ABSTRACT
OBJECTIVE: To evaluate the phenotypic features of the masticatory biomechanics in atypical subjects with Down syndrome (DS). Its influence was analysed on sleep disorders, body adiposity and its risks, and some physicochemical properties of saliva. METHODS: Seventy subjects were enrolled to assess masticatory biomechanical function and divided into two groups: DS and control groups. Electrical activities of the masseter and temporal muscles (at rest and in maximum voluntary clench-MVC), maximum bite force-MBF and maximum mouth opening-MMO were investigated. Among the atypical subjects, just 24 participants underwent the anthropometry, the polysomnography II and the saliva testing (salivary flow rate-SFR, buffer capacity-BC and salivary cortisol levels, morning/SC-AM and night/SC-PM). RESULTS: MVC and MBF values showed high statistical significance in the control group (P < .001) than in the DS group of 35. MMO values were slightly increased in the DS group in relation to the control group. Overweight and obesity were found in both genders. Atypical women showed higher risk to develop cardiovascular-metabolic diseases than in atypical men. OSA severe was 20% for atypical women and 42.8% for atypical men, whereas snoring index was present in all genders. SFR was reduced in 100% of atypical subjects (hyposalivation in 10% women and 28.5% men). Furthermore, 100% BC, 66.6% SC-AM and 91.6% SC-PM showed normal patterns. CONCLUSION: Masseter and temporal muscle hypotonia was found in all atypical subjects with DS. This muscle dysfunction strongly was related to overweight/obesity, risks for development of cardiovascular/metabolic diseases, OSA severity, successive snoring episodes and salivary flow reduction in DS.
Subject(s)
Down Syndrome , Sleep Wake Disorders , Adiposity , Electromyography , Female , Humans , Male , Obesity , PolysomnographyABSTRACT
A síndrome de Down (SD) é uma das anomalias genéticas mais frequentes na população. Suas principais manifestações são deficiência intelectual, baixa estatura, hipotonia muscular, dismorfia craniofacial, cardiopatias congênitas, apneia obstrutiva do sono (AOS) e doença periodontal. O objetivo desse estudo foi avaliar os efeitos terapêuticos de um dispositivo mastigatório com hiperboloide (DMHB) sobre a função biomecânica mastigatória, registrando as atividades elétricas dos músculos temporal e masseter nas condições de repouso e em função (contração voluntária máxima CVM, Intercuspidação habitual máxima IHM). A amplitude de abertura de boca máxima (ABM) e intensidade de força de mordida máxima (FMM) foram também aferidas. Investigamos a sua influência nas propriedades físico-químicas da saliva, na qualidade do sono e nos indicadores de risco para doenças cardiometabólicas em pacientes com SD. Quatro pacientes, jovens e adultos, com SD do gênero masculino, participaram desse estudo. As análises clinico-laboratoriais foram realizadas antes e após a terapia com o DMHB. A função biomecânica foi analisada por meio de exame de eletromiografia de superfície dos músculos temporal (porção anterior) e masseter (porção superficial), em repouso e em função. Os exercícios oromotores, abertura de boca máxima (ABM) e força de mordida máxima (FMM) foram mensurados utilizando-se um paquímetro analógico e um transdutor de força de mordida, respectivamente. Os parâmetros salivares foram obtidos das amostras de saliva coletadas, com auxílio de uma bomba aspiradora, e analisadas em laboratório A qualidade do sono (distúrbios do sono, arquitetura do sono e condição do sistema cardiovascular) foram investigados por meio do exame de polissonografia tipo-II. O risco para doenças cardiovasculares e metabólicas foi evidenciado a partir do índice de massa corporal, circunferência do pescoço circunferência abdominal, e razão cintura quadril. Diante dos resultados, concluímos que a terapia com DMHB aumentou expressivamente a força de mordida de alguns pacientes com SD, a pesar de ter havido diminuição nas atividades elétricas dos músculos temporal e masseter em função. Essa terapia estimulou a produção de saliva. Com relação aos distúrbios do sono houve diminuição nos eventos de bruxismo do sono, mas influenciou no aumento da severidade da AOS e dos episódios de ronco. Na arquitetura do sono N2, N3 e REM evoluíram para a faixa de normalidade. Na condição do sistema cardiovascular, SaO2 média se manteve acima de 90%, contudo houve aumento do IDO. Quanto aos fatores de risco para o desenvolvimento de doenças cardiovasculares e metabólicas, alterações relevantes, não foram evidenciadas nesses indivíduos(AU)
Down syndrome (DS) is one of the most common genetic abnormalities in the populations. Its main manifestations are intelectual disability, short stature, muscle hypotonia, craniofacial dysmorphia, congenital heart disease, obstructive sleep apnea (OSA) and periodontal disease. The objective of this study was to avaluate the therapeutic effects of a hyperboloid masticatory function, recording the electrical activities of the temporal and masseter muscles at rest and in function (maximum voluntary contraction MVC, maximum habitual intercuspidation MHI). The amplitude of maximum mouth opening (MMO) and intensity of maximum bife force (MBF) were also measured. We investigated its influence on the physical and chemical properties of saliva, on the quality of sleep and on the risk indicators for cardiometabolic diseases in patients with DS. Four patients, young and adults, with male DS, participate in this study. Clinical and laboratory analyzes were performed before and after therapy with MDHB. The biomechanical function was analyzed by examining the surface electromyography of the temporal (anterior portion) and masseter (superficial portion) muscles, at rest and in function. Oromotor exercises, maximum mouth opening (MMO) and maximum bife force (MBF) were measured using an analog caliper and a bife force transducer, respectively. The salivary parameters were obtained from the collected saliva samples, with the aid of a vacum pump, and analyzed in the laboratory. Sleep quality (sleep disorders, sleep architecture and condition of the cardiovascular system) were investigated by means of the polysomnography type-II exam. The risk for cardiovascular and metabolic diseases was evidenced from the body mass index, neck circumference, abdominal circumference, and waist-to-hip ratio. In view of the results, we concluded that the therapy with MDHB significantly increased the bite strength of some patients with DS, despite the decrease in the electrical activities of the temporal and masseter muscles in function. This therapy stimulated the production of saliva. Regarding sleep disorders, there was a decrease in sleep bruxism events, but it influenced the increase in the severity of OSA and snoring episodes. In N2, N3 and REM sleep architecture evolved to the normal range. In the condition of the cardiovascular system, mean SaO2 remained above 90%, however there was an increase in the IDO. As for risk factors for the development of cardiovascular and metabolic diseases, relevant changes were not seen in these individuals(AU)
Subject(s)
Down Syndrome/diagnosis , Saliva/immunology , Sleep Wake Disorders/drug therapy , Muscle Hypotonia/complicationsABSTRACT
BACKGROUND: There are many comorbidities associated with Down syndrome (DS), including obstructive sleep apnea (OSA) and masticatory muscle alteration. Muscular hypotonia, in particular, of the masticatory and oropharyngeal muscles is one of the main characteristics of individuals with DS, resulting in impairments of speech, swallowing, and mastication in these individuals. In addition, total or partial obstruction of the airways during sleep can occur due to pharyngeal hypotonia, leading to snoring and to OSA. This progressive respiratory disorder is associated with a high risk of morbidity and mortality in individuals with DS. The aim of this research is to assess the therapeutic effects of surface neuromuscular electrical stimulation (NMES), the mastication apparatus (MA), and a mandibular advancement oral appliance (OAm) with an embedded thermosensitive microchip on the functions of masticatory muscles (bilateral masseter and temporal muscles), physiological sleep variables, and salivary parameters in adult patients with DS. METHODS: The patients with DS will be randomly selected and divided into three groups (DS-NMES, DS-MA, and DS-OAm) with a minimum of 10 patients in each group. A thermosensitive microchip will be embedded in the OAm to record its compliance. The therapeutic effects on masticatory muscle function will be investigated through electromyography, a caliper, and a force-transducer device; the sleep variables, in turn, will be evaluated by means of polysomnography. The physicochemical and microbiological properties of the saliva will also be analyzed, including the salivary flow, viscosity, buffer capacity, cortisol levels (susceptibility to psychological and/or physical stress), and Pseudomonas aeruginosa levels (risk of aspiration pneumonia) in these patients. The methods determined for this study will be carried out prior to and after 2 months of the recommended therapies. DISCUSSION: The primary outcomes would be the improvement and/or reestablishment of the function of masticatory muscles and the physiological sleep variables in this target public since individuals with DS commonly present generalized muscular hypotonia and dysfunction of the oropharyngeal musculature. As a secondary outcome indicator, the impact of the applied therapies (NMES, MA, and OAm) on the salivary microbiological and physicochemical properties in DS individuals will also be assessed. Furthermore, the compliance of OAm usage will be measured through a thermosensitive microchip. TRIAL REGISTRATION: Registro Brasileiro de Ensaios Clínicos, RBR-3qp5np . Registered on 20 February 2018.
