Changes in jaw and neck muscle coactivation and coordination in patients with chronic painful TMD disk displacement with reduction during chewing.

The treatment of a complex temporomandibular disorder (TMD), such as disk displacement with reduction (DDR) associated with arthralgia and myalgia, may depends on understanding the impairments in muscle function. The aim of this study was to investigate the behavior of the anterior temporalis, masseter and sternocleidomastoid muscles in the time and frequency domains during chewing in patients with chronic painful TMD-DDR using electromyographic (EMG) analysis. Thirty-three patients who met the diagnostic criteria for TMD and 32 volunteers without TMD (control group) underwent clinical examination, chewing pattern classification and EMG analysis. For the EMG analyses, the side of habitual unilateral chewing, as determined by the chewing pattern classification, was selected for recording; in cases of bilateral chewing, the recording side was randomly selected. The EMG-EMG coherence function and EMG-EMG transfer function (gain and phase) values were obtained at the first chewing frequency peak, and the working-side masseter signal was used as a reference in the analyses of the other muscles. Compared to the control group, the TMD group showed a longer chewing stroke duration (P = 0.01) as well as changes in the coactivation and coordination strategies of the jaw muscles, evidenced by greater relative energy expenditure (P< 0.01) and impaired differential recruitment (P< 0.05) and coherence (P< 0.01). Delays in peak and temporal asynchrony occurred in the jaw and neck muscles (P< 0.05). Patients with chronic painful TMD-DDR during chewing presented changes in the jaw and neck muscles, with more compromised function of the former, which are specific to chewing.

Tongue strength, masticatory and swallowing dysfunction in patients with chronic temporomandibular disorder.

BACKGROUND: The possible factors related to functional impairment and limitations in patients with temporomandibular disorders (TMDs) still need to be clarified because recovery of orofacial functions is a goal of their treatment. OBJECTIVE: To investigate whether chronic TMD patients had any changes in tongue strength, besides the difficulty in chewing and orofacial functional impairment, compared to a control group. Moreover, to examine whether tongue strength, chewing difficulties, and orofacial functions were associated. METHODS: Twenty-three patients with chronic TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and volunteers without TMD (control group) were compared. Strength measures were obtained using the Iowa Oral Performance Instrument (IOPI) during tongue protrusion (TPS) and swallowing of saliva (SS) tasks. A scale was used to investigate self-reported chewing difficulties, and the orofacial muscles and functions were evaluated using the orofacial myofunctional evaluation with scores protocol (OMES). RESULTS: Compared to the control group, TMD patients showed reduced TPS and SS, higher difficulty in chewing and worse myofunctional orofacial conditions. Tongue strength was correlated with mastication and swallowing behaviors, as well as with general myofunctional status. Chewing difficulty increased with decreasing tongue strength and with worsening of orofacial muscles and functions. CONCLUSION: Patients with chronic TMD showed reduced tongue strength and worse masticatory and swallowing functions, and these aspects were interrelated. CLINICAL RELEVANCE: The present results contribute additional evidence regarding the impairment of orofacial muscles other than jaw elevator muscles in patients with chronic TMD.

Swallowing changes related to chronic temporomandibular disorders.

OBJECTIVES: To investigate whether chronic temporomandibular disorder (TMD) patients showed any changes in swallowing compared to a control group. Moreover, it was examined whether swallowing variables and a valid clinic measure of orofacial myofunctional status were associated. MATERIAL AND METHODS: Twenty-three patients with chronic TMD, diagnosed with disc displacement with reduction (DDR) and pain, according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), and 27 healthy volunteers (control group) were compared. Surface electromyography (EMG) of the temporalis, masseter, sternocleidomastoid, and suprahyoid muscles was performed during swallowing tasks of thin liquid (10 and 15 mL) and spontaneous saliva. Data were normalized. RESULTS: Compared to the control group, TMD patients showed a prolonged duration of swallowing for liquid and saliva and required a longer time to reach the activity peak and half the integral. While the overall mean value of the relative peaks was similar for the groups, the suprahyoid peak was significantly lower in the TMD group during swallowing of liquid. Moreover, TMD patients recruited the jaw elevator muscles proportionally more than controls. The orofacial myofunctional status was moderately correlated with EMG parameters. CONCLUSION: Patients with chronic TMD showed temporal prolongation and changes in the relative activity of the muscles during the swallowing tasks. CLINICAL RELEVANCE: The present results contribute additional evidence regarding the reorganization of muscle activity in patients with chronic TMD.

Effect of speech-language therapy after low-level laser therapy in patients with TMD: a descriptive study. / Efeito do tratamento fonoaudiológico após a laserterapia de baixa intensidade em pacientes com DTM: estudo descritivo.

Increased pain and/or discomfort during chewing, speaking, and swallowing have been commonly reported by patients with Temporomandibular Dysfunction (TMD). Speech-language pathology therapy (orofacial myofunctional therapy - OMT) has been proposed as part of the treatment for this condition; however, it is a modality that should be introduced when the TMD context and the pain are not accentuated, so that they do not prevent or hinder the performance of exercises. The aim of this study was to analyze the effect of OMT on the treatment of patients with TMD, according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), after analgesia with low-level laser therapy (LLLT), regarding orofacial myofunctional conditions (OMC) and the perception of TMD symptoms. Five patients aged 50 to 61 years were evaluated 30 days after completion of LLLT. An experienced speech-language pathologist conducted, pre- and post-OMT, the application of the ProDTM Multi-questionnaire - to investigate the self-perception of TMD symptomatology, and the Orofacial Myofunctional Evaluation with Scores (OMES) clinical examination - to confirm the orofacial myofunctional conditions. OMC presented increased OMT scores, indicating an increase in myofunctional orofacial balance. According to the patients' perception, TMD signs and symptoms were relieved after the application of OMT. According to the self-perception of the treated patients, introduction of OMT after LLLT analgesia promoted a balance of the orofacial functions of the sample studied, as well as a decrease in the remaining TMD signs and symptoms.

Efeito do tratamento fonoaudiológico após a laserterapia de baixa intensidade em pacientes com DTM: estudo descritivo / Effect of speech-language therapy after low-level laser therapy in patients with TMD: a descriptive study

RESUMO O aumento da dor/desconforto durante atividades como mastigar, falar e deglutir é comumente relatado por pacientes com Disfunção Temporomandibular (DTM) e a terapia fonoaudiológica miofuncional orofacial (TMO) tem sido proposta como parte do tratamento desta condição. Porém é uma modalidade que deve ser instituída quando o quadro de DTM e dor não está exacerbado a fim de não impedir ou dificultar a realização dos exercícios. Objetivo O objetivo deste estudo foi analisar o efeito da TMO no tratamento de pacientes com DTM, segundo o Research Diagnostic Criteria for temporomandibular disorders (RDC/TMD), após analgesia com laserterapia de baixa intensidade (LBI), quanto às condições miofuncionais orofaciais (CMO) e quanto à percepção dos sintomas de DTM. Método Transcorridos 30 dias após a finalização da LBI, cinco pacientes foram avaliados, com idades entre 50 e 61 anos. A aplicação do questionário ProDTMMulti para investigação da autopercepção da sintomatologia de DTM e do exame clínico AMIOFE (Avaliação Miofuncional Orofacial com Escores) para constatação das condições miofuncionais orofaciais foram realizados por fonoaudióloga experiente, antes e após a TMO. Resultados As CMO apresentaram aumento dos escores após TMO, indicando aumento do equilíbrio miofuncional orofacial. De acordo com a percepção das pacientes, após a TMO houve alívio dos sinais e sintomas de DTM. Conclusão A TMO instituída após a analgesia com LBI promoveu equilíbrio das funções orofaciais da amostra estudada e diminuição dos sinais e sintomas de DTM remanescentes, de acordo com a autopercepção dos indivíduos tratados.

ABSTRACT Increased pain and/or discomfort during chewing, speaking, and swallowing have been commonly reported by patients with Temporomandibular Dysfunction (TMD). Speech-language pathology therapy (orofacial myofunctional therapy - OMT) has been proposed as part of the treatment for this condition; however, it is a modality that should be introduced when the TMD context and the pain are not accentuated, so that they do not prevent or hinder the performance of exercises. The aim of this study was to analyze the effect of OMT on the treatment of patients with TMD, according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), after analgesia with low-level laser therapy (LLLT), regarding orofacial myofunctional conditions (OMC) and the perception of TMD symptoms. Five patients aged 50 to 61 years were evaluated 30 days after completion of LLLT. An experienced speech-language pathologist conducted, pre- and post-OMT, the application of the ProDTM Multi-questionnaire - to investigate the self-perception of TMD symptomatology, and the Orofacial Myofunctional Evaluation with Scores (OMES) clinical examination - to confirm the orofacial myofunctional conditions. OMC presented increased OMT scores, indicating an increase in myofunctional orofacial balance. According to the patients' perception, TMD signs and symptoms were relieved after the application of OMT. According to the self-perception of the treated patients, introduction of OMT after LLLT analgesia promoted a balance of the orofacial functions of the sample studied, as well as a decrease in the remaining TMD signs and symptoms.

Effects of oral motor exercises and laser therapy on chronic temporomandibular disorders: a randomized study with follow-up.

This study investigated the efficacy of combining low-level laser therapy (LLLT) with oral motor exercises (OM-exercises) for rehabilitation of patients with chronic temporomandibular disorders (TMDs). Eighty-two patients with chronic TMD and 20 healthy subjects (control group) participated in the study. Patients were randomly assigned to treatment groups: GI (LLLT + OM exercises), GII (orofacial myofunctional therapy-OMT-which contains pain relief strategies and OM-exercises), and GIII (LLLT placebo + OM-exercises) and GIV (LLLT). LLLT (AsGaAl; 780-nm wavelength; average power of 60 mW, 40 s, and 60 ± 1.0 J/cm²) was used to promote analgesia, while OM-exercises were used to reestablish the orofacial functions. Evaluations at baseline (T1), after treatment immediate (T2), and at follow-up (T3) were muscle and joint tenderness to palpation, TMD severity, and orofacial myofunctional status. There was a significant improvement in outcome measures in all treated groups with stability at follow-up (Friedman test, P < 0.05), but GIV did not show difference in orofacial functions after LLLT (P > 0.05). Intergroup comparisons showed that all treated groups had no difference in tenderness to palpation of temporal muscle compared to GC at follow-up (Kruskal-Wallis test, P < 0.01). Moreover, GI, GII, and GIII showed no difference from GC in orofacial functional condition (T2 and T3) while they differed significantly from GIV (P < 0.01). In conclusion, LLLT combined with OM-exercises was more effective in promoting TMD rehabilitation than LLLT alone was. Similar treatment results were verified with the OMT protocol.

Impaired orofacial motor functions on chronic temporomandibular disorders.

Because temporomandibular disorders (TMDs) rehabilitation continues to be a challenge, a more comprehensive picture of the orofacial functions in patients with chronic pain is required. This study assessed the orofacial functions, including surface electromyography (EMG) of dynamic rhythmic activities, in patients with moderate-severe signs and symptoms of chronic TMD. It was hypothesized that orofacial motor control differs between patients with moderate-severe chronic TMD and healthy subjects. Seventy-six subjects (46 with TMD and 30 control) answered questionnaires of severity of TMD and chewing difficulties. Orofacial functions and EMG during chewing were assessed. Standardized EMG indices were obtained by quantitative analysis of the differential EMG signals of the paired masseter and temporal muscles, and used to describe muscular action during chewing. TMD patients showed significant greater difficulty in chewing; worse orofacial scores; longer time for free mastication; a less accurate recruitment of the muscles on the working and balancing sides, reduced symmetrical mastication index (SMI) and increased standardized activity during EMG test than healthy subjects. SMI, TMD severity and orofacial myofunctional scores were correlated (P<0.01). Impaired orofacial functions and increased activity of the muscles of balancing sides during unilateral chewing characterized the altered orofacial motor control in patients with moderate-severe chronic TMD. Implications for rehabilitation are discussed.

Does low intensity laser therapy reduce pain and change orofacial myofunctional conditions?

Due to its multifactorial pain aspects, combined therapies are required for the the comprehensive management of temporomandibular joint disorders (TMD). Interdisciplinary forms of therapies, such as laser therapy, and health care or medical professionals, such as speech therapists, have been proposed for this comprehensive management. The aims of this study were the following: 1. verify whether low-intensity laser therapy would promote significant pain remission; 2. evaluate whether this changes orofacial myofunctional conditions in the sample, as tested, using the Orofacial Myofunctional Evaluation with Scores (OMES); and 3. evaluate whether or not the pain improvement would remain stable after a 30-day follow-up for pain conditions. The study included 12 female volunteers diagnosed with myofascial pain and ages ranging from 18 to 60 years old, with or without intra-articular TMD, according to axis I of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Participants were assessed for pain on palpation, using a visual analogue scale (VAS), before treatment (A1), immediately after 30 days of intervention, i.e, after eight sessions of Low Intensity Laser Therapy (LILT) (A2), and 30 days after the end of the treatment with LILT (A3) (follow-up). Comparing the three evaluation times, it was observed that there was a significant decrease in the values of subjective pain to palpation (p < 0.05). The initial pain (A1) differed significantly from the A2, but did not differ significantly from A3.

Mandibular movement range in children.

BACKGROUND: identification of the mandibular movement range is an important procedure in the evaluation of the stomatognathic system. However, there are few studies in children that focus on normal parameters or abnormalities. AIM: to determine the average range of mandibular movements in Brazilian children aged 6 to 12 years; to verify the difference between genders, in each age group, and between the different age groups: 6-8 years; 8.1-10 years; and 10.1-12 years. METHOD: participants of the study were 240 healthy children selected among regular students from local schools of São Paulo State. The maximum mandibular opening, lateral excursion and protrusive movements, and deviation of the medium line, if present, were measured using a digital caliper. Student T test, Analysis of variance and Tukey test were considered significant for p < 0.05. RESULTS: the mean values observed in the studied sample were: 44.51mm for maximum mandibular opening; 7.71mm for lateral excursion to the right; 7.92mm for lateral excursion to the left; 7.45mm for protrusive movements. No statistical difference was observed between genders. There was a gradual increase in the range of mandibular movements, with significant differences mainly between the ages of 6-8 years and 10.1-12 years. CONCLUSION: during childhood the range of mandibular movements increases. Age should be considered in this analysis for a greater precision in the diagnosis.

Limites de movimentos mandibulares em crianças / Mandibular movement range in children

TEMA: a determinação dos limites de movimentos mandibulares é um importante procedimento na avaliação do estado funcional do sistema estomatognático, porém poucos são os estudos que focalizam os parâmetros de normalidade ou desvios em crianças. Objetivos: definir as médias dos limites de movimentos mandibulares em crianças brasileiras de 6 a 12 anos de idade; verificar diferenças entre os gêneros, em cada faixa etária, e entre as faixas etária de 6 a 8 anos, 8:1 a 10 anos e 10:1 a 12 anos de idade. MÉTODO: participaram 240 crianças, escolares do interior do Estado de São Paulo. Com o auxílio de um paquímetro digital foram mensuradas a máxima abertura mandibular, a protrusão, a excursão lateral direita e esquerda e o desvio da linha média, quando presente. O teste T Student, a Análise de variância e o pós-teste Tukey foram considerados significantes para p < 0,05. RESULTADOS: as médias das medidas da amostra foram: máxima abertura mandibular 44,51 mm, excursão lateral direita 7,71mm, excursão lateral esquerda 7,92 mm e a protrusão 7,45 mm. Não houve diferença estatística entre os gêneros. Houve aumento gradual nos limites dos movimentos mandibulares com o aumento da faixa etária, com diferenças significantes principalmente entre as faixas etárias de 6 - 8 anos e 10:1-12 anos. CONCLUSÃO: durante a infância os limites de movimentos mandibulares aumentam e a idade deve ser considerada na análise desses dados para maior precisão no diagnóstico.

BACKGROUND: identification of the mandibular movement range is an important procedure in the evaluation of the stomatognathic system. However, there are few studies in children that focus on normal parameters or abnormalities. AIM: to determine the average range of mandibular movements in Brazilian children aged 6 to 12 years; to verify the difference between genders, in each age group, and between the different age groups: 6-8 years; 8.1-10 years; and 10.1-12 years. METHOD: participants of the study were 240 healthy children selected among regular students from local schools of São Paulo State. The maximum mandibular opening, lateral excursion and protrusive movements, and deviation of the medium line, if present, were measured using a digital caliper. Student T test, Analysis of variance and Tukey test were considered significant for p < 0.05. RESULTS: the mean values observed in the studied sample were: 44.51mm for maximum mandibular opening; 7.71mm for lateral excursion to the right; 7.92mm for lateral excursion to the left; 7.45mm for protrusive movements. No statistical difference was observed between genders. There was a gradual increase in the range of mandibular movements, with significant differences mainly between the ages of 6-8 years and 10.1-12 years. Conclusion: during childhood the range of mandibular movements increases. Age should be considered in this analysis for a greater precision in the diagnosis.