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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Odos ir minkštųjų audinių standumo charakteristikų skaičiavimas baigtinių elementų metodu / Rigidity Characteristic`s Calculation of Skin And Soft Tissue By Finite Element Method

Motiečiūtė, Lina 19 June 2006 (has links)
Stiffnes of leg's receiver and skin and soft tissues at contact place are researched in the master thesis. Using the finite elements method with digital ANSYS programmable packet was made non-linear model of leg's prothesis receiver and stump of soft tissues . Made calculiation have shown that deformation ratio in stump and receiver contact declines when the lood increases. Therefore it is very important to evaluate not only the height of desabled persion but also his weight durind estimation the magnitude of deviations of leg prosthesis manufacturing and assembly.
182

Conception et évaluation d’un modèle biomécanique, éléments finis, patient-spécifique, du pied humain. Applications en podologie, orthopédie et diabétologie : applications en podologie, orthopédie et diabétologie / Design and evaluation of a biomechanical, finite elements and patient-specific model of the human. : foot.Applications in podiatry, orthopedics and diabetology

Perrier, Antoine 04 July 2016 (has links)
Conception et évaluation d’un modèle biomécanique, éléments finis, patient-spécifique, du pied humainApplications en podologie, orthopédie et diabétologieLe pied est une des structures les plus complexes du corps humain. Avec 28 os, 33 articulations et une centaine de structures ligamentaires, cette entité poly articulée est le résultat d’une hyperspécialisation ayant contribué à faire de l’homme l’unique primate totalement bipède. Quelque soit le relief, quelque soit le mouvement en cours, le pied transmet au tibia le bon vecteur force afin de finaliser le geste de la manière la plus précise et économe en énergie possible dans l’objectif de préparer l’action des segments sus jacents. Ainsi, en cas de lésion d’une des structures, l’ensemble du complexe pied doit pouvoir s’adapter, si ce n’est pas le cas, les tissus mous, les articulations ou les os seront fragilisés et verront leur fonction propre au sein de ce complexe altérée.Prédire l’adaptation du pied à une modification structurelle, tissulaire, neurologique ou fonctionnelle est un enjeu important dans l’estimation du risque lésionnel.Afin d’initier une réponse à ces problématiques, nous avons décidé au cours de cette thèse de modéliser le pied humain avec des outils mathématiques de simulation biomécanique. Dans un premier temps, un modèle tridimensionnel musculo-squelettique du pied a été reconstruit à partir d’imagerie scanner. Le pied polyarticulé en multicorps rigides obtenu possède des articulations uniquement contraintes par les ligaments et contacts osseux. Les muscles ont été implémentés afin de piloter le modèle en dynamique directe. Enfin, les tissus mous comme les volumes musculaires, le gras et la peau ont été maillés en éléments finis. L’utilisation d’un environnement de programmation multi-physique open source (Artisynth) a permis de coupler la modélisation musculo-squelettique et éléments finis.• L’adaptation du pied au sol en orthostatisme a été évaluée par comparaison des cartographies de pression d’une mise en charge simulée avec la mise en charge réelle du sujet.• Le contrôle moteur du pied en chaine ouverte par l’activation des muscles extrinsèques a été évalué en comparant la cinématique du modèle biomécanique pilotée par électromyographie avec la cinématique capturée en laboratoire sur un mouvement d’abduction – adduction.• Nous avons ensuite cherché à comprendre comment une arthrodèse de cheville modifie la cinématique du pied à la contraction musculaire, l’objectif étant d’aider au réglage chirurgical du geste.• Enfin nous avons utilisé les dernières avancées sur la physiologie de la plaie de pression afin de prédire le risque d’ulcération sur un pied neuroarthropatique diabétique par simulation numérique.Le modèle ainsi que les routines de simulations mis en place nous permettent d’avoir un des modèles les plus aboutis du pied humain utilisant aussi bien des données physiques externes comme les données baropodométriques, les données d’analyse quantifiée du mouvement ou encore les données électromyographiques. Ce modèle permettra par l’intermédiaire d’outils de mesh-matching d’obtenir des modèles patients spécifiques. Les domaines d’applications porteront sur l’aide au geste chirurgical, la prévention des risques d’ulcération, l’analyse avancée des relations entre le pied et le membre inférieur, mais aussi l’aide à la conception de prothèse en orthopédie classique et en mécatronique. / Biomechanical modeling of the human foot. Application to the healthy and pathological subject.The foot is one of the more complex structures of the human body. With 28 bones, 33 joints and a hundred ligamentous structures, this articulated entity is the result of a hyper specialization that makes humans the only obligate bipedal primates. Whatever the terrain, whatever the current movement, the foot transmits to the tibia the right force vector to finalize the gesture in the most precise and efficient manner and prepares the action of the lower limb. Thus, in case of injury to one of the structures, the whole foot complex must adapt if it is not the case, soft tissues, joints or bones are fragile and will have their own function within this complex altered .Predicting the foot’s adaptation of a structural, tissue, neurological or functional modification is an important issue in estimating the risk lesion on locomotion, in the design of therapeutic footwear and orthotics of the degenerative foot, but also in the future of this complex in situations where the boundary conditions change like working in microgravity or foot exoskeleton coupling.To initiate a response to these problems, we decided during this thesis to model the human foot with mathematical tools for biomechanical simulation. Initially, a musculoskeletal three-dimensional model of the foot was reconstructed from computed tomography. The multi-articulated foot joints constraints obtained by ligaments and bone contact. The muscles have been implemented to control the model in direct dynamic. Finally, the soft tissues such as muscle volume, fat and skin were meshed into finite elements. Using a multi-physics open source programming environment (Artisynth) allowed to couple musculoskeletal modeling and finite elements.• Adapting the foot on the ground in upright posture was evaluated by comparing the pressure maps at a simulated load setting with the actual loading pressure map of the subject.• The motor control of foot in opened chain by activation of the extrinsic muscles was assessed by comparing the kinematics of the biomechanical model piloted by electromyography with kinematics captured in the laboratory on a movement of abduction - adduction.• We then sought to understand how an ankle arthrodesis alter the kinematics of the foot muscle contraction, with the aim of helping the surgical setting gesture.• Finally, we used the latest advances in the physiology of a pressure ulcer to predict the risk of ulceration on diabetic foot with Charcot neuro arthropathy by numerical simulation.The model and simulation routines in place allow us to have one of the most successful models of the human foot using both external physical data like pedobarographic data, motion analysis data or electromyography data. This model will allow through mesh-matching tool to obtain specific patient models. The fields of applications will focus on assisted surgery, prevention of ulceration, advanced analysis of relations between the foot and the leg, but also will help the prosthesis design in orthopedic and mechatronics.
183

Malocclusions in relation to facial soft tissue characteristics, facial aesthetics and temporomandibular disorders in the Northern Finland Birth Cohort 1966

Krooks, L. (Laura) 23 October 2018 (has links)
Abstract Epidemiological studies on malocclusions in Finland have so far concentrated on children and adolescents. Regarding the Finnish adult population, there is scarce epidemiological knowledge available on malocclusions even though the number of adults seeking orthodontic treatment has increased during the last decades. Occlusion is an important factor in the function of the masticatory system, and its role in the aetiology of temporomandibular disorders (TMD) is one of the most disputed topics in dentistry. Malocclusions can affect the characteristics of the facial soft tissue profile. The aim of the study was to investigate the prevalence of malocclusions and the role of occlusion in TMD as well as the association of facial characteristics with malocclusions and facial aesthetics. The study population consisted of subjects from the Northern Finland Birth Cohort 1966 (NFBC1966). Data were collected using questionnaires, standardized clinical examination and facial photos. The profile photographs were analysed using linear and angular soft tissue cephalometric measurements. The most common malocclusion in the NFBC1966 subjects was lateral crossbite. This study showed a significant association between asymmetric malocclusions and TMD. TMD signs associated significantly with lateral crossbite, scissors bite, negative overjet, and the length and lateral deviation in slide between retruded contact position and intercuspal position (RCP-ICP). Soft tissue profile characteristics were highly correlated with negative overjet. The ANB-angle was significantly associated with the perception of facial attractiveness. In conclusion, malocclusions were associated with signs and symptoms of TMD in the Finnish adult population. Overjet appeared to affect the facial profile more than overbite. Facial convexity seemed to be a more important determinant of facial aesthetics for orthodontists than for dentists and laypersons. / Tiivistelmä Suomalaiset epidemiologiset tutkimukset purennan poikkeamista ovat tähän asti keskittyneet tarkastelemaan lapsia ja nuoria. Tarkkaa epidemiologista tietoa suomalaisen aikuisväestön purennan poikkeamista on tällä hetkellä saatavilla vain niukasti, vaikka oikomishoitoon hakeutuvien aikuispotilaiden määrä on Suomessa viime vuosina lisääntynyt. Purennalla on tärkeä merkitys purentaelimistön toiminnassa ja sen rooli purentaelimistön toimintahäiriöiden (TMD) etiologiassa on yksi kiistanalaisimpia aiheita hammaslääketieteessä. Purennan poikkeamat voivat vaikuttaa myös kasvojen pehmytkudosprofiilin piirteisiin. Tutkimuksen tarkoituksena oli selvittää purennan poikkeamien esiintyvyyttä ja tutkia kasvojen piirteiden yhteyttä purennan poikkeamiin sekä kasvojen estetiikkaan. Lisäksi tutkittiin purennan poikkeamien yhteyttä TMD:hen. Tutkimusjoukko koostui Pohjois-Suomen syntymäkohortti 1966 -tutkimukseen osallistuneista. Tutkimuksen aineisto kerättiin kyselomakkeiden, standardoidun kliinisen tutkimuksen ja kasvovalokuvien avulla. Profiilivalokuvien analysointi perustui pehmytkudoksen kefalometrisiin lineaari- ja kulmamittauksiin. Tässä tutkimuksessa yleisin purennan poikkeama oli sivualueen ristipurenta. Asymmetriset purennan poikkeamat olivat merkittävästi yhteydessä TMD:hen; erityisesti sivualueen ristipurenta, saksipurenta, negatiivinen horisontaalinen ylipurenta sekä nivelaseman ja keskipurennan (RCP-ICP) välisen liu’un pituus ja sivuttainen deviaatio. Negatiivisen horisontaalisen ylipurennan todettiin vaikuttavan voimakkaasti kasvojen profiiliin. ANB-kulma oli merkitsevästi yhteydessä kasvojen arvioituun viehättävyyteen. Purennan poikkeamilla näyttää olevan yhteys TMD:n oireisiin ja kliinisiin löydöksiin suomalaisessa aikuisväestössä. Horisontaalinen ylipurenta näyttää vaikuttavan kasvojen profiiliin enemmän kuin vertikaalinen ylipurenta. Kasvojen kuperuus painottuu enemmän oikomishoidon erikoishammaslääkärien näkemyksessä kasvojen estetiikasta hammaslääkäreihin ja maallikoihin verrattuna.
184

Mudanças no perfil facial de crianças com má oclusão classe II, divisão 1 decorrentes do crescimento normal e induzidas pelo bionator de Balters

Melo, Ana Cláudia Moreira [UNESP] 04 August 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-08-04Bitstream added on 2014-06-13T20:24:53Z : No. of bitstreams: 1 melo_acm_dr_arafo.pdf: 963455 bytes, checksum: 63082d3d54677a9308f74993608f95fa (MD5) / A deficiência de dados na literatura nos levou a avaliar o efeito do tratamento com o aparelho bionator de Balters no perfil facial de crianças com má oclusão Classe II, divisão 1 de Angle, excluindo as mudanças que ocorreriam com o crescimento natural. A amostra consistiu de telerradiografias de pacientes leucodermas com idades entre 6 anos e 11 meses e 11 anos e 2 meses, divididos aleatoriamente em dois grupos. Um grupo controle, composto por 11 pacientes acompanhados sem tratamento por 1 ano, e um grupo experimental, composto por 12 pacientes acompanhados durante 1 ano de tratamento, sendo que oito desses pacientes foram avaliados no 2º ano de tratamento. A seleção da amostra teve como critérios de inclusão a presença dos incisivos centrais e laterais permanentes erupcionados ou em erupção, sobremordida e sobressaliência aumentadas e ausência de apinhamento dentário e alteração transversal dos arcos. A análise cefalométrica constou de medidas tradicionais angulares e lineares, esqueléticas, dentárias e de tecidos moles, além da verificação do deslocamento individual dos pontos do perfil facial em coordenadas x e y. A aplicação do teste de Levene mostrou evidências estatísticas de semelhança inicial entre os grupos. Procedeu-se então a análise estatística que mostrou alterações significantes (p<0,05) nas variáveis indicativas de convexidade esquelética, espessura dos lábios e comprimento do lábio inferior, além de aumento da altura facial esquelética e tegumentar. Por outro lado, não foi significante a alteração na convexidade tegumentar e comprimento do lábio superior nos pacientes tratados. Pode ser concluído com base nos resultados encontrados que o uso do bionator teve efeito favorável na alteração do perfil facial, principalmente na região de lábios e na altura facial. / Literature deficiency has led us to evaluate the changes on soft-tissue profile of Class II division 1 children induced by the use of Balters bionator appliance, excluding the changes that would occur with normal growth. The sample consisted of lateral radiographies of leucoderm children from 6 years and 11 months to 11 years and 2 months, randomly divided into two groups. The control group was formed by 11 patients followed with no treatment during one year, and the experimental one was composed by 12 children, accompanied for 1 year, but eight of these patients were also evaluated 2 years after the treatment onset. The inclusion criteria were the central and lateral permanent incisors erupted or into eruption, increased overjet and overbite, and no crowding or transverse problems in the dental arches. The cephalometric analysis consisted of angular and linear skeletal, dental and soft-tissue traditional measurements as well as the verification of the individual dislocation of the soft-tissue points in x and y coordinates. Levene's test application showed statistical evidence of similarity between the groups on the beginning of the research. The statistical analysis showed significant alterations (p<0,05) of either skeletal convexity, width of upper and lower lips, and lower lip length, or skeletal and soft-tissue vertical height. On the other hand, there was no significant change on soft-tissue convexity and upper lip length in the treated patients. It can be concluded that the use of bionator had a favorable effect on soft-tissue profile, especially on lips and vertical facial height.
185

Sistema para análise viscoelástica de tecidos moles por ondas de cisalhamento usando excitação magnética e medida ultrassônica / System for viscoelastic analysis of soft tissue using magnetic excitation for generating shear waves and ultrasonic measurement

Thiago Wellington Joazeiro de Almeida 30 March 2015 (has links)
Sistemas ultrassônicos tiveram uma evolução tecnológica nos últimos anos e isso permitiu que seus recursos de hardware e software pudessem ser explorados para extrair informações, auxiliando em diagnósticos e tratamentos mais eficazes. Através da análise do comportamento mecânico de tecidos moles, técnicas como elastografia estática, vibroacustografia, elastografia transiente e elastografia remota tiveram seu papel reconhecido na complementação do diagnóstico clínico. Contudo, a propagação destas técnicas na medicina tem sido restringida pela acessibilidade às tecnologias utilizadas, ausências de parâmetros quantitativos, dificuldade da excitação em estruturas profundas e acesso a informações em níveis moleculares. Este estudo aborda o desenvolvimento de um protocolo para efetuar medidas quantitativas de viscoelasticidade em tecidos moles marcados com nanopartículas de óxido de ferro usando excitação magnética e medição ultrassônica. Ao aplicar uma força magnética pulsada em um meio fluido marcado com nanopartículas magnéticas, um movimento é induzido, gerando uma onda de cisalhamento que se propaga pelo tecido. A propagação dessa onda é mapeada usando a técnica de ultrassom pulso-eco e processamento de dados usando métricas de similaridades entre ecos (mapa de rf) consecutivos. Nos estudos realizados em mimetizadores de tecidos moles (phantom) com características mecânicas equivalentes ao tecido biológico, a amplitude de deslocamento dessas ondas é da ordem de micrometro. Através da medida da velocidade deslocamento dessa onda avaliou-se o melhor modelo reológico para quantificar os parâmetros mecânicos de viscosidade e elasticidade. Os resultados mostraram a eficiência desta técnica ao quantificar os valores viscoelásticos condizentes com a literatura e a comprovação da análise de tecidos moles marcado com nanopartículas excitadas com campo magnético de baixa intensidade, possibilitando uma avaliação em âmbito molecular em tecidos moles. / Ultrasonic systems had a technological development in recent years and allowed their hardware and software resources could be exploited to extract information, assisting in more effective diagnosis and treatment. Through the mechanical behavior analysis of soft tissue techniques such as static elastography, vibroacoustography, transient elastography and remote elastography had recognized role in complementing clinical diagnosis. However, the spread of these techniques in medicine has been restricted by accessibility to the technologies used, quantitative parameters absences, difficulty of deep structures access and information on molecular levels. This study addresses the development of a protocol to make quantitative measurements of viscoelastic soft tissue labeled with iron oxide nanoparticles using magnetic excitation and ultrasonic measurement. By applying a pulsed magnetic force in a fluid medium labeled with magnetic nanoparticles, a motion is induced, generating a shear wave that propagates through the tissue. The propagation of this wave is mapped using the pulse-echo ultrasound technique and data processing using similarities measurements between echoes (rf map) consecutive. In studies of soft tissue-mimicking phantom with mechanical properties equivalent to the biological tissue, the displacement amplitude of these waves is of micrometer order. By measuring the shear wave velocity, it was evaluated the best rheological model for quantifying mechanical parameters of viscosity and elasticity. The results showed the efficiency of this technique to quantify the viscoelastic values consistent with the literature and the evidence of soft tissue analysis labeled excited nanoparticles with low intensity magnetic field, providing an assessment on the molecular level in soft tissues.
186

Investigação do acomentimento dos tecidos moles em individuos portadores de disturbios osteomusculares relacionados ao trabalho (DORT) / Investigation of soft tissue involvement in individuals hearing work related musculoskeletal disorders (WMSD)

Vieira, Vera Lucia Martinez 24 February 2006 (has links)
Orientador: Jose Inacio de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-06T17:45:11Z (GMT). No. of bitstreams: 1 Vieira_VeraLuciaMartinez_D.pdf: 20761528 bytes, checksum: e07d8874c527947dd41ebd43cf4e86a1 (MD5) Previous issue date: 2006 / Resumo: A pesquisa teve como objetivo propor um protocolo de investigação de alterações dos tecidos moles, perceptíveis à palpação em pacientes com LER/DORT. A metodologia proposta verificou, por meio de um estudo preliminar, a região a ser avaliada, a demarcação anatômica e o equipamento com especificação a ser utilizado na realização das medidas. Os sujeitos da pesquisa foram selecionados obedecendo a critérios que permitiam a verificação das alterações nos tecidos moles. A população avaliada constituiu-se de 20 homens com média de idade de 41,4 anos, massa corporal média de 76 kg, altura média de 1,71 m e índice de massa corporal (IMC) médio de 26,02 kg/m2; e de 20 mulheres com idade média de 37,9 anos, massa corporal média de 62,7 kg, altura média de 1,64 m e índice de massa corporal (IMC) médio de 23,6 kg/m2. Por meio de técnica palpatória, foi examinada a região do antebraço do membro superior dominante de dez homens e dez mulheres adoecidos com LER/DOR, e dez homens e dez mulheres sem adoecimento no membro superior, porém acometidos de lesão em outra área Os resultados foram submetidos ao cálculo da significância (p < 0,05) e determinou-se a variabilidade das amostras, testando hipóteses. Estes se apresentaram estatisticamente significantes no grupo de mulheres com adoecimento (63 cm) em comparação com as mulheres sem adoecimento (75 cm), mostrando diminuição no deslocamento tecidual na região muscular (terço proximal) do antebraço do membro superior dominante em mulheres com lesão. O fato de se obter resultados significativos no grupo de mulheres suscitou a discussão sobre o adoecimento e suas conseqüências na população trabalhadora feminina. Estudos específicos sobre gênero mostram que os riscos são maiores em mulheres, porém a distribuição da morbidade não está vinculada ao gênero. O experimento visou à elaboração de um protocolo de investigação quantitativa das aderências em tecidos moles e, ainda à comprovação metodológica da coleta desses dados. Porém verificou-se, nos resultados obtidos, possibilidades de se estabelecer parâmetros que possam, de maneira simplificada, mostrar possíveis alterações nos tecidos moles A importância prática desta investigação está na utilidade do dado quantificado para complementar e reafirmar avaliações osteomusculares para fins de diagnósticos de incapacidade em pacientes com LER/DORT. A quantificação pode auxiliar no discernimento subjetivo que envolve a avaliação desses pacientes / Abstract: The research aimed at proposing an investigation protocol for palpable soft tissues in RSI patients Through a preliminary study, the proposed methodology checked the area to be evaluated, the anatomical delimitation of this area as well as the equipment to be used for measurement and specifications. Research subjects were selected pursuant to criteria that allow for the checking of soft tissue abnormalities. The subject population consisted of 20 males averaging 41.4 years of age, 76 kg. body mass average, 1.71 m. average height and average Body Mass Index (BMI) equal to 26.02 kgm2, and 20 females averaging 37.9 years of age, 62.7 kg body mass average, 1.64 m. average height and average Body Mass Index (BMI) equal to 23 6 kgm2 Through palpation technique, the forearm area of the dominant superior limb was examined. The subjects were 10 men and 10 women diagnosed of RSI in the area under scrutiny, and 10 men and 10 women without RSI diagnosis in such area, although injured in other areas. The results were submitted to significance calculation (p < 0.05) and the variability of the samples was determined through hypothesis test These showed to be statistically significant in the positive RSI diagnosis women's group (63 cm) as compared to the healthy women sample (75 cm), the first subjects presenting tissues displacement decrease at the muscle area (proximal third) of the upper limb forearm in positive RSI diagnosis women's group. The issue of significant results having been found in the women's group raised the point of RSI in the female working population. Specific studies on gender show that risks are higher in women, however, the morbidity distribution is not linked to gender. The experiment aimed at preparing a protocol for quantitative investigation of soft tissue adherence and providing methodologic proof of the collection of those data. However, in the obtained results we saw possibilities of establishing parameters that could, in a simplified way, show possible changes in soft tissues. This investigation importance to everyday use is that this quantified datum complements and reasserts osteo-muscular evaluations for disability diagnoses of RSI patients. This quantification may aid to the subjective discernment required to the evaluation of RSI patients / Doutorado / Saude Coletiva / Doutor em Saude Coletiva
187

Avaliação clínica e micológica de pacientes portadores de próteses totais sobre implantes / Clinical and mycological evaluation of patients with full-arch implant-supported fixed prostheses

Ricardo Ramalho Vecchiatti 07 February 2018 (has links)
Introdução: Considerando-se a crescente tendência da utilização de próteses sobre implantes tanto em nossa população quanto em âmbito mundial, ganha importância o estudo das diversas condições envolvidas na longevidade e funcionalidade dessas peças para os indivíduos em geral. Objetivo: Determinar a ocorrência de alterações patológicas associadas a próteses totais implantadas e correlacioná-las a variáveis individuais, das peças protéticas e à participação de leveduras do gênero Candida nesses indivíduos. Metodologia: Pacientes portadores de próteses sobre implantes foram avaliados no momento da remoção das peças para controle e manutenção, após anuência com os termos do consentimento livre e esclarecido. Os participantes tiveram seus fluxos salivares totais avaliados inicialmente. Após a remoção das próteses, as peças foram avaliadas tecnicamente (próteses, implantes, parafusos e abutments), a boca examinada clinicamente, as condições da mucosa subjacente às próteses foram anotadas, e eventuais lesões associadas às próteses foram avaliadas e tratadas. Paralelamente foi realizada coleta de material para exame micológico de dois sítios - mucosa sob a prótese e base da prótese. O material foi coletado com auxílio de swabs e transferido a placas com meio de cultura diferencial (Chromagar®) para observação de crescimento e identificação de leveduras. Resultados: Foram coletados dados referentes a 91 participantes e 102 próteses sobre implantes. Trinta e quadro homens e 57 mulheres com idade média de 66,6 anos. Quatro overdentures, 72 protocolos inferiores e 26 superiores. Nenhum participante apresentou hipossalivação. Candida spp foram identificadas em 70,3% das arcadas inferiores e 85,7% das arcadas superiores. O tempo de uso das próteses interferiu na porcentagem de identificação das leveduras. Candida albicans foi a principal espécie identificada (93% dos casos positivos). Outras espécies identificadas foram: Candida glabrata, C. kruzei e C. tropicalis. Técnicas de higienização adicionais à escovação convencional reduziram a contaminação pelos fungos, enquanto hábitos de fumar ou consumir bebidas alcoólicas a aumentaram. Inflamação em mucosa relacionou-se positivamente à presença de Candida em mucosa e próteses. Oito participantes foram submetidos a intervenções cirúrgicas para remoção de processos proliferativos inflamatórios (8,8%). Foram avaliados 532 implantes, registrando-se perda de 1,13% deles e necessidade de reaperto em 271 parafusos (50,1%). Os dados foram analisados de forma descritiva e submetidos a testes estatísticos adequados ao tipo de dados obtidos. Conclusões: Os resultados obtidos nesta investigação sugerem que os cirurgiões dentistas que trabalham na área da Implantodontia devem rever seus protocolos de orientação aos pacientes e regimes de manutenção das próteses totais sobre implantes, a fim de manter a saúde dos indivíduos, prevenir lesões inflamatórias nos tecidos orais e proporcionar longevidade à reabilitação. / Introduction: Considering the increasing tendency of the use of prostheses on implants in both our population and worldwide, it is important to study the several conditions involved in the longevity and functionality of these parts for individuals in general. Aim: To determine the occurrence of pathological changes associated with full-arch implant-supported fixed prostheses and to correlate them with individual variables, prosthetic specimens and the participation of Candida yeasts in these individuals. Methodology: Patients with full-arch implant-supported fixed prostheses and overdentures were evaluated at the time of removal of the parts for control and maintenance, after consent with the terms of free and informed consent. The participants had their total salivary flows initially evaluated. After the removal of the prosthesis, the pieces were evaluated technically (prostheses, implants, screws and abutments), the mouth examined clinically, the conditions of the mucosa underlying the prostheses were noted, and any lesions associated with the prostheses were evaluated and treated. In parallel, material was collected for mycological examination of two sites - mucosa under the prosthesis and base of the prosthesis. The material was collected with the help of swabs and transferred to plates with differential culture medium (Chromagar®) for observation of growth and identification of yeasts. Results: Data were collected on 91 participants and 102 implants. Thirty-one men and 57 women with mean age of 66.6 years. Four overdentures, 72 in the lower arch and 26 in the upper arch. No participant presented hyposalivation. Candida spp. were identified in 70.3% of the lower arches and 85.7% of the upper arches. The time of use of the prostheses interfered in the percentage of identification of the yeasts. Candida albicans was the main species identified (93% of the positive cases). Other species identified were: Candida glabrata, C. kruzei and C. tropicalis. Hygiene techniques in addition to conventional brushing reduced fungal contamination, while smoking or drinking increased. Inflammation in mucosa was positively related to the presence of Candida in mucosa and prostheses. Eight participants underwent surgical interventions to remove proliferative inflammatory processes (8.8%). A total of 532 implants were evaluated, with a loss of 1,13% of them and the need to re-tighten 271 screws (50.1%). Data were analyzed descriptively and submitted to statistical tests appropriate to the type of data obtained. Conclusions: The results obtained in this research suggest that dental surgeons working in the implantology area should review their patient orientation protocols and maintenance of full-arch implant-supported fixed prostheses in order to maintain the health of individuals, prevent inflammatory lesions in tissues oral and provide longevity to rehabilitation.
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\"Estudo comparativo da cefalometria do perfil tegumentar com base na análise facial de Arnett relacionada à horizontal verdadeira com a realizada a partir do plano de Frankfurt horizontal\" / A comparative study of the cephalometric of the soft tissue profile based on Arnett´s facial analysis in relation to the true horizontal as this has been put into practice starting from the Frakfurt horizontal plane.

Cláudia Maria Romano de Sousa 23 March 2007 (has links)
Nesta pesquisa foi comparada a diferença das medidas obtidas utilizando-se a análise cefalométrica do perfil tegumentar tendo como base a análise facial de Arnett relacionada à Horizontal Verdadeira com a análise cefalométrica do perfil tegumentar feita a partir do Plano de Frankfurt. Utilizamos 140 radiografias cefalométricas requisitadas como parte de documentação ortodôntica, obtidas de pacientes com idade variando de 06 a 49 anos, sendo 64 do sexo masculino e 76 do sexo feminino, pertencentes ao arquivo do IOM - (Instituto de Odontologia Multidisciplinar) ? RJ. As radiografias cefalométricas em norma lateral foram obtidas pelo mesmo operador, obedecendo ao protocolo adotado pelo IOM. Todos os pacientes foram orientados a assumir a Posição Natural da Cabeça, tendo como referência um espelho posicionado a frente e a Linha Vertical Verdadeira foi obtida por meio da utilização de um fio metálico unido à um prumo de chumbo, posicionado próximo à margem anterior do chassi porta-filme, de forma que apareça à frente do perfil tegumentar do paciente. A partir das medidas lineares obtidas nas Análises Cefalométricas dos Tecidos Moles, foram realizadas análises estatísticas visando dois objetivos: comparar as medidas de A à I obtidas nos traçados (um utilizando como referência uma perpendicular ao Plano Horizontal de Frankfurt e o outro à Linha Vertical Verdadeira) e analisar os resultados comparativamente. Após a análise estatística (Kolmogorov-Smirnov, para distribuição normal de dados; t-Student para amostras emparelhadas e teste não paramétrico de Wilcoxon) e a interpretação dos resultados obtidos, concluímos que houve diferenças significantes entre as formas de medidas das variáveis A, B, C, D, F, G e I, pois o valor do nível descritivo (p-valor) se apresentou abaixo de 0,05. Entretanto para as medidas E e H o valor do nível descritivo (p-valor) se apresentou maior que 0,05, demonstrando não haver diferenças significantes entre as formas dessas medidas. As correlações entre as medidas apresentadas estabelecidas pela análise facial de Arnett, de acordo com este estudo, não deverão ser utilizadas em pacientes que se submeteram à radiografias cefalométricas realizadas a partir do Plano Horizontal de Frankfurt, salvo no caso da distância interlabial, representada pela medida H, que além de não apresentar diferenças significantes neste estudo, não tem, segundo a análise de Arnett, correlação com nenhuma outra medida. / In this research a comparison was made between the differences in measurements obtained using the soft tissue profile?s cephalometric analysis based on Arnett?s facial analysis related to the true vertical with the cephalometric analysis of soft tissue profile based on the Frankfurt Plan. A total of 140 lateral cephalometric radiographs were used as part of the orthodontic documentation, taken from patients whose ages ranged from 06 to 49 years of age, of these 64 males and 76 females, being part of the files of the IOM (Instituto de Odontologia Multidisciplinar do Rio de Janeiro). The lateral cephalometric radiographs were obtained from the same operator obeying the protocols adapted by the IOM. All patients were oriented to place themselves in the Natural Head Posture using, as a reference, a mirror in front of then and the true vertical line was obtained using a metal wire and a plumb-line, placed close to the frontal chassis of the film chamber, in such a way that it appears in front of the soft tissue profile of the patient. Parting from the lineal measurements obtained from the Cephalometric Analyses of the Soft Tissues statistical analyses were made relating to two objectives: to compare the measurements from A to I obtained from the drafts/ sketches (one using as it reference a perpendicular to the Frankfurt Horizontal Plane and the other the True Vertical Line), comparatively analyse these results. After the statistical analysis (Kolgomorov Smirnov) for a normal data distribution: t-student for matched pairs and the no-parametric Wilcanox test) and the analysis of the results obtained, it was concluded that there were significant differences between the forms of the measurements of the variables A, B, C, D, F, G and I since the descriptive value (p-value) was below 0,05. The measurements for E and H, however, being over 0,05, showing than there were no significant differences between these forms of measurement. The correlation between the demonstrated measurements established by Arnett?s facial analysis, in accordance with this study, should not be used in patients who have undergone lateral cephalometric radiograph initiated on the basis of the Frankfurt Horizontal Plane except in the case of interlabial distance represented by the measurement H, which even differences in this study, does not have, according to Arnett?s studies, correlations with any other measurements.
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Avaliação da microdensidade vascular como fator prognóstico em sarcomas de tecidos moles em pequenos animais / Microvessel density evaluation as a prognostic factor in canine and feline soft tissue sarcomas

SILVEIRA, Matheus Folgearini 20 May 2009 (has links)
Made available in DSpace on 2014-08-20T14:37:57Z (GMT). No. of bitstreams: 1 dissertacao_matheus_folgearin_silveira.pdf: 274999 bytes, checksum: 17765fa39ad1a46f221283537ac0adae (MD5) Previous issue date: 2009-05-20 / Soft tissue sarcomas are mesenchymal origin neoplasms collectively classified according to histological characteristics and biological behaviour similiarities. Various neoplasms are included in this major group, as fibrosarcoma, hemangiosarcoma, peripheral nerve sheath tumor, myxosarcoma, liposarcoma, leiomyosarcoma, rhabdomiosarcoma, malignant fibrous histiocytoma, synovial cell sarcoma and undifferentiated sarcoma. The microvessel density measure has been applied to investigate tumor angiogenesis in many neoplasms. The objectives of this study were to evaluate de microvessel density in canine and feline soft tissue sarcomas and compare the general vessel measurement area and intense vascular areas hot spot. Those data were compared to usually applied prognostic factors like mitotic index, necroses presence and amount and cellular differentiation. Soft tissue sarcomas were collected in Laboratório Regional de Diagnóstico da Universidade Federal de Pelotas from 1978 to 2008 among canine and feline necropsies and biopsies. In a total of 1668 neoplasms cases during this period, 100 were soft tissue sarcomas, 87 canine and 13 feline. Sex prevalence was not observed in the analyzed species. The major prevalence in canine were hemangiosarcomas (n=34) and fibrosarcomas (n=20), being the mongrel dogs (n=35) most. The large breeds presented major frequence (n=22), followed by medium size (n=16) and small sized breeds (n=9). . In feline population, there were not accentuated prevalence, exciding hemangiosarcomas (n=4) and fibrosarcomas (n=4). In those 100 cases, 39 paraffin blocks were obtained, being 36 canine and 3 feline, mostly mongrel specimens, with 9,21(±2,99) medium age. The general vascular and hot spot areas were significantly correlated (r2=0,98; p<0,01). The mitotic index between areas were in those areas (r2=0,95, p<0,01). Hemangiosarcomas presented major vascular media in the techniques, followed by muscular sarcomas and fibrosarcomas (p<0,05). The microvessel density in soft tissue sarcomas do not present correlation to other prognostic factor usually applied. Hot spot areas can be utilized to determine the vascular degree and mitotic index in soft tissue sarcomas. / Os sarcomas de tecidos moles são neoplasmas de origem mesenquimal classificados coletivamente devido a características histológicas e comportamento biológico similares. Vários neoplasmas estão incluídos neste grande grupo, como fibrossarcoma, hemangiossarcoma, tumor de bainha de nervo periférico, mixossarcoma, lipossarcoma, leiomiossarcoma, rabdomiossarcoma, histiocitoma fibroso maligno, sarcoma sinovial e sarcoma indiferenciado. A mensuração da densidade vascular tem sido utilizada para investigar a angiogênese tumoral em diferentes neoplasmas. Este estudo teve como objetivo a determinação da microdensidade vascular de sarcomas de tecidos moles caninos e felinos através da comparação entre a mensuração geral vascular e áreas de intensa proliferação hot spot. Estes dados foram comparados a fatores prognósticos usualmente empregados, como índice mitótico, presença e quantidade de necrose e diferenciação celular. Os sarcomas de tecidos moles foram resgatados dos arquivos do Laboratório Regional de Diagnóstico da Universidade Federal de Pelotas entre 1978 a 2008 dentre necropsias e biópsias caninas e felinas. Num total de 1668 neoplasmas deste período, 100 eram sarcomas de tecidos moles, sendo 87 caninos e 13 felinos. Não se observou prevalência de sexo nas espécies analisadas. Em caninos, a maior prevalência foi de hemangiossarcomas (n=34) e fibrossarcomas (n=20), sendo os sem raça definida (n=35) os mais acometidos. Os animais de porte grande apresentaram maior freqüência (n=22), seguidos pelos de porte médio (n=16) e de porte pequeno (n=9). Em felinos não houve uma prevalência acentuada, destacando-se os hemangiossarcomas (n=4) e fibrossarcomas (n=4). Destes 100, obtiveram-se blocos de 39 casos, sendo 36 caninos e 3 felinos, em sua maioria sem raça definida nas duas espécies, com idade média observada foi de 9,21(±2,99 anos). A mensuração vascular geral e de áreas hot spot apresentaram correlação significativa (r2=0,98; p<0,01). O índice mitótico nas duas áreas observadas foram significativas (r2=0,95, p<0,01). Os hemangiossarcomas apresentaram maior média vascular nas duas técnicas, seguidos pelos sarcomas musculares e fibrossarcomas (p<0,05). Houve diferença entre os hemangiossarcomas e os fibrossarcomas, e os sarcomas musculares não diferiram desses (p<0,05). A microdensidade vascular em sarcomas de tecidos moles não apresentou correlação com outros fatores empregados usualmente. A visualização de campos hot spot pode ser utilizada para determinar o grau vascular e índice mitótico.
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Identification of corneal mechanical properties using optical tomography and digital volume correlation / Identification de la mécanique de la cornée par la tomographie optique et la corrélation de volume numérique

Fu, Jiawei 26 March 2014 (has links)
Ce travail présente une méthodologie efficace pour mesurer le champ de déformation total en 3-D des tissus mous semi-transparents et diffusant la lumière, tels que la cornée de l'œil vertébré. Cela a été obtenu en utilisant la tomographie par cohérence optique couplée avec la corrélation volumique numérique sur des fantômes en caoutchouc de silicone et de la cornée porcine. Des tests de traction et des tests d'inflation postérieure ont été étudiés. Avant ces tests, l'effet du bruit et la décorrélation des speckles due à la déformation sont d'abord étudiés en utilisant des méthodes expérimentales et numériques. Le biais d'interpolation dans les résultats de déformation a été analysé. Deux approches efficaces ont été prises pour réduire le biais d'interpolation. Pour extraire les paramètres constitutifs des mesures de déformation 3-D, la méthode des champs virtuels a été étendue en 3-D. Les champs virtuels définis manuellement et les champs virtuels optimisés par morceaux ont été développés et comparés entre eux. Des efforts ont également été déployés pour corriger les distorsions induites par réfraction dans les reconstructions de la tomographie par cohérence optique. Des tests d'inclinaison des différents fantômes de silicone ont été introduits afin d’évaluer la performance de la méthode pour corriger les reconstructions distordues / This work presents an effective methodology for measuring the depth-resolved 3-D full-field deformation of semitransparent, light scattering soft tissues such as vertebrate eye cornea. This was obtained by performing digital volume correlation on optical coherence tomography volume reconstructions of silicone rubber phantoms and porcine cornea samples. Both the strip tensile tests and the posterior inflation tests have been studied. Prior to these tests, noise effect and strain induced speckle decorrelation were first studied using experimental and simulation methods. The interpolation bias in the strain results has also been analyzed. Two effective approaches have been introduced to reduce the interpolation bias. To extract material constitutive parameters from the 3-D full-field deformation measurements, the virtual fields method has been extended into 3-D. Both manually defined virtual fields and the optimized piecewise virtual fields have been developed and compared with each other. Efforts have also been made in developing a method to correct the refraction induced distortions in the optical coherence tomography reconstructions. Tilt tests of different silicone rubber phantoms have been implemented to evaluate the performance of the refraction correction method in correcting the distorted reconstructions

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