminectomy, and/or condilectomy. A descriptive analysis was done using central tendency and dispersion measures, as well as relative and absolute frequencies. Results: A great number of patients with clinical manifestations had abnormal findings in the magnetic resonance (MRI). 90,6% of patients presented pain relief and 91% absence of joint sounds. In addition, there was recovery of the normal mobility of the mandible. Conclusion: Surgical intervention for the internal derangement of the TMJ, is safe and had favorable results in the studied population.

Metrical analysis of disc-condyle relation with different splint treatment positions in patients with TMJ disc displacement

Abstract Objective: To evaluate the effect of bite positions characterizing different splint treatments (anterior repositioning and stabilization splints) on the disc-condyle relation in patients with TMJ disc displacement with reduction (DDwR), using magnetic resonance imaging (MRI). Material and Methods: 37 patients, with a mean age of 18.8±4.3 years (7 male and 30 females) and diagnosed with DDwR based on the RDC/TMD, were recruited. MRI metrical analysis of the spatial changes of the disc/condyle, as well as their relationships, was done in three positions: maximum intercuspation (Position 1), anterior repositioning splint position (Position 2), and stabilization splint position (Position 3). Disc/condyle coordinate measurements and disc condyle angles were determined and compared. Results: In Position 1, the average disc-condyle angle was 53.4° in the 60 joints with DDwR, while it was −13.3° with Position 2 and 30.1° with Position 3. The frequency of successful "disc recapture" with Position 2 was significantly higher (58/60, 96.7%) than Position 3 (20/60, 33.3%). In Positions 2 and 3, the condyle moved forward and downward while the disc moved backward. The movements were, however, more remarkable with Position 2. Conclusions: Anterior repositioning of the mandible improves the spatial relationship between the disc and condyle in patients with DDwR. In addition to anterior and inferior movement of the condyle, transitory posterior movement of the disc also occurred.

Distribution of stress on TMJ disc induced by use of chincup therapy: assessment by the finite element method

ABSTRACT Objective: To assess the distribution of stress produced on TMJ disc by chincup therapy, by means of the finite element method. Methods: a simplified three-dimensional TMJ disc model was developed by using Rhinoceros 3D software, and exported to ANSYS software. A 4.9N load was applied on the inferior surface of the model at inclinations of 30, 40, and 50 degrees to the mandibular plane (GoMe). ANSYS was used to analyze stress distribution on the TMJ disc for the different angulations, by means of finite element method. Results: The results showed that the tensile and compressive stresses concentrations were higher on the inferior surface of the model. More presence of tensile stress was found in the middle-anterior region of the model and its location was not altered in the three directions of load application. There was more presence of compressive stress in the middle and mid-posterior regions, but when a 50o inclined load was applied, concentration in the middle region was prevalent. Tensile and compressive stresses intensities progressively diminished as the load was more vertically applied. Conclusions: stress induced by the chincup therapy is mainly located on the inferior surface of the model. Loads at greater angles to the mandibular plane produced distribution of stresses with lower intensity and a concentration of compressive stresses in the middle region. The simplified three-dimensional model proved useful for assessing the distribution of stresses on the TMJ disc induced by the chincup therapy.

RESUMO Objetivo: avaliar, por meio do método dos elementos finitos, a distribuição das tensões no disco articular produzidas pela mentoneira ortopédica. Métodos: um modelo tridimensional simplificado do disco articular foi desenvolvido com o software Rhinoceros 3D e exportado para o software ANSYS. Uma carga de 4,9 N (500 gf) foi aplicada na superfície inferior do modelo, com inclinação de 30, 40 e 50o em relação ao plano mandibular Gônio-Mentoniano (GoMe). O ANSYS analisou, por meio do método dos elementos finitos, a distribuição das tensões presentes no modelo do disco articular para as diferentes angulações. Resultados: os resultados mostraram que a concentração das tensões de tração e compressão foi maior na superfície inferior do modelo. A tensão de tração foi mais presente na região média-anterior do modelo, e sua localização não se alterou nas três direções da aplicação da carga. A tensão de compressão foi mais presente nas regiões média e média-posterior do modelo, mas quando a carga a 50o foi aplicada, ela se concentrou na região média. As intensidades das tensões de tração e compressão diminuíram progressivamente à medida que a carga foi aplicada mais verticalmente. Conclusão: as tensões induzidas pela mentoneira ortopédica se localizaram principalmente na superfície inferior do modelo. As cargas com maior angulação em relação ao plano mandibular produziram uma distribuição de tensões com menor intensidade e uma concentração da tensão de compressão na região média do modelo. Um modelo tridimensional simplificado se mostrou útil na avaliação da distribuição das tensões no disco articular induzidas pela mentoneira ortopédica.

Effect of Occlusal Splints on the Stress Distribution on the Temporomandibular Joint Disc

Abstract Conservative approach, including occlusal splint therapy, is the first option to treat temporomandibular disorders (TMD), because of its reversibility. The present study analyzed the effect of the articular disc position and occlusal splints use on the stress distribution on this disc. A two-dimensional (2D) finite element (FE) model of the temporomandibular joint with the articular disc at its physiologic position was constructed based on cone-beam computed tomography. Three other FE models were created changing the disc position, according to occlusal splint use and anterior disc displacement condition. Structural stress distribution analysis was performed using Marc-Mentat package. The equivalent von Mises stress was used to compare the study factor. Higher stress concentration was observed on the intermediate to anterior zone of the disc, with maximum values over 2MPa. No relevant difference was verified on the stress distribution and magnitude comparing disc positions and occlusal splint use. However, there was stress reduction arising from the use of the occlusal splints in cases of anterior disc displacement. In conclusion, based on the generated FE models and established boundary conditions, the stress increased at the intermediate zone of the TMJ disc during physiological mandible closure. The stress magnitude was similar in all tested situations

Resumo Abordagens conservadoras, incluindo o uso de placas oclusais, são as primeiras opções de tratamento para disfunção temporomandibular (DTM), devido à sua reversibilidade. O presente estudo analisou o efeito da posição do disco articular e do uso de placa oclusal na distribuição de tensões no disco. Um modelo bidimensional (2D) de articulação temporomandibular (ATM) em posição fisiológica, foi desenvolvido para análise pelo método de elementos finitos, baseado em imagens de tomografia computadorizada do tipo cone-beam. Três outros modelos foram criados alterando a posição do disco de acordo com o uso de placa oclusal e condição de deslocamento anterior do disco. Uma análise estrutural da distribuição de tensões foi realizada no software Marc-Mentat, e equivalente Von Mises foi usado para comparar os fatores em estudo. Maior concentração de tensão foi observada na zona intermediária para a zona anterior do disco, atingindo valores máximos acima de 2 MPa. Nenhuma diferença relevante foi verificada na localização e magnitude das tensões quando comparadas as posições do disco e uso de placa oclusal. No entanto, houve pequena redução das tensões decorrente do uso de placa oclusal em caso de deslocamento anterior do disco. Conclui-se que mediante os modelos criados e condições de contorno estabelecidas, as tensões na zona intermediária do disco aumentam durante o fechamento mandibular fisiológico. A magnitude das tensões foi semelhante em todas as situações testadas

Otomandibular Ligaments: Anatomical Exploration and Clinical Application in Humans.

Ligamentous structures connecting the middle ear and temporomandibular ligament (TMJ) are called as Otomandibular ligaments (OML). Most of the anatomists believed that OML has two parts: malleomandibular ligament (MML) and Discomallear ligament (DML). Both of these ligaments pass through the bony fissure which runs from TMJ to the tympanic cavity, called as Petrotympanic fissure (PTF). Anatomical connection between TMJ and middle ear persists mainly due to continuation of common Meckel’s structure through petro tympanic fissure (PTF). Embryological origin of the MML and DML is debatable but basically, they originates from the first arch. Though they do not play important role in primary movement of TMJ, joint dislocation, anterior disc displacement and hypermobility could happen due to stretching of the DML. MML provides the mechanical support to the head of malleus and forms a movable unit, which acts as suspensory structure for the ossicular chain. Therefore, structural alteration in the MML may plays an important role in affecting middle ear function. The disruption of MML during chronic infection or surgical release of malleus head fixation may affects middle ear sound transmission and results in conductive hearing loss. Shortening of DML by laser coagulation which permits its tightening has been suggested for the treatment of the anterior displacement of the disc. This shortening technique reduces the articular movement range, due to which it was also indicated in the treatment of recurrent temporomandibular dislocations.

MRI study of temporomandibular joint disc position in asymptomatic volunteers / 口腔疾病防治

Objective@#To investigate the position of temporomandibular joint and its relationship with gender and side in asymptomatic volunteers by magnetic resonance imaging (MRI). @*Methods@#The study was based on bilateral MRIs of 30 asymptomatic volunteers, including 15 females and 15 males. A total of 60 temporamandibular joints were scanned oblique-sagittally and oblique-coronarily at mouth closed positions. Classification of the position of temporomandibular joint disc was identified and analyzed according to MRI. @*Results @#Superior disk position was observed in 45 joints (75%), consisting of 20 in female plus 25 in male, and 23 at the right side plus 22 at the left side. Anterior disk position was observed in 7 joints (11.67%), consisting of 5 in female plus 2 in male, and 5 at the right side plus 2 at the left side. Lateral disk position was observed in 6 joints (10%), consisting of 3 in female plus 3 in male, and 2 at the right side plus 4 at the left side. Medial disk position was observed in 2 joints (3.33%), consisting of 0 in female plus 2 in male, and 0 at the right side plus 2 at the left side. No posterior disk position was observed in asymptomatic volunteers. There was no significant difference between genders or sides (P> 0.05). @*Conclusion @#Superior disk positionexists in most of asymptomatic volunteers. Disc displacement also existsin asymptomatic volunteers, however it is not associated with gender and side. Rotational anterolateral positon is the main type of disc displacement in asymptomatic volunteers.

Effect of different oxygen tension on the cytoskeleton remodeling of goat temporomandibular joint disc cells / 华西口腔医学杂志

Objective The effect of different oxygen tensions on the cytoskeleton remodeling of goat temporomandibular joint (TMJ) disc cells were investigated. Methods Goat TMJ disc cells were cultured under normoxia (21% O₂) and hypoxia (2%, 4%, and 8% O₂). Toluidine blue, picrosirius red, and type Ⅰ collagen immunocytochemical staining were performed to observe the changes in cell phenotype under different oxygen levels. Immunofluorescent staining and real-time reverse transcription-polymerase chain reaction analysis were then performed to identify actin, tubulin, and vimentin in the cultured disc cells. Results TMJ disc cells still displayed fibroblast characteristics under different oxygen levels and their cytoskeletons had regular arrangement. The fluorescence intensities of actin and vimentin were lowest at 4% O₂(P<0.05), whereas that of tubulin was highest at 2% O₂ (P<0.05). No significant difference among the other groups was observed (P>0.05). Actin mRNA levels were considerably decreased at 2% O₂ and 4% O₂ in hypoxic conditions, while actin mRNA expression was highest in 21% O₂. Tubulin mRNA levels considerably increased at 2% O₂, while tubulin mRNA expression was lowest in 8% O₂ (P<0.05). Vimentin mRNA expression was lowest at 4% O₂ and highest at 21% O₂, and significant differences were observed between vimentin mRNA expression levels among these oxygen levels (P<0.05). Conclusion Cytoskeletons were reconstructed in different oxygen tensions, and 2% O₂ may be the optimal oxygen level required to proliferate TMJ disc cells.

Manual reduction of articular disc after traumatic extraction of mandibular third molar: a case report

Introduction: Disc displacement without reduction with limited opening is an intracapsular biomechanical disorder involving the condyle-disc complex. With the mouth closed, the disc is in an anterior position in relation to the condylar head and does not reduce with mouth opening. This disorder is associated with persistent limited mandibular opening.Case report:The patient presented severe limitation to fully open the mouth, interfering in her ability to eat. Clinical examination also revealed maximum assisted jaw opening (passive stretch) with less than 40 mm of maximum interincisal opening. Magnetic resonance imaging was the method of choice to identify the temporomandibular disorders.Conclusion: By means of reporting this rare case of anterior disc displacement without reduction with limited opening, after traumatic extraction of a mandibular third molar, in which manual reduction of temporomandibular joint articular disc was performed, it was possible to prove that this technique is effective in the prompt restoration of mandibular movements.

Introdução: o deslocamento do disco articular sem redução com abertura limitada é uma desordem intracapsular que envolve o complexo côndilo-disco. Na posição de boca fechada, o disco articular se encontra numa posição anterior em relação à cabeça da mandíbula e não sofre redução com a abertura de boca. Essa desordem está associada à abertura mandibular limitada e persistente.Caso clínico:o paciente relatava travamento da mandíbula que não permitia uma abertura completa da boca, interferindo, assim, na capacidade de se alimentar. Também era possível observar-se uma abertura assistida (alongamento passivo) com uma distância vertical menor que 40 mm entre os incisivos. A ressonância magnética foi o método de escolha para o diagnóstico das desordens temporomandibulares.Conclusão:por meio da descrição de um caso raro de deslocamento anterior do disco articular sem redução e com abertura limitada, após exodontia traumática do terceiro molar inferior, em que foi realizada a redução manual do disco articular da articulação temporomandibular, provou-se ser essa uma técnica eficaz no rápido restabelecimento dos movimentos mandibulares.

Management of painful temporomandibular joint clicking with different intraoral devices and counseling: a controlled study

Objective The benefit of the use of some intraoral devices in arthrogenous temporomandibular disorders (TMD) patients is still unknown. This study assessed the effectiveness of the partial use of intraoral devices and counseling in the management of patients with disc displacement with reduction (DDWR) and arthralgia.Materials and Methods A total of 60 DDWR and arthralgia patients were randomly divided into three groups: group I (n=20) wore anterior repositioning occlusal splints (ARS); group II (n=20) wore the Nociceptive Trigeminal Inhibition Clenching Suppression System devices (NTI-tss); and group III (n=20) only received counseling for behavioral changes and self-care (the control group). The first two groups also received counseling. Follow-ups were performed after 2 weeks, 6 weeks and 3 months. In these sessions, patients were evaluated by means of a visual analogue scale, pressure pain threshold (PPT) of the temporomandibular joint (TMJ), maximum range of motion and TMJ sounds. Possible adverse effects were also recorded, such as discomfort while using the device and occlusal changes. The results were analyzed with ANOVA, Tukey’s and Fisher Exact Test, with a significance level of 5%.Results Groups I and II showed improvement in pain intensity at the first follow-up. This progress was recorded only after 3 months in Group III. Group II showed an increased in joint sounds frequency. The PPT values, mandibular range of motion and the number of occlusal contacts did not change significantly.Conclusion The simultaneous use of intraoral devices (partial time) plus behavioral modifications seems to produce a more rapid pain improvement in patients with painful DDWR. The use of NTI-tss could increase TMJ sounds. Although intraoral devices with additional counseling should be considered for the management of painful DDWR, dentists should be aware of the possible side effects of the intraoral device’s design.