DMDDuchenne muscular dystrophy LSCM Left sternocleidomastoid muscle RSCM Right sternocleidomastoid muscle AIM This study aimed to analyse electromyographic activity, masticatory efficiency, muscle thickness, and bite force of individuals with Duchenne muscular dystrophy (DMD).METHOD Forty males aged 4-15 years, 20 with DMD and 20 healthy age-, height-, and weight-matched controls, underwent electromyography and ultrasonography of temporalis, masseter, and sternocleidomastoid muscles during postural control of the jaw, mastication, and maximal molar bite force. RESULTSThe normalized electromyography signals showed higher activity in masseter and temporal muscles at rest, during protrusion, left and right laterality, and fatigue condition in the group with DMD than in the comparison group (p≤0.05). For masticatory efficiency of cycles, in analysis of non-habitual chewing of flavourless gum, and habitual chewing of peanuts and raisins, the group with DMD presented lower averages (p≤0.05). For the muscle thickness, the results showed that there was a lower muscle thickness in the group with DMD for all muscles during the rest and maximal voluntary contraction, except for masseter and sternocleidomastoid in the maximal voluntary contraction. In the maximal molar bite force, the group with DMD presented higher values for both sides than the comparison group (p≤0.05).INTERPRETATION Patients with DMD show muscle changes related to the stomatognathic system, in their activity, bite force, and muscle thickness.Duchenne muscular dystrophy (DMD) is an X-linked lethal neuromuscular disease that affects males. 1,2 Necrosis of skeletal muscle fibres, muscle fibrosis, and the infiltration of adipose tissue are seen from infancy. 3,4 Diagnosis is based on clinical presentation associated with a DNA diagnosis, significant elevations in the serum creatine kinase levels, morphological changes in the affected muscles, and the absence of the protein dystrophin. 5,6 The primary consequence of DMD is the decline of muscle function. Surface electromyography (EMG) has great potential as a measurement instrument in assessing muscle biomechanics.7 Quantitative EMG data can provide information on disease severity in various muscular dysfunctions. 8 The concomitant use of ultrasonography allows for the observation of changes in the muscle architecture, with the substitution of muscle cells by fat and connective tissue. The purpose of this study was to use surface EMG to detect changes in the patterns of EMG signals in patients with DMD to assess the activity of their temporalis, masseter, and sternocleidomastoid muscles bilaterally, and to analyse the masticatory efficiency, maximal molar bite force, and ultrasonography to evaluate muscle thickness of these muscles.These methods of analysis allow for the functional and quantitative study of the muscular system and provide important information about the morphology and activity levels of the muscles.10 Information about alterations in muscles of the stomatognathic system, including bite force...

Stroke is a cerebrovascular disease that triggers changes in the central and peripheral nervous systems, and can compromise human body function. This cross-sectional observational study aimed to analyze the electromyographic (EMG) activity of the masseter and temporal muscles, orofacial soft tissue pressure, and strength of occlusal contacts in patients who had suffered a stroke. Twenty-four patients were divided into two groups: stroke (n = 12) and control (n = 12). The EMG of the masseter and temporal muscles was evaluated during mandibular rest, protrusion, right laterality, left laterality, and maximal voluntary contraction. The Iowa Oral Pressure Instrument (IOPI) was used to measure pressure from the tongue, lips, and buccinator muscles. A computerized system for occlusal analysis (T-Scan III) was used to measure the occlusal contact points of the right and left hemiarches (upper and lower) and the upper and lower first molars. Data were subjected to Student’s t-test (p < 0.05). The stroke group had lower normalized electromyographic activity, with a significant difference in the left temporal muscle during rest (p = 0.03) when compared to the control group. There was a significant difference between the groups in tongue pressure (p = 0.004) with a lower mean value in the stroke group. There was a significant difference between the groups in the evaluation of the occlusal contact points of the first permanent molars, with a lower mean percentage in the stroke group. The results indicate that stroke negatively affects functional performance of the stomatognathic system.

Desenho do estudo: estudo de caso. Introdução: A natação requer uma capacidade pulmonar efetiva para alcançar o melhor desempenho funcional e o método A Facilitação Neuromuscular Proprioceptiva (FNP) pode ser aplicado em um programa de treinamento cardiorrespiratório. Descrição do caso: Atleta 1, sexo masculino, 19 anos, 6 anos de treino borboleta, treina 6 vezes por semana durante 2 a 3 horas. Atleta 2, sexo masculino, 19 anos, 12 anos de prática de bruços, treina 6 vezes por semana durante 2 a 3 horas. Foram aplicados os seguintes exercícios: facilitação do músculo masseter e temporal, abaixamento do ângulo da boca, levantamento do músculo do ângulo da boca, platisma e diafragma, técnica de estabilização reversa no pescoço. Espessura e atividade miolométrica, pressão respiratória máxima, capacidade pulmonar e força de mordida foram avaliadas pré-intervenção com o método FNP. Resultados: Houve aumento do sinal eletromiográfico após aplicação de FNP nas condições usuais de mastigação com amendoim e passas, simetria na força máxima de mordida, aumento da espessura muscular, aumento da força e capacidade pulmonar em ambos os atletas após intervenção com FNP. Discussão: este caso teórico relata os resultados de dois atletas de natação que realizam intervenção com o método FNP, contribuindo para o aumento da espessura, atividade e força dos músculos mastigatórios e esternocleidomastóideos associados ao aumento da força e capacidade pulmonar, mostrando que a funcionalidade do o sistema estomatognático está intimamente relacionado com o sistema respiratório.

The above article, published online on 13 February 2015 in Wiley Online Library Early View (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal editors, Bernard Dan and Peter Rosenbaum, the MacKeith Press and John Wiley & Sons Ltd. The retraction has been made due to concerns relating to the validity of the EMG methodology and its interpretation, which affect the results of the paper. Reference