Analise eletromiografica do musculo orbicular do olho em pacientes portadores de protese ocular antes e apos a instalação proteica

Orientador : Mathias VittiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Além da função primária de proteção das cavidades da face, os músculos cutâneos são de suma importância na estética e na expressão facial para o homem. São músculos que se apresentam localizados superficialmente na face e seus estudos eletromiográficos têm contribuído para sua melhor descrição. O objetivo do presente trabalho é o de analisar comparativamente por meio de exame eletromiográfico o músculo orbicular do olho de pacientes controles e pacientes com indicação para receber prótese ocular (pacientes tratados). Para este trabalho foram estudados o músculo orbicular do olho de 24 pacientes do sexo masculino, com a idade média de 32,5 anos, que foram divididos em dois grupos: o primeiro grupo formado por 12 pacientes portadores de problemas oculares do lado esquerdo (ausência do globo ocular esquerdo), com indicação para receber prótese ocular, o segundo grupo formado por: 12 pacientes controles. Todos os pacientes indicados para receber prótese ocular tiveram perda do globo ocular causada por diferentes tipos de acidentes como: explosivos, projéteis, bola, farpas de madeira e acidente de trânsito, exceto um, que teve toxoplasmose, mas foram todos considerados normais na anamnese física e psicológica. Os exames foram realizados com o Eletromiógrafo K6-I EMG Light Channel Surface Electromyography (Myo-tronics CO. Seattle, WA, EUA) de oito canais. Diante dos resultados encontrados, nas condições do presente trabalho, é lícito concluir que: 1. O uso da prótese ocular melhora as condições estéticas do paciente mutilado de face. 2. A perda do globo ocular, leva a um aumento da atividade eletromiográfica do músculo orbicular do olho. 3. O uso da prótese ocular, por um período de tempo de 7 dias ( uma semana), não foi suficiente para diminuir esta atividade muscular, mesmo constatando-se clinicamente, perfeita adaptação da prótese. 4. O uso da prótese ocular não interferiu na condição clínica de Abertura e Fechamento Forçado da Pálpebra (A/FF)Abstract: Besides the primary function of protecting the facial cavities, the cutaneous muscles are of paramount importance concerning esthetics and facial expression of the human being. They are muscles superficially localized in the face and the electromyographic studies have contributed a lot for their better description. The aim of this study was to comparatively analyze through electromyographic examination the orbicular muscle of normal subjects and of patients indicated to receive ocular prosthesis. In this investigation the orbicular muscles of 24 male subjects were studied. Their mean age was 32.5 years and they were allocated into two groups as follows: The first group was made up by: 12 patients with ocular problems in the left side (absence of the left eyeball) indicating an ocular prosthesis. The second group was formed by: 12 normal subjects. All the patients indicated for ocular prosthesis had lost their eyeballs due to different kinds of accidents as: explosives, projectiles, balls, wooden splinters and traffic accidents, the exception being one who had toxoplasmosis. Notwithstanding, all of them were considered normal in the physical and psychological anamnesis. The determinations were carried out using the eight channel Electromyograph K6-I - Light Channel Surface Electromyography (Myotronic CO. Seattle, W A, USA). Considering the results found under the conditions of this study, we may conclude that: 1. The use of the ocular prosthesis improves the esthetic condition of patients mutilated in the face. 2. The loss of the eyeball increases the orbicular muscle electromyographic activity. 3. The use of the ocular prosthesis during 7 days (one week) has not been sufficient to diminish this muscular activity, even when a perfect adaptation of the prosthesis has been clinically observed. 4. The use of the ocular prosthesis did not interfere with the Forced Opening and Closure of the Eyelids (AJFF) clinical conditionMestradoMestre em Biologia e Patologia Buco-Denta

Severity of Sleep Bruxism and its Implications for the Stomatognathic System in Healthy Subjects

BACKGROUND: Sleep bruxism (SB) changes the functionality patterns of the stomatognathic system. However, its severity can be an aggravating factor in the function of this complex system. AIM: The purpose of the study was to investigate the stomatognathic system of healthy subjects with different severity of SB, as determined by BiteStrip. METHODS: Thirty-four subjects were divided into two groups: Mild SB (n = 15) and severe SB (n = 19). Electromyograph was used to evaluate the electromyographic activity of the right masseter (RM), left masseter (LM), right temporal (RT), and left temporal (LT) muscles at mandibular rest, right and left laterality, protrusion, and maximum voluntary contraction. Molar bite force was measured by the dynamometer. The data were tabulated and submitted for statistical analysis (p < 0.05). RESULTS: Molar bite force was significantly lower in the severe SB group. There was a significant increase in electromyographic activity in the severe SB group for the mandibular rest tasks (RM, RT, and LT), protrusion (RM, LM, RT, and LT), and right and left laterality in the temporalis muscles. There was a significant decrease in electromyographic activity in the severe SB group in maximum voluntary contraction for the masseter and temporalis muscles. CONCLUSION: Subjects with severe SB demonstrated greater functional impairment of the stomatognathic system, mainly affecting the electromyographic activity and molar bite force

Electromyographic analysis of the masseter and temporalis muscles and bite force in a patient treated by functional maxillary orthopedics: a case report

This case report evaluated electromyographic activity of the masseter and temporalis muscles and molar bite force, before and after with functional orthopedic. A 65 years woman presenting with orofacial pain symptoms, cervical tension, condyle subluxation and osteoarthrosis. The patient was diagnosed with temporomandibular dysfunction and treated with use of a Simões Network 9 modified type functional maxillary orthopedics appliance. The Myosystem BR1 apparatus was used to analyze the electromyographic activity of the masseter and temporalis muscles. The maximum molar bite force was measured with the digital dynamometer (Kratus). This study showed increased EMG activity of the masseter and temporalis muscles in postural conditions of mandible and molar bite force after 12 months of treatment. After twelve months of treatment, the patient had lack of pain symptoms as well as an improvement in the balance of the mastication muscles, as demonstrated by EMG activity and maximum molar bite force

Electromyographic evaluation in children having rapid maxillary expansion

Introduction: The aim of this study was to analyze the electromyographic activity of the masseter and temporalis muscles of children having rapid maxillary expansion (RME) with a bonded rapid maxillary expansion appliance. Methods: The sample consisted of 27 children (mean age, 8.6 years) with posterior crossbite who required RME treatment. Electromyographic activity of the masseter and temporalis muscles was analyzed before treatment and after the appliance was removed. The mean interval between the 2 analyses was 5 months. Muscular activity was electromyographically analyzed in rest position, and with maximum voluntary dental clenching and chewing. Differences in the 2 measurements were evaluated by using paired t tests. Results and Conclusions: Electromyographic analysis showed that activity of the masseter and temporalis muscles increased significantly after the expansion appliance was removed during rest, dental clenching, and habitual chewing. (Am J Orthod Dentofacial Orthop 2009;136:355-60

Stomathognatic system function in indigenous people from Brazilian Xingu villages: An electromyographic analysis.

The maintenance of postural balance can be influenced by the lifestyle of a population. This study aimed to determine the electromyographic activity of the masseter and temporalis muscles during mandibular tasks and habitual and non-habitual chewing in indigenous individuals to reveal the differences among white Brazilian individuals. Sixty Brazilians (18 and 28 years) were divided into two groups: 30 Xingu indigenous individuals and 30 white Brazilian individuals, with 20 men and 10 women in each group. The individuals were assessed using the normalized electromyographic activity of mandibular tasks (rest, protrusion, right and left laterality) and electromyographic activity of masticatory cycles in habitual (peanuts and raisins) and non-habitual (Parafilm M) chewing. Data were analyzed using Student's t-test (p < .05). Comparisons between the groups demonstrated significant differences. Indigenous individuals group presented a decrease in the normalized electromyographic activity of the masticatory muscles during mandibular rest [right masseter (p = .002) and left masseter (p = .004) muscles]. There was increase in the normalized electromyographic activity during protrusion [left temporal (p = .03) muscle]. There was increase in the electromyographic activity during chewing: peanuts [right masseter (p = .001), left masseter (p = .001) and right temporal (p = .01) muscles], raisins [right masseter (p = .001), left masseter (p = .002), right temporal (p = .008), left temporal (p = .01) muscles] and Parafilm M [left masseter muscle (p = .05)]. From the findings of this study, we concluded that in the comparison between indigenous and white individuals, positive changes were observed in the electromyographic pattern of the masticatory muscles in the mandibular postural conditions, with greater masticatory efficiency in the indigenous group

Alterations in the stomatognathic system due to amyotrophic lateral sclerosis

Abstract Objectives: To compare the molar bite force, electromyographic activity, chewing efficiency and thickness of the masseter and temporalis muscles in individuals with amyotrophic lateral sclerosis (ALS) and healthy individuals. Material and Methods: Thirty individuals enrolled in the study were divided into the study group (with ALS, n=15) and control group (healthy individuals, n=15). Data regarding molar bite force (right and left), electromyographic activity (mandibular rest, right and left laterality, protrusion, and maximum voluntary contraction), chewing efficiency (habitual and non-habitual), and masticatory muscle thickness (rest and maximum voluntary contraction) were tabulated and subjected to statistical analysis (Student’s t-test, p≤0.05). Results: Comparisons between the groups demonstrated a statistically significant increase in the electromyographic activity of the right masseter (p=0.03) and left masseter (p=0.03) muscles during mandibular rest; left masseter (p=0.00), right temporalis (p=0.00), and left temporalis (p=0.03) muscles during protrusion; and right masseter (p=0.00), left masseter (p=0.00), and left temporalis (p=0.00) muscles during left laterality, in individuals with ALS as compared with healthy individuals. A statistically significant decrease was observed in the habitual chewing efficiency of the right masseter (p=0.00) and right temporalis (p=0.04) muscles in individuals with ALS. No statistically significant difference between the groups was found the masticatory muscle thickness and maximal molar bite force. Conclusions: ALS may lead to modifications in the activities of the stomatognathic system, including muscular hyperactivity and reduction in chewing efficiency; however, no change has been observed in the masticatory muscle thickness and molar bite force

Evaluation of molar and incisor bite force in indigenous compared with white population in Brazil

The purpose of this study was to deter-mine maximum bite force in molar and incisor regions in young Brazilian indigenous individuals, who have had a natural diet since birth, and compare the sample with white Brazilian individuals. To do this, individuals were paired one-to-one (same weight, height, and Class I facial pattern). A secondary purpose was to elucidate the relation between bite force and gender in both populations. Eighty-two Brazilians took part in this study. Participants were aged between 18 and 28 years and were divided into two groups: 41 Xingu indigenous individuals and 41 white Brazilian individuals, with 28 men and 13 women in each group. The inclusion criteria were: having complete dentition; normal occlusion; no neurological, psychiatric or movement disorders.; no reports of toothaches; having satisfactory periodontal health; absence of large facial skeletal alterations (typical Class II and Class III individuals); and no previous treatments using occlusal splints. To measure maximum bite force, a digital dynamometer model IDDK (Kratos-Equipamentos Industriais Ltda, Cotia, Sao Paulo, Brazil) was used, with a capacity of 1000 N, adapted for oral conditions. Assessments were made in the first molar (right and left) and central incisive regions. Results reveal that mean maximum bite forces in indigenous individuals of the right molar is 421 N, left molar 429 N and incisor region is 194 14 and for white individuals of the right molar is 410 N, left molar 422 N and incisor region is 117 N. Comparing indigenous with white individuals, maximal bite force showed a tendency of being greater in the indigenous group. It was observed that the incisor region showed statistical significance (p < 0.0005) but no significance was observed in the molar region. Moreover, indigenous men showed the highest bite force values. (C) 2007 Elsevier Ltd. All rights reserved

Effect of denture quality on perioral muscle activity during speech

This study aimed to evaluate the electromyographic activity of the orbicularis oris muscle in patients using clinically inadequate conventional dentures before and after the insertion of clinically acceptable new convencional denture. Six patients, using inadequate dentures, were asked to pronounce the syllables PAH, BAH, MAH, SAH, FAH, VAH, MEE and the word MISSISSIPI. During this activity, we analyzed the Electromyographic activity of the orbicularis oris muscle. This was done before and after changing the inadequate denture for a acceptable new denture. A K6-I EMG Light Channel Surface Electromyograph was used (Myo-tronics Co). Results were analyzed by repeated measures ANOVA, with 3 sources of variation (Syllables, Muscles, and Clinical Conditions). ANOVA revealed higher electromyographic readings in the mandibular fascicle of the orbicular oris muscle, as compared to those of the maxillary fascicle (F = 79.02; P<0.01). The comparison regarding clinical conditions indicated higher electromyographic values after insertion of acceptable new denture (F= 32.64; P<0.01). Clinical condition after the implantation of a new well-adapted complete denture revealed higher electromyographic activity levels than those measured with the use of maladapted complete dentures