▼ 

学位の種類: 博士（歯学）. 報告番号: 甲第4144号. 学位記番号: 新大院博（歯）甲第342号. 学位授与年月日: 平成28年3月23日

We aimed to quantify masseter muscle stiffness in patients with masticatory myofascial pain. Masseter muscle stiffness was measured by acoustic radiation force impulse (ARFI) imaging, which expresses stiffness as shear wave velocity (Vs). Muscle stiffness was 1.96 m/s (4.28 kPa) in 11 patients in Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) group Ia, 2.03 m/s (4.53 kPa) in 11 patients in RDC/TMD group Ib and 1.37 m/s (2.10 kPa) in 13 control subjects. Vs was significantly greater in groups Ia and Ib than in control (Steel–Dwass test, p <0.05). Characteristic pain intensity (CPI) became clear as an independent factor impacting Vs (partial regression coefficient = 0.625; multiple regression analysis, p < 0.05). Masseter muscles stiffness correlated with CPI (Spearman’s rank order test, p < 0.05) and was about two-fold greater in groups Ia and Ib than in healthy subjects.

▼ 

Introdução: A disfunção temporomandibular é uma designação que abrange vários problemas clínicos envolvendo a musculatura mastigatória, a ATM e as estruturas associadas a ambos. Este trabalho pretende realizar uma abordagem histórica, definindo e clarificando definições, terminologias e índices mais utilizados, em investigação na Oclusão. Por fim, realizar uma revisão bibliográfica apoiada num grupo de casos sobre a investigação em si, ou seja, limitações dos estudos e dificuldades da investigação em Oclusão. Metodologia: Realizámos um estudo observacional longitudinal em que avaliámos uma amostra de 87 pacientes consultados na Clínica Universitária da UCP-Viseu e na Clínica Médica Corpus Dental, com idade entre os 20 e 70 anos. Cerca de 43,7% dos indivíduos pertenciam ao género masculino e 56,3% ao feminino. Estes foram sujeitos ao inquérito Índice RDC/TMD (“Research Diagnostic Criteria for Temporomandibular disorders”) eixo I. No final analisámos as dificuldades e limitações do estudo, produzindo uma lista que pode auxiliar futuros estudos. Resultados: A dor orofacial foi referida por 43,7% da amostra, sendo 32,2% indivíduos do género feminino. Dos pacientes com dor orofacial 73,7% apresentava dor á palpação muscular, e 42,1% foi diagnosticada com mialgia dos músculos da mastigação. Destes 81,3% foram sujeitos a tratamento com placas de relaxamento muscular, dos quais 68,8% afirmaram no final deste estudo, estar satisfeitos com o tratamento. Conclusões: De modo a minimizar a controvérsia dos estudos sobre DTM, dificuldades e limitações, é importante que este obedeça a um conjunto de características como existência de um grupo controle e homogeneidade da amostra, que deve ser grande e significativa. Apesar de serem necessários mais estudos com uma amostra maior, concluímos que uma parte significativa da população sofre de sintomas dolorosos na face, e que as placas de relaxamento muscular contribuem para a remissão do sintoma.

Introduction: The temporomandibular joint dysfunction is a term that encompasses many clínical problems involving the masticatory muscles, the TMJ and associated structures. This work intends to conduct a historical approach, defining and clarifying definitions, terminologies and indexes used in occlusion’s research. Finally, conduct a literature review supported by a group of cases about the investigation itself, limitations of the studies and specific difficulties of research in Occlusion. Methods: We conducted a longitudinal study in which we evaluated a sample of 87 patients consulted in the University Clinic of UCP-Viseu and in the Medical Clinic Corpus Dental, aged between 20 and 70 years. Approximately 43,7% of the individuals were males and 56,3% were females. These were both under investigation Index RDC/TMC (“Research Diagnostic Criteria for Temporomandibular Disorders”) Axis I. In the end of the study, we analyze the difficulties and limitations, producing a checklist to future studies. Results: The orofacial pain was reported by 43,7% of the sample, which 32,2% of individuals…

Advisors/Committee Members: Leitão, Jorge, Ribeiro, Octávio.

▼ The overall goal of this thesis was to broaden knowledge of pain mechanisms in myofascial temporomandibular disorders (M-TMD). The specific aims were to: • Develop a quality assessment tool for experimental bruxism studies (study I). • Investigate proprioceptive allodynia after experimental tooth clenching exercises (study II). • Evaluate the release of serotonin (5-HT), glutamate, pyruvate, and lactate in healthy subjects (study III) and in patients with M-TMD (study IV), after experimental tooth clenching exercises. In (I), tool development comprised 5 steps: (i) preliminary decisions, (ii) item generation, (iii) face-validity assessment, (iv) reliability and discriminative validity testing, and (v) instrument refinement. After preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was generated. Eleven experts were invited to participate on the Delphi panel, of which 10 agreed. After four Delphi rounds, 8 items remained and were included in the Quality Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS). Inter-observer reliability was acceptable (k = 0.77), and discriminative validity high (phi coefficient 0.79; P < 0.01). During refinement, 1 item was removed; the final tool comprised 7 items. In (II), 16 healthy females participated in three 60-min sessions, each with 24- and 48-h follow-ups. Participants were randomly assigned to a repetitive experimental tooth clenching task with 10 a clenching level of 10%, 20%, or 40% of maximal voluntary clenching force (MVCF). Pain intensity, fatigue, perceived intensity of vibration (PIV), perceived discomfort (PD), and pressure pain threshold (PPT) were measured throughout. A significant increase in pain intensity and fatigue but not in PD was observed over time. A significant increase in PIV was only observed at 40 min, and PPT decreased significantly over time at 50 and 60 min compared to baseline. In (III), 30 healthy subjects (16 females, and 14 males) participated in two sessions at a minimum interval of 1 wk. Microdialysis was done to collect 5-HT, glutamate, pyruvate, and lactate and to measure masseter muscle blood flow. Two hours after the start of microdialysis, participants were randomized to a 20- min repetitive experimental tooth clenching task (50% of MVCF) or a control session (no clenching). Pain intensity was measured throughout the experiment. Substance levels and blood flow were unaltered at all time points between sessions, and between genders in each session. Pain intensity was significantly higher after clenching in the clenching session compared to the same time point in the control session. In (IV), 15 patients with M-TMD and 15 healthy controls participated in one session and the methodology described above was used. M-TMD patients had significantly higher levels of 5-HT and significantly lower blood flows than healthy controls. No significant differences for any substance at any time point were observed between groups. Time and group…

▼ 

O objetivo deste trabalho foi analisar a influência da ansiedade e do estresse no limiar de dor à pressão (LDP) de músculos mastigatórios, numa amostra de estudantes universitários em diferentes períodos do ano letivo. Para este propósito, foram selecionados 45 indivíduos, sendo 29 estudantes, que apresentavam DTM de origem miogênica seguindo critérios de inclusão propostos pelo Research Diagnostic Criteria (RDC) e 16 que não apresentavam características de DTM, do gênero feminino, equilibrados em relação à idade. Utilizando um algômetro (KRATOS®) foram realizadas tomadas bilaterais dos limiares de dor à pressão (LDP) dos indivíduos da amostra nos músculos masseter, temporal anterior, médio e posterior. Além disso, os participantes foram solicitados a responder questionários multidimensionais, através do Inventário de Ansiedade de Beck (BAI) e o Inventário de Sintomas de Stress de Lipp (ISSL), para mensurar reações emocionais ou afetivas em situações que causem estresse e/ou ansiedade. Também, o nível de dor foi registrado pela Escala de Análise Visual (EAV). Todos os exames foram realizados em quatro momentos distintos (T1, T2, T3 e T4) tendo como parâmetro o período de avaliações acadêmicas da Faculdade de Odontologia de Bauru. Os dados obtidos foram submetidos à análise estatística (ANOVA, Teste de Tukey, Teste de Friedman e Mann-Whitney), em um nível de significância de 5%. A comparação entre os diferentes tempos do estudo nos 2 grupos mostrou diferença estatisticamente significativa (p<0,05), sendo que o período das avaliações mostrou maiores níveis de estresse e ansiedade e menores valores de LDP. Sob o ponto de vista do músculo nos diferentes grupos e nos diferentes tempos, foram encontradas diferenças estatisticamente significativas (p<0,05). Os resultados da Escala de Análise Visual mostraram diferenças estatisticamente significantes entre o grupo sintomático e o grupo assintomático em T1, T2, T3 e T4. Com relação ao estresse e ansiedade, não houve diferenças estatisticamente significante entre os grupos. Houve, no entanto, uma associação entre o aumento do estresse e da ansiedade e diminuição dos valores de LDP em cada tempo. Concluiu-se que existe relação entre estresse e ansiedade e LDP tanto para indivíduos assintomáticos quanto para sintomáticos com DTM de origem miogênica.

The aim of this research was to evaluate the influence of stress and anxiety on the Pressure Pain Threshold (PPT) of the masticatory muscles and on the subjective pain report of dental students of the Bauru School of Dentistry (University of São Paulo, Brazil) at different situations. Forty-five females, matched for age, were divided into two groups: 29 presenting with myofascial pain, according to the RDC/TMD criteria, and 16 with no TMD signs or symptoms. PPT measurements were taken bilaterally at the masseter, anterior, middle and posterior temporalis muscles in four different occasions throughout the academic year. The Achilles tendon was used as control. In order to quantify emotional or affective reactions under…

Advisors/Committee Members: Conti, Paulo Cesar Rodrigues.

▼ 

The significance of masticatory muscle function with regard to normal function and functional disorders of the craniomandibular system has been proven by numerous studies. The assessment of the electrical muscle activity by means of electromyography and the measurement of the thickness of the muscles by means of ultrasound imaging are diagnostic methods for the estimation of the masticatory muscle function. Among the jaw closing muscles, the masseter makes an essential contribution both to the closing force of the mandible and when overloaded to facial pain. Due to its bulky morphology and superficial position is easily accessible for quantative analysis. Masseter muscle thickness and its electromyographic activity have been shown to correlate significantly with bite force. Consequently, it could be inferred that masseter muscle thickness would correlate with its electromyographic activity. The few studies available so far in the literature, examining the relation of masseter muscle thickness to its electromyographic activity, have not shown a clear correlation. The aim of the present study was to assess the thickness of the masseter muscle by means of ultrasounds, to record the electrical muscle activity by means of electromyography and to estimate the correlation of masseter muscle thickness to its electromyographic activity. Additionaly, the reproducibility of the two methods was assessed and differences between the right and left masseter muscle were evaluated. The study comprised 110 young women for initial examination who served to form a study group of 52 subjects (mean age 23,7±2,5 years) without craniomandibular disorders and with full continuous dental arches. All the participants were students at the Aristotle University of Thessaloniki. They were informed about the aims of the study and the study procedure and informed consent was received. Electrical activity was recorded bilaterally with bipolar surface electrodes and the raw signal was analyzed by means of an electromyographic system (Myotronics-Noromed, Inc). The thickness of the masseter muscle was measured bilaterally with a real-time scanner (Pie Medical Scanner 480, 7,5 MHz). The error of the method in the electromyographic and ultrasound techniques was calculated by double recordings in 15 randomly selected subjects in four weeks interval. All the recordings and measurements were performed by the writer of the present study. The measurement error was found to be small, not exceeding 18,01 μV (5,02%) for the recording of the electromyographic activity and 0,19 mm (1,41%) for the measurement of masseter muscle thickness.

Ο ρόλος των μασητήριων μυών είναι καθοριστικός για την ομαλή λειτουργία του στοματογναθικού συστήματος (ΣΓΣ) και η εκτίμηση της λειτουργικής τους κατάστασης είναι χρήσιμη αρκετές φορές για διαγνωστικούς σκοπούς. Για το σκοπό αυτό έχουν χρησιμοποιηθεί τόσο η καταγραφή της ηλεκτρομυογραφικής τους δραστηριότητας όσο και η μέτρηση του πάχους τους με τη χρήση υπερηχογράφου. Ο μασητήρας μυς είναι από τους πιο δυνατούς μασητήριους και…

▼ 

O objetivo deste trabalho foi analisar a influência do ciclo menstrual nas alterações de limiar de dor à pressão (LDP) na musculatura mastigatória de mulheres com sinais e sintomas de Disfunção Temporomandibular (DTM). Inicialmente 47 voluntárias entre 18 e 40 anos participaram do estudo, das quais 36 foram incluídas no experimento: 15 com sinais e sintomas de DTM (7 sob terapia com contraceptivos orais (CO) e 8 sem CO) e 21 saudáveis, sem sinais e/ou sintomas de DTM (8 com CO e 13 sem CO). Os LDPs dos músculos masseter e temporais (anterior, médio e posterior), e do tendão de Aquiles foram medidos bilateralmente, por meio de um algômetro, durante 2 ciclos menstruais consecutivos, nas 4 diferentes fases: menstrual (dias 1-3), folicular (dias 5-9), periovulatória (dias 12-16) e lútea (dias 19-23). Em cada fase do ciclo, as voluntárias relataram sua dor em uma Escala de Análise Visual (EVA). Os resultados foram submetidos à análise de variância a 3 critérios para mensurações repetidas, a um nível de significância de 5%.Foram encontrados LDPs significativamente menores nos músculos temporal e masseter e no tendão de Aquiles das mulheres com DTM quando comparado às mulheres assintomáticas, independentemente da fase do ciclo e do uso de contraceptivos (p < 0,05). De uma maneira geral, os LDPs foram maiores em mulheres em terapia com contraceptivos orais, quando comparado às mulheres sem terapia. Parece não existir influência das diferentes fases do ciclo menstrual no LDP, independentemente da presença ou não de DTM.

The aim of this study was to investigate the influence of the menstrual cycle on the Pain Pressure Threshold (PPT) figures of the masticatory muscles in women with signs and symptoms of Temporomandibular Disorders (TMD). Forty-seven volunteers (ages between 18-40 years-old) were initially recruited for this purpose. According to the criteria adopted, 36 were included. The experimental group was composed of 15 women with myofascial pain (RDC/TMD) (7 under oral contraceptive medication), while 21 women with no TMD signs or symptoms (8 under oral contraceptive medication) composed the control group. The PPT values of masseter and temporalis (anterior, middle, and posterior regions) muscles, as well as the Achilles? tendon were bilaterally screened during two consecutive menstrual cycles, in the following phases: menstrual (day 1-3), follicular (day 5-9), periovulatory (day 12-16) and luteal (day 19-23). A visual analog scale (VAS) was used to address subjective pain in each menstrual phase. Data were submitted to 3-way ANOVA for repeated measurements, with a 5% significant level. The PPT values were significantly lower in the temporalis, masseter, and the Achilles? tendon of TMD patients when compared with the asymptomatic controls, regardless of the menstrual cycle phase or the use of oral contraceptives (p<.05). Overall, the PPT values were higher for patients under oral contraceptive therapy, while VAS was, in general higher at the menstrual phase (p<.05). It appears that the different phases of menstrual…

Advisors/Committee Members: Conti, Paulo Cesar Rodrigues.