Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-19T11:28:37Z No. of bitstreams: 2 Dissertação - Pedro Henrique Moreira Paulo Tolentino - 2018.pdf: 3401198 bytes, checksum: e64f80a13a617556faa86089c4579b90 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-19T11:29:34Z (GMT) No. of bitstreams: 2 Dissertação - Pedro Henrique Moreira Paulo Tolentino - 2018.pdf: 3401198 bytes, checksum: e64f80a13a617556faa86089c4579b90 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-19T11:29:34Z (GMT). No. of bitstreams: 2 Dissertação - Pedro Henrique Moreira Paulo Tolentino - 2018.pdf: 3401198 bytes, checksum: e64f80a13a617556faa86089c4579b90 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-01 / The objective of this study was to evaluate if periodontal training and the time and place of formation and the training of professionals in Bioethics and Forensic Dentistry would influence the decision making in relation to indicating the exodontia of periodontally affected teeth and the type of rehabilitation suggested in patients with partial edentulism, identifying the clinical and social criteria that would directly interfere with this choice. For this purpose, a questionnaire was applied to general dental surgeons and periodontal specialists, with questions regarding age, time and training institution, and decision making for four (4) clinical cases illustrated as to the factors of interest for the study. 423 questionnaires were distributed, with a rate of return of 35,46%. Of these, 31.3% were periodontists and 68.7% were general clinical. 82% had less than 15 years of training and 18% had more than 15 years. Regarding the clinical decision for case #1, 42% did not indicate any extraction for the upper arch and 56% had the same decision for the inferior arch. A statistically significant difference was observed between periodontists and general practitioners (p<0.05). In case #2, 57.3% and 92.7% of the participants indicated exodontia of up to 3 teeth for the upper and lower arches, respectively. A statistically significant difference (p<0.05) was observed in relation to the indication for the remnants as a function of the participants' training time. Regarding case #3, only 1 participant, who was periodontist, indicated extraction for 2 teeth from the upper arch. For the lower arch, 48% indicated extraction of up to 3 teeth, and statistically significant differences were observed in relation to the formation time and the number of teeth indicated for extraction (p<0.05). In case #4, 83.3% of the participants indicated exodontia of all remnants. Regarding the type of rehabilitation, the removable partial denture was the most appropriate option for cases #1 and #2 for both arches, with a statistically significant difference between specialists and non-specialists for case #2, the periodontists indicated more frequently prostheses implant-supported (p<0.05). For the lower arch of case #3, rehabilitation with implant-supported prosthesis was the most chosen option (75.3%), with a statistically significant difference between specialists and general practitioners (p<0.05). In case #4, the participants indicated more muco-supported total prosthesis, for upper (89.3%) and lower arch (63.3%), without significant statistical differences (p>0.05). Regarding the clinical and social criteria that guided decision making, the most frequent reason to justify the indication of extraction in all cases was the severity of patients periodontal disease. The results showed that clinical decision making in relation to the proposed cases was influenced by the specialty and the training time of the participants. In general, periodontists and professionals with shorter training periods recommended fewer extractions, and there was a greater tendency among specialists to indicate implant-supported prostheses. The severity of periodontal disease was a more relevant criterion than social issues and the patient's willingness to decide to indicate exodontia. / O objetivo desse trabalho foi avaliar se a formação em Periodontia, o tempo e local de formação e a formação dos profissionais em Bioética e Odontologia Legal influenciariam na tomada de decisão em relação à indicar a exodontia de dentes periodontalmente afetados e ao tipo de reabilitação sugerida em casos de pacientes que apresentam edentulismo parcial, identificando os critérios clínicos e sociais que interfeririam diretamente nesta escolha. Para isso, foi aplicado um questionário a Cirurgiões-dentistas clínicos gerais e a especialistas em Periodontia, com questões referentes à idade, tempo e instituição de formação, e tomada de decisão para 04 (quatro) casos clínicos ilustrados quanto aos fatores de interesse para o estudo. Foram distribuídos 423 questionários, com uma taxa de retorno de 35,46%. Destes, 31,3% eram periodontistas e 68,7% clínicos gerais. 82% tinham menos de 15 anos de formação e 18% mais de 15. Em relação a decisão clínica para o caso 1, 42% não indicaram nenhuma extração para o arco superior e 56% tiveram a mesma decisão para o inferior. Foi observada uma diferença estatisticamente significante entre os periodontistas e os clínicos gerais (p<0,05). No caso 2, 57,3% e 92,7% dos participantes indicaram exodontia de até 3 dentes para os arcos superior e inferior respectivamente. Foi observada uma diferença estatisticamente significante (p<0,05) em relação a indicação para os remanescentes em função do tempo de formação dos participantes. Em relação ao caso 3, apenas 1 participante, que era periodontista indicou exodontia para 2 dentes do arco superior. Já para o arco inferior, 48% indicaram extração de até 3 dentes, sendo observada diferenças estatísticas relevantes em relação ao tempo de formação e a quantidade de dentes indicados para extração (p<0,05). No caso 4, 83,3% dos participantes indicaram exodontia de todos os remanescentes. Quanto ao tipo de reabilitação, a prótese parcial removível foi a opção mais indicada para os casos 1 e 2 para ambos os arcos, havendo uma diferença estatisticamente significante entre especialistas e não especialistas para o caso 2, sendo que os periodontistas indicaram com maior frequência próteses implanto-suportadas (p<0,05). Para o arco inferior do caso 3, a reabilitação com prótese implanto-suportada foi a opção mais escolhida (75,3%), havendo uma diferença estatisticamente significante entre os especialistas e os clínicos gerais (p<0,05). No caso 4, os participantes indicaram mais a prótese total muco-suportada, tanto para o arco superior (89,3%), como para o inferior (63,3%), sem diferenças estatísticas significantes (p>0,05). Com relação aos critérios clínicos e sociais que nortearam à tomada de decisão, o motivo mais alegado para justificar a indicação de extração em todos os casos, foi a gravidade da doença periodontal dos pacientes. Os resultados demonstraram que a tomada de decisão clínica frente aos casos propostos, sofreu influência da especialidade e do tempo de formação dos participantes. De um modo geral, os periodontistas e profissionais com menor tempo de formação recomendaram menos exodontias, e houve uma tendência maior por parte dos especialistas em indicar próteses implanto-suportadas. A gravidade da doença periodontal foi um critério mais relevante do que questões sociais e vontade do paciente para a decisão de indicar exodontias.

Próteses auriculares tem o objetivo de proporcionar uma maior confiança a pacientes com perdas parciais ou totais da orelha. A aparência realista de uma prótese é fator fundamental para a recuperação psicossocial dos pacientes, pois auxilia na dissimulação da perda. O procedimento convencional de elaboração de próteses auriculares envolve o trabalho de um especialista que utiliza processos manuais para recriar a forma singular de uma orelha. Este é um processo lento, complexo e naturalmente pode ocasionar imperfeições. Este estudo apresenta um procedimento que, a partir de exames de imagem, utiliza técnicas computacionais de reconstrução, espelhamento e inversão de modelos tridimensionais para manufatura aditiva (impressão 3D) de moldes. Os resultados mostram que a prótese elaborada utilizando o processo exibe alto grau de realismo, apresentando 97,8% de similaridade dimensional comparada com a orelha sã do paciente. / Auricular prostheses are intended to provide confidence to patients with partial or total loss of the ear. The realistic appearance of a prosthesis is a key factor for the psychosocial recovery helping in dissimulation of loss. The standard procedure of auricular prosthesis design involves the work of an expert using manual processes to recreate the complex shape of the ear. This slow and complex process can easily lead to imperfections. This study presents a procedure that starting from an image exam uses computational techniques of reconstruction, mirroring and inversion of three-dimensional models for additive manufacturing (3D printing) of molds. The results show that the designed prosthesis using the process has a high level of realism, with 97.8% of similarity compared to the healthy ear of the patient.

O Brasil, à semelhança de outros países, está envelhecendo rapidamente. Os indivíduos com mais de 60 anos compõem hoje o segmento que mais cresce em termos proporcionais, mostrando um incremento da ordem de 500%, em 40 anos. A estimativa para o ano de 2020 é de que o Brasil tenha em torno de 32 milhões de indivíduos idosos, e desta população, uma parcela significativa será parcial ou totalmente desdentada, necessitando de aparelhos protéticos. Apesar da Odontologia apresentar avanços científicos notáveis na reabilitação da saúde bucal, muitos ainda usarão estes aparelhos. Sabe-se que o uso contínuo de próteses pode propiciar o desenvolvimento da estomatite protética, cuja etiologia é multifatorial, destacando-se principalmente a má higiene bucal e da prótese, e geralmente associada à presença de Candida albicans. Desta forma, há necessidade de se propor um método de desinfecção, que se mostre eficaz, que seja seguro quanto à toxicidade, que represente baixo risco ocupacional, que seja de fácil manuseio e que não interfira nas propriedades dos materiais utilizados na confecção destes aparelhos. Portanto, a proposição deste trabalho foi avaliar a influência de dois métodos de desinfecção, nas propriedades das resinas acrílicas empregadas na confecção das próteses.As propriedades avaliadas foram: resistência e módulo de flexão, resistência ao impacto Izod, microdureza Knoop, rugosidade, massa específica e grau de inchamento, grau de conversão do monômero, temperatura de transição vítrea, sorção e solubilidade. Os corpos de prova foram confeccionados de acordo com os requisitos de cada ensaio, tanto para os grupos controle (sem tratamento), quanto para os tratados (submetidos a um dos processos de desinfecção). Os tratamentos de desinfecção consistiram de: a) irradiação com energia de microondas na potência de 840 W, durante 1 minuto; b) imersão em ácido peracético durante 5 minutos. A eficácia da desinfecção foi avaliada através de ensaios microbiológicos que consistiram em verificar o crescimento no meio de cultura e na superfície do corpo de prova de Candida albicans, após a desinfecção dos corpos de prova, previamente contaminados com uma cepa conhecida do fungo (ATCC 10231). Como as resinas acrílicas são materiais muito utilizados em todas as áreas de atuação da Odontologia, o conhecimento das suas propriedades é de interesse do cirurgião-dentista. As resinas acrílicas tipo 1 (de termopolimerização), tipo 2 (quimicamente ativada) e tipo 5 (ativada por microondas) foram avaliadas neste trabalho. Os resultados mostraram que as resinas acrílicas tipo 1 e tipo 5 apresentam valores semelhantes em todas as propriedades analisadas. A resina acrílica tipo 2 apresentou valores inferiores àqueles encontrados nas tipo 1 e 5. O ciclo de polimerização com melhores resultados foi aquele proposto pelo respectivo fabricante daresina acrílica. A presença de fibras de nylon e de corante não influenciou as propriedades da resina acrílica tipo 5. Das técnicas de desinfecção, a imersão em ácido peracético apresentou os melhores resultados para todas as propriedades avaliadas ao longo do tempo de 20 meses. Por outro lado a irradiação de microondas, a longo prazo, apresentou os piores resultados para todas as propriedades avaliadas. Ambas as técnicas de desinfecção foram eficazes do ponto de vista microbiológico. Mas, para o uso prolongado, a técnica de desinfecção com ácido peracético pode ser recomendada com toda a segurança, no que diz respeito às propriedades avaliadas neste trabalho. / Brazil, similar to other countries, is aging quickly. The individuals with more than 60 years old compose today the segment that more grows in proportional terms, showing an increment of about 500% in 40 years. The estimate for 2020 is that Brazil has around 32 million elderly and a significant parcel of them will be partial or totally toothless, needing prosthetic equipments. In spite of notable scientific advance in the rehabilitation of the oral health, many people still will use these equipments. The continuous use of the prosthesis can propitiate the development of denture stomatitis, whose etiology is multifactorial, being generally, associated to the presence of fungus Candida albicans. Bad oral hygiene and prosthesis is still distinguished as factor of risk. Therefore, it very necessary for the elderly a efficient, safe and easy handling method of disinfection with low occupational risk and that doesn’t intervene with the properties of the materials used in the confection of these prosthetic equipments. The aim of this work is to evaluate the influence of two disinfection methods on the properties of acrylic resin used in the confection of dental prosthesis. Samples had been confectioned in accordance with the requirements of each test for the control groups (without treatment), as for the treated (submitted to one of the disinfection process). The evaluated properties had been resistance and module of flexure, Izod impact, Knoop microhardness, rugosity, specific mass and degree of swelling, degree of conversion of monomer, glass transition temperature, sorption and solubility. The treatments of disinfection had consisted of: a) irradiation with energy of microwaves, in the power of 840 W, during 1 min, or b) immersion in peracetic acid during 5 min. The effectiveness of the disinfection was evaluated by means of microbiological tests, in which was verified the occurrence of growth of Candida albicans through of culture and sample surface. For that, the samples were previously contaminated with one type of fungus (known as ATCC 10231) and, after, submitted to one of the two considered processes of disinfection. The work was studied the behavior of three commercial acrylic resins of dental use: acrylic resins of thermal polymerization, self-polymerization and polymerization for energy of microwaves (type 1, 2 and 5 respectively) from two different suppliers The results had shown that the acrylic resins of type 1 and type 5 presented similar values in all the analyzed properties. The acrylic resins of type 2 had also similar values in all the properties, but statistically lower than ones of type 1 and 5. The best polymerization cycle, which did not modify the resin properties, was that one considered by the respective manufacturer of the acrylic resin. The nylon fiber presence and colouring did not influence the properties of the acrylic resin of type 5. The first irradiation with microwaves significantlyincreased the evaluated properties and the first immersion in peracetic acid did not modify these properties, in comparison to the control groups. After 20 months, the immersion in peracetic acid did not modify the properties of the material, while the microwave irradiation showed alterations in some properties. Both disinfection techniques had been efficient of the microbiological point of view. On the basis of these results, can be concluded that the microwave irradiation after the polymerization of the material (first cycle), can be recommended, since it increased all the values of the evaluated properties, specially to the conversion degree monomer/polymer. Nevertheless, for prolonged use, the disinfection by means of the immersion in peracetic acid must be recommended, it is efficient for elimination of fungal microorganism and security, characterized for the maintenance of the properties of the acrylic resin evaluated in this work.

Introdução: Embora a avaliação perceptivo-auditiva seja reconhecida como padrão ouro na avaliação clínica da fala de pacientes com fissura palatina e/ou disfunção velofaríngea (DVF), ela pode ser influenciada por inúmeros fatores, dada a sua subjetividade. A avaliação instrumental, como a técnica fluxo-pressão, pode complementar os achados de fala e da função velofaríngea em indivíduos que utilizam prótese de palato com obturador faríngeo para o tratamento da DVF. Objetivos: Descrever e comparar os resultados das medidas da área velofaríngea, por meio da técnica fluxo-pressão, e do julgamento da ocorrência do EAN durante a repetição de palavras com a consoante p e da emissão da palavra papai, durante a realização do Teste de Emissão de Ar Nasal (TEAN), nas condições com e sem prótese de palato e verificar a relação entre a ocorrência do EAN e a classificação da função velofaríngea, nas condições com (CP) e sem (SP) prótese de palato. Material e Métodos: Foi realizado um estudo observacional transversal de uma amostra de conveniência de 94 pacientes com diagnóstico de insuficiência velofaríngea que utilizavam prótese de palato com obturador faríngeo. A classificação do tipo de função velofaríngea (adequada, adequada-marginal, marginal-inadequada e inadequada) foi realizada a partir da medida da área velofaríngea obtida pela técnica fluxo-pressão, durante a produção da consoante p inserida na sílaba pa. Foram coletados dos prontuários dos pacientes os resultados do julgamento da ocorrência (presença/ausência) do EAN durante a repetição de palavras com p e da emissão da palavra papai do TEAN, nas condições sem e com prótese de palato. Resultados: A medida da área velofaríngea e o julgamento da ocorrência do EAN mostraram-se significativamente menores na condição CP. Entretanto, a prótese conseguiu eliminar o EAN em 63,9% dos pacientes, quando se toma a emissão de palavras com a consoante p na avaliação articulatória para comparação, e eliminá-lo em 50% deles quando se toma a emissão da palavra papai do TEAN. Com a prótese, 56,4% pacientes apresentaram função velofaríngea adequada e 43,6% função velofaríngea diferente da adequada (adequada-marginal = 5,3%, marginal-inadequada = 5,3%, inadequada = 33%). Conclusões: As medidas da área velofaríngea obtidas por meio da técnica fluxopressão diminuem significativamente quando o paciente faz uso da prótese (condição com prótese), revelando que a prótese pode melhorar a função velofaríngea para a fala; embora a ocorrência do escape de ar nasal (EAN) na produção da consoante p demonstre ser menor com a prótese, tanto no julgamento pela modalidade auditiva quanto pela visual, a modalidade visual parece ser mais sensível para identificar a ocorrência do escape;o EAN demonstrou ter relação direta com a função velofaríngea, uma vez que apresentou-se ausente em uma função velofaríngea adequada (condição com prótese) e presente em uma função velofaríngea inadequada (condição sem prótese). Contudo, esta relação pode estar susceptível à interferência de muitos fatores que podem influenciar positivamente ou negativamente a ocorrência do EAN na função velofaríngea. / Introduction: Although perceptual judgement is recognized to be the gold standard for clinical speech evaluation of cleft palate and/or velopharyngeal dysfunction (VPD) patients, it can be influenced by a number of factors due to its subjectivity. Instrumental assessment such as pressure-flow technique can provide additional information related to speech and velopharyngeal dysfunction findings in individuals adapted to palatal speech device with obturator pharyngeal bulb for treatment of VPD Objectives: Describe and compare the results of velopharyngeal area measurements by using pressure-flow technique and the judgment of the occurrence of air nasal emission (NAE) during repetition of words containing the p consonant and utterance of the word papai in the Test of Nasal Air Emission (TNAE), in conditions with and without palatal speech device as well as to analyze the relation between NAE and velopharyngeal dysfunction ratings in conditions with and without palatal speech device.Method: A retrospective study of samples including 94 patients with diagnosis of velopharyngeal insufficiency wearing palatal prostheses with pharyngeal bulb was performed. Velopharyngeal function was rated (adequate, marginal-adequate, marginal-inadequate and inadequate) in according to velopharyngeal measurements obtained from aerodynamic evaluation during the production of p consonant in the segment pa. The results of NAE occurrence judgement (present/absent) during the repetition of words with p and utterance of papai in the TNAE were collected from the patients´s recordings, in the conditions with and without prosthesis. Results: Velopharyngeal area measurements and NAE occurrence judgement were significantly lower in the with-prosthesis condition. However, speech prosthesis was able to eliminate NAE in 63.9% of the patients, when considering utterances of words with p in articulatory evaluation as comparison, and managed to eliminate it by 50% of them with regard to the word papai in the TEAN. With the speech device, 56.4% of patients demonstrated adequate velopharyngeal function and 43.6% showed velopharyngeal ratings different of the adequate one (marginal adequate = 5.3%, marginal inadequate = 5.3% and inadequate = 33%).Conclusions: The measures of velopharyngeal area obtained byusing pressure-flow technique decreased significantly when the patient uses prosthesis (condition with prosthesis), revealing that the prosthetic device can improve velopharyngeal function for the speech. Although the occurrence of nasal air flow (EAN) in the production of the consonant p presents to be lower with prosthesis, either in the hearing judgement as in the visual one, the latter seems to be more sensible to identify the occurrence of flow. Nasal air flow (EAN) demonstrated to have a direct relation with the velopharyngeal function for it was absent in an adequate velopharyngeal function (condition with prosthesis) and present in an inadequate velopharyngeal function (condition without prosthesis). Nevertheless, this relation may be susceptible to the interference of many factors that may positively or negatively influence the occurrence of EAN in the velopharyngeal function.

Neste trabalho propôs-se a construção de um tubo de material compósito híbrido, com fibra de vidro e fibra de carbono, para utilização como prolongador de prótese de membro inferior a serem fabricadas pela AACD - Associação de Assistência à Criança Deficiente. O objetivo é avaliar as solicitações da prótese para otimizar custo e reduzir a massa. Fez-se inicialmente um levantamento das propriedades dos materiais comerciais utilizados para a fabricação do prolongador para referenciar o desenvolvimento do componente da prótese. Utilizou-se modelagem por elementos finitos para otimizar o componente em função dos esforços biomecânicos a que a prótese é submetida. Nesta modelagem, estudaram-se várias disposições, quantidade e material das camadas de forma a atender às solicitações e minimizar os custos. O levantamento bibliográfico permitiu encontrar uma rota de menor custo para a fabricação de compósito que utiliza um processo de transferência de resina auxiliado a vácuo e pré-formados de vidro e carbono. Como referência, foi fabricado um componente pelo processo de bobinagem filamentar que produz materiais compósitos de qualidade reconhecida. O processo de moldagem por transferência de resina assistido à vácuo, apesar de ter alguns insumos importados, pela sua simplicidade pode ser realizado na própria AACD e se mostrou capaz de obter componentes com custo que viabiliza sua produção sem grandes investimentos em equipamentos. Apesar da redução de algumas das propriedades em relação à peça de referência, o tubo apresentou vantagens na redução de massa e na absorção de impacto. / In this work it was considered a construction of a pipe of hybrid composite material, with carbon and glass fibre, for use as prosthesis extension of inferior member to be manufactured for the Associação de Assistência à Criança Deficiente AACD. The objective is to evaluate the requests of prosthesis to optimize cost and to reduce weight. A survey of the properties of the commercial materials commonly used for the manufacture extension became initially a reference to the development of the final component. A finite element modeling was used to optimize the component in the biomechanics function related to the efforts which the prosthesis is submitted. In this modeling some disposals and numbers of layers, amount and material have been studied to take care of the requests and to minimize the cost. A bibliographical survey allowed finding a shipper route for the manufacture of composite that uses a process of vacuum assisted resin transfer molding and preforms of glass with carbon. As reference, a component was produced using filament winding process to compare the quality of the obtained composite pipe. The process, although to have some imported feed-stock, can be proper carried out by AACD and if it showed capable to produce components with cost that makes possible its production internally. Despite the reduction of some of the properties in relation to the reference part, the component presented advantages such as weight reduction and the impact absorption.

Objetivo: Considerando que a precisão na adaptação do implante ao intermediário transmucoso é fator importante para a longevidade da prótese e que os sistemas de implantes possuem origens diversas na sua fabricação, nos propusemos a verificar a infiltração da bactéria Enterococcus faecalis na interface entre intermediário transmucoso e implantes do tipo Cone Morse e Hexágono Interno no sistema Neodent . Material e Método: A amostra foi composta por 20 implantes do tipo Cone Morse com Index Protético, 20 implantes Titamax Cone Morse e 20 implantes de Hexágono Interno e 20 intermediários transmucosos do tipo Munhão Universal CM Exact, 20 Munhão Universal em corpo único de 3,3 x 5,5 mm e 20 Munhão Universal II Plus com Parafuso. Com o auxílio da Micropipeta o Inóculo foi aspirado, imediatamente após, inserido no interior do implante que se encontrava estático na placa do Dispositivo desenvolvido para este experimento. Os intermediários foram então conectados e apertados com chave digital própria, em seguida, foi dado o torque ao parafuso do intermediário de acordo com as recomendações do fabricante. Após o torque o conjunto, implante-intermediário foi removido da placa do Dispositivo com pinça de titânio e inserido dentro do tubo de ensaio que continha o meio de cultura estéril. Diante do conhecimento da área interna de cada implante, o volume do Inóculo a ser utilizado foi determinado em 1L. Todos os tubos contendo os conjuntos foram numerados e incubados a 37oC por um período de 14 dias. Foi realizado acompanhamento diário para verificação da possível passagem de bactérias do interior do implante para o caldo. O indicativo da passagem de bactéria para o meio foi a turvação do meio de cultura (caldo BHI). Decorrido os 14 dias de observação, os dados foram tabulados e submetidos à Análise de Variância (ANOVA) com nível de significância de 5%, quando detectada diferença estatística, os valores foram submetidos ao Teste de Tuckey para comparações múltiplas. Resultados: O Teste de Tukey evidenciou que houve diferença estatisticamente significante entre o grupo de implantes Cone Morse, Cone Morse Índex e Hexágono Interno, onde o grupo de implantes Cone Morse diferiu estatisticamente do grupo Cone Morse Índex e também do grupo de implantes de Hexágono Interno. O grupo de implantes Cone Morse Índex não diferiu estatisticamente do grupo de implantes de Hexágono Interno, porém o grupo Cone Morse Índex presentou os melhores resultados. / Objective: Whereas the accuracy adaptation of the implant abutment is an important factor for the longevity of the prosthesis, and implant systems have diverse backgrounds in its manufacture, we set out to verify the infiltration of Enterococcus faecalis bacteria at the interface between the abutment and transmucosal implants of Morse Taper and Internal Hex of Neodent system. Material and Methods: The sample consisted of 20 Morse Taper implants, 20 Titamax Morse Taper implants, 20 Internal Hexagon implants and 20 transmucosal Exact CM Universal Post abutment, 20 Universal Post 3 in one body , 3 x 5.5mm and 20 Universal Post II Plus with Screw . With the aid of a micropipette the inoculum was aspirated, immediately thereafter, inserted into the implant that was in the static device board developed for this experiment. The abutments were then connected and tightened to own digital key, then the torque was given to the screw of the abutment according to the manufacturer\'s recommendations. After the torque, deploy abutment was removed from the plate clamp device of titanium and inserted into a test tube containing sterile culture. According to the internal area of each implant, the inoculum size was determined to be 1L. All the tubes were numbered and incubated at 37 ° C for a period of 14 days. Daily monitoring to check the possible passage of bacteria into the interior of the implant broth was carried out. The indication of the passage of bacteria was turbidity of the culture (BHI). Upon expiry of the 14 days of observation, the data were tabulated and an analysis of variance (ANOVA) with a significance level of 5 % was done. The values were submitted to Tukey test for multiple comparisons. Results: The Tukey test showed a statistically significant difference between the group of Morse Taper implants, Cone Morse Index and Internal Hex, where the group of implants differed from Morse Taper, Morse Taper Index group and also the group of Internal Hexagon implants. The group of Morse Taper implants Index did not differ statistically from the group of Internal hexagon implants, but Morse Taper Index group showed the best results

Les céramiques bioinertes (zircone, alumine), sont utilisées dans des dispositifs médicaux pour l’orthopédie et l’odontologie. Leurs surfaces peuvent avoir plusieurs fonctions : fixation du dispositif dans le milieu vivant (ex : implants dentaires), rôle tribologique (prothèses articulaires)… Dans tous les cas, ces surfaces sont traitées pour maximiser leur performance, mais ces modifications peuvent entrainer des conséquences négatives. Ainsi, le 2e chapitre montre qu’introduire de la rugosité par sablage joue sur l’intégrité mécanique et sur la stabilité à long terme de l’alumine, de la zircone et d’un composite alumine-zircone. Par ailleurs, dans les prothèses articulaires, la lubrification joue un rôle fondamental pour minimiser l’usure et donc augmenter la durée de vie moyenne des implants, permettant en outre de favoriser l’adsorption de protéines réduisant le contact direct entre les deux surfaces glissantes. La chimie des surfaces (y compris la présence de contamination) peut modifier ces aspects. Dans le 3e chapitre de ma thèse j’ai étudié l’effet de la contamination et des différentes techniques de nettoyage permettant de la réduire sur la mouillabilité des matériaux typiquement utilisés dans les prothèses de hanche, et sur l’adsorption de protéines à leurs surfaces. Finalement, les cellules utilisent les protéines en surface comme points de fixation et identification. Les implants avec une surface capable de recruter plus de protéines aidant à l’adhésion des cellules auront plus des chances d’être intégrés que des implants recrutant des protéines qui empêchent l’adhésion. Dans le 4e chapitre, j’ai exploré un nouveau concept de modification de surface de la zircone consistant en un greffage d’organosilanes directement sur sa surface, de manière à prouver le potentiel de cette technique à améliorer l’ostéointegration sans diminuer la performance mécanique. / Bioinert ceramics (zirconia, alumina) are used in medical devices in orthopedics and dentistry. Their surfaces may provide different functions: fixation of the device in the living tissue (e.g. dental implants), tribological role(joint substitutions),… In all cases the surfaces are treated to maximize their performance, but this modifications may entail negative consequences. The use of roughness to promote osseointegration of implants is a common practice, especially on dental implants. Roughening is often conducted by mechanical treatments, the most common being sandblasting. Therefore, chapter 2 focus on the implications of roughening by sandblasting on the mechanical behaviour of zirconia, alumina and a zirconia-alumina composite, and the differences between them. The work brought in chapter 3 was carried out entirely during a six-month secondment at CeramTec GmbH. In a bearing couple, lubrication mechanisms are complex and wettability and proteins play a yet-to understand role. The study compared the wettability of different materials, their ability to welcome protein adsorption and the effect of different cleaning procedures on wettability measurements and protein adsorption. Finally, the influence of the surface on cell activity is not driven exclusively by roughness: chemical modifications of the surface may enhance the perception of cells for the surface, and by careful tuning of the surface properties one may achieve a better integration without the downsides of roughness. In chapter 4, we explored a novel modification of zirconia, based on known techniques in chemistry, which introduces molecules with special functional groups capable of rendering the surface friendlier for cell adhesion, and opening the window for new exciting developments in the field of bioinert ceramics.

Electrical stimulation of the retina affected by photoreceptor loss (e.g., cases of retinitis pigmentosa) elicits the perception of luminous spots (so-called phosphenes) in the visual field. This phenomenon, attributed to the relatively high survival rates of neurons comprising the retina's inner layer, serves as the cornerstone of efforts to provide a microelectronic retinal prosthesis -- a device analogous to the cochlear implant. This thesis concerns phosphenes -- their elicitation and modulation, and, in turn, image analysis for use in a prosthesis. This thesis begins with a comparative review of visual modelling of electrical epiretinal stimulation and analogous acoustic modelling of electrical cochlear stimulation. The latter models involve coloured noise played to normal listeners so as to investigate speech processing and electrode design for use in cochlear implants. Subsequently, four experiments (three psychophysical and one numerical), and two statistical analyses, are presented. Intrinsic signal optical imaging in cerebral cortex is canvassed appendically. The first experiment describes a visual tracking task administered to 20 normal observers afforded simulated prosthetic vision. Fixation, saccade, and smooth pursuit, and the effect of practice, were assessed. Further, an image analysis scheme is demonstrated that, compared to existing approaches, assisted fixation and pursuit (but not saccade) accuracy (35.8% and 6.8%, respectively), and required less phosphene array scanning. Subsequently, (numerical) information-theoretic reasoning is provided for the scheme's superiority. This reasoning was then employed to further optimise the scheme (resulting in a filter comprising overlapping Gaussian kernels), and may be readily extended to arbitrary arrangements of many phosphenes. A face recognition study, wherein stimuli comprised either size- or intensity-modulated phosphenes, is then presented. The study involved unpracticed observers (n=85), and showed no 'size' --versus--'intensity' effect. Overall, a 400-phosphene (100-phosphene) image afforded subjects 89.0% (64.0%) correct recognition (two-interval forced-choice paradigm) when five seconds' scanning was allowed. Performance fell (64.5%) when the 400-phosphene image was stabilised on the retina and presented briefly. Scanning was similar in 400- and 100-phosphene tasks. The final chapter presents the statistical effects of sampling and rendering jitter on the phosphene image. These results may generalise to low-resolution imaging systems involving loosely packed pixels.

Eight out of ten people in the United States will have problems with low back pain at some point in their life. The most significant surgical treatments for low back pain can be distributed into two main groups of solutions: arthrodesis and arthroplasty. Spinal arthrodesis consists of the fusion of a degenerated functional spine unit (FSU) to alleviate pain and prevent mechanical instability. Spinal arthroplasty consists of the implantation of an artificial disc to restore the functionality of the degenerated FSU. The objective of this study is to analyze and compare the alteration of the biomechanics of the lumbar spine treated either by arthrodesis or arthroplasty. A three-dimensional finite element model of a ligamentous lumbar motion segment, constituted of two FSUs, was built and simulated through a static analysis with the finite element software ABAQUS. It was shown that the mobility of the segment treated by arthrodesis was reduced in all rotational degrees of freedom by an average of approximately 44%, relative to the healthy model. Conversely, the mobility of the segment treated by arthroplasty was increased in all rotational degrees of freedom by an average of approximately 52%. The FSU implanted with the artificial disc showed a high risk of instability and further degeneration. The mobility and the stresses in the healthy FSU, adjacent to the restored FSU in the segment treated by arthroplasty, were also increased. In conclusion, the simulation of the arthroplasty model showed more risks of instability and further degeneration, on the treated level as well as on the adjacent levels, than in the arthrodesis model.

Atherosclerosis is an inflammatory disease which develops focally in regions of the vasculature where there is dysfunction of endothelial cells modulated in part by shear stress from flowing blood. To address the clinical crisis of atherosclerosis, tissue engineering has focused on development of a living blood vessel substitute for use as a vascular graft in bypass surgery. Despite substantial progress in understanding the biological basis and developing clinical treatments for cardiovascular disease, critical challenges remain. As a novel strategy to improve understanding of basic human vascular biology and develop superior tissue engineered grafts, this dissertation combines the scientific and clinical approaches by using a tissue engineered blood vessel as a more physiologic in vitro model to study endothelial cell biology. Through the use of transcriptional profiling, results demonstrate significant changes in endothelial cell gene expression using the tissue engineered blood vessel model. Furthermore, the presence of a more physiologic substrate alters the cellular response to shear stress which is a critical mediator of vascular pathology. A case study of endothelial cell function in this system focuses on cell-cell communication through gap junctions. Endothelial cell connexins which form gap junctions are shown to be differentially regulated by substrate and shear stress. Moreover, gap junction communication between endothelial cells is modulated by the mechanical environment. Studies using RNA interference to knockdown expression of individual connexin isotypes demonstrate integrated regulation of connexins yet unique roles in endothelial cell function. Collectively, results exemplify the sensitivity of endothelial cell phenotype to substrate and shear stress and underline the importance of using more physiologic models in the study of basic cell biology.