Submitted by Rodrigo Diniz do Prado null (rodrigodiniz.prado@hotmail.com) on 2017-02-09T13:48:10Z No. of bitstreams: 1 Dissert.Mestrado.Rodrigo.Diniz.pdf: 2142391 bytes, checksum: 98314a8816d0ae481af3108941d7a2c2 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-14T15:59:08Z (GMT) No. of bitstreams: 1 prado_rd_me_sjc.pdf: 2142391 bytes, checksum: 98314a8816d0ae481af3108941d7a2c2 (MD5) / Made available in DSpace on 2017-02-14T15:59:08Z (GMT). No. of bitstreams: 1 prado_rd_me_sjc.pdf: 2142391 bytes, checksum: 98314a8816d0ae481af3108941d7a2c2 (MD5) Previous issue date: 2016-12-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste estudo foi avaliar o efeito do desgaste com broca diamantada, o envelhecimento (degradação em baixa temperatura) e espessura do material cerâmico no comportamento mecânico de uma cerâmica Y-TZP. Para este estudo, 240 espécimes foram fabricados em formato de disco, de acordo com a norma ISO 6872: 2008 para resistência à flexão biaxial de amostras de cerâmica (N = 120, com dimensões de 0,5 mm de espessura x 15 mm de diâmetro; N = 120 com a dimensão 1,0 milímetros de espessura x diâmetro 15 mm). Os espécimes foram divididos aleatoriamente em 8 grupos (n = 30), de acordo com três fatores em estudo: 'desgaste' em 2 níveis (com e sem desgaste com broca diamantada), o envelhecimento em 2 níveis (com e sem envelhecimento) e da espessura da cerâmica também em 2 níveis (0,5 a 1,0 mm). O desgaste foi realizado com uma broca diamantada montada em um motor de baixa rotação associado a um contra-ângulo multiplicador de velocidade (T2 REVOR R170, Sirona, Bensheim, Alemanha), sob constante irrigação de água. O envelhecimento foi simulado em uma autoclave à temperatura de 134 °C, durante um período de 20 horas, sob pressão de 2 bar. Após o desgaste e envelhecimento, análises de rugosidade e topográficas foram realizadas e análises de transformação de fase por difração de raios-X. Os dados coletados foram submetidos à análise de Weibull. O desgaste promoveu um aumento da rugosidade, enquanto que o envelhecimento em autoclave não afetou estatisticamente a rugosidade da superfície. Além disso, tanto o desgaste quanto o envelhecimento aumentaram a quantidade fase monoclínica, embora, o desgaste levou a uma diminuição da susceptibilidade do material a uma nova transformação de fase durante o envelhecimento (resultando em maior percentual de fase m para a condição controle após envelhecimento em comparação a condição desgaste após envelhecimento). Independente da espessura de zircônia, o envelhecimento em autoclave e o desgaste levaram a um aumento da resistência característica. Dentro dos limites do presente estudo, observou-se que o desgaste e o envelhecimento não promovem efeitos deletério no comportamento mecânico da cerâmica Y-TZP, para ambas espessuras (0,5 mm e 1,0 mm). / The goals of this investigation were to evaluate the effects of grinding with diamond bur and aging (low temperature degradation) on the mechanical behavior of a full-contour Y-TZP ceramic with two thicknesses. Y-TZP shaped-disc specimens (Zirlux FC, Ardent Dental) were manufactured with thickness of 0.5 mm and 1.0 mm (both with 15 mm in diameter). The specimens from every thickness were randomly assigned into 4 groups, according to two factors: ‘grinding’ on 2 levels (with and without grinding with diamond bur), aging in 2 levels (with and without aging). Grinding was performed with a diamond bur mounted in a slow speed rotation motor associated with a counter-angle speed multiplier hand-piece, under constant water-cooling. Low temperature aging was performed in an autoclave at 134°C temperature, for a period of 20h, under 2 bar of pressure. After grinding and aging, roughness analyzes were performed on a surface roughness tester and 3D digital optical profilometer; topographic analysis were made in a scanning electron microscope; phase transformation analysis by X-ray diffraction. Biaxial flexural strength tests were performed in the universal testing machine. Specific statistical analyses were carried out (Weibull analysis for the strength data). Grinding promoted an increase in roughness, while aging in autoclave did not affect statistically the surface roughness. Also, grinding and aging lead to higher values of m-phase content, although, grinding lead to a decrease in the material susceptibility to a new phase transformations during aging (after aging, as-sintered condition resulted in higher m-phase content compared with ground). Independent on the zirconia’s thickness, aging in autoclave and grinding led to an increase in characteristic strengths. Within the limits of this study, it was observed that: grinding and low temperature aging in autoclave do not damage the mechanical behavior of the tested Y-TZP ceramic, for both thicknesses (0.5 mm and 1 mm). Despite those conditions led to high m-phase content, a thinner thickness of 0.5 mm presented similar or higher characteristic strength compared with the 1.0 mm thickness both before and after grinding and aging.

Orientador: João Roberto Gonçalves / Banca: Ary dos Santos-Pinto / Banca: Roberto Henrique Barbeiro / Banca: Darceny Zanetta Barbosa / Banca: Terumi Okada / Resumo: Este estudo avaliou a resposta do tecido mole, do espaço faríngeo e a estabilidade após avanço maxilo-mandibular com rotação anti-horária e reconstrução da ATM com próteses totais articulares do tipo TMJ Concepts system®. As mudanças cirúrgicas e pós-cirúrgicas foram analisadas utilizando-se telerradiografias laterais. Com o movimento cirúrgico, houve redução do ângulo do plano oclusal (14,9 ± 8,0°) e aumento do espaço aéreo faríngeo - PASnar (4,9mm). A região anterior da maxila moveu-se para a frente e para cima enquanto a porção posterior, para a frente e para baixo. A mandíbula avançou, e sofreu rotação no sentido anti-horário. No período pós-cirúrgico, a maxila apresentou alterações mínimas no plano horizontal, enquanto todas as medidas mandibulares permaneceram estáveis. A postura da cabeça (OPT/NS) mostrou flexão imediatamente após a cirurgia e extensão em longo prazo, enquanto a curvatura cervical (OPT/CVT) não apresentou mudanças. Os resultados cirúrgicos mostraram ainda aumento das distâncias entre a terceira vértebra cervical (C3) e o mento e desta com o hióide, permanecendo estáveis durante o período de observação. A distância entre o osso hióide e o plano mandibular reduziu durante e após a cirurgia. Já a resposta do tecido mole evidenciou diferentes razões entre tecido duro/mole nos pacientes com e sem genioplastia. As mudanças horizontais na morfologia do lábio superior após avanço, impacção da maxila, sutura em VY e sutura da base alar mostraram maior movimento do que as mudanças observadas em tecido duro. O avanço maxilo-mandibular com rotação anti-horária do plano oclusal associado a próteses totais de ATM (TMJ Concepts system®) mostrou-se estável durante o período de observação. O espaço aéreo faríngeo aumentou... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study evaluated stability, soft tissue response and oropharyngeal airway space changes after maxillo-mandibular advancement and counter-clockwise rotation with TMJ reconstruction using TMJ Concepts system® total joint prostheses. Lateral cephalograms were analyzed to estimate surgical and post surgical changes. During surgery, the occlusal plane angle decreased 14.9 ± 8.0° and the retroglossal airway space (PASnar) increased 4.9mm. The anterior region of maxilla moved forward and upward while the posterior nasal spine moved downward and forward. The mandible changed forward and rotated in a counter-clockwise direction. At long-term follow-up evaluation the maxilla showed minor horizontal changes, while all mandibular measurements remained stable. Head posture (OPT/NS) showed flexure immediately after surgery and extension long-term post surgery, while cervical curvature (OPT/CVT) had no significant changes. Surgery increased the distances between the third cervical vertebrae (C3) and menton, and C3 and hyoid, remaining stable afterwards. The distance from the hyoid to the mandibular plane decreased during surgery and in the longest follow-up. Soft tissue response indicated different hard/soft tissue ratios between patients with or without genioplasties. Horizontal changes in upper lip morphology after maxillary advancement/impaction, VY closure, and alar base cinch sutures showed greater movement, than observed in hard tissue. TMJ Concepts total joint prostheses associated with maxillo-mandibular advancement and counter-clockwise rotation showed to be stable during the follow-up observation period. Immediate increase in oropharyngeal airway dimension, was influenced by post-surgical changes in head posture but remained stable over the follow-up period. Soft tissue changes showed a known predictable response. / Doutor

Resumo: O câncer da região de cabeça e pescoço é uma doença muito prevalente no Brasil, e as principais formas de tratamento são a cirurgia acompanhada ou não da radioterapia e quimioterapia. Perdas parciais ou totais de osso maxilar podem comprometer seriamente a fisiologia bucal causando sequelas como comunicações buconasosinosal. Neste caso, podese optar como forma de tratamento pela reabilitação protética com a aplicação de implantes osseointegrados. A literatura odontológica tem mostrado inúmeros trabalhos que avaliam a distribuição de forças com a finalidade de recolher melhores subsídios para o planejamento de próteses bucomaxilofaciais, que ainda é pouquíssimo explorada. Dentre os métodos utilizados, o da fotoelasticidade tem sido aceito, especialmente por permitir uma análise fiel da distribuição de forças. Assim, a proposta deste trabalho foi verificar a tendência de distribuição de forças e estresse, através do método fotoelástico, que incidem sobre diferentes tipos de sistemas de retenção em implantes (o'ring, barra clipe e o'ring/barra clipe) associado a próteses obturadoras palatinas implantoretidas e também em próteses obturadoras mucossuportadas (sem implante), utilizandose ou não de silicone com reembasamento direto (Sofreliner). O conjunto (prótese e modelo fotoelástico) foi posicionado em polariscópio circular e recebeu aplicação de carga de 100 N a velocidade de 10 mm/s no primeiro molar de cada prótese. Após as aplicações de carga houve a formação franjas correspondentes à tensão registrada. Então, as imagens foram transferidas para um computador e analisadas no programa ADOBE Photoshop. Ao se comparar os três sistemas de retenção das próteses obturadoras palatinas implantoretidas com a prótese mucossuportada (sem implantes), podese observar que as tensões foram distribuídas de forma mais homogênea... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The head and neck cancer is a very prevalent disease in Brazil and the main treatment is the surgery with or without radiation therapy and chemotherapy. Partial or total bone maxillary defects could involve seriously oral physiology causing consequences as buconasosinosal communications. In this case could be applied other option of treatment as prosthetic rehabilitation associated with osseointegrated implants. Scientific literature demonstrated countless studies that evaluate the force distribution with the aim to provide better subsidies for the planning of bucomaxillofacial prostheses, which still have few researches. Between the methodologies, the photoelastic method has been accepted; especially by allow an accurate analysis of the force distribution. Thus, the aim of this study was to verify the tendency of force distribution and the stress on different types of retention system (o'ring, clip bar and o'ring/clip bar) associated with palatal obturator prostheses with implant retention and conventional obturator prostheses (without implants), with or without silicone soft lining(Sofreliner), by means of photoelastic method. The set (prosthesis and photoelastic model) was located in circular polariscope and was applied a load of 100 load N at 10 mm/s on the first molar of each prostheses. After the load applications was registered the tension fringes. The images was transferred to a computer and analyzed at ADOBE Photoshop software. When compared the three retention systems of the palatal obturator prostheses and mucosupported prostheses (without implants), it can be observed that the stress was distributed more homogeneous and in lesser amount that the conventional prostheses, when compared to the other prostheses that presented implants and retention systems. With relation to stress distribution in the different retention systems, the bar clip... (Complete abstract click electronic access below) / Orientador: Marcelo Coelho Goiato / Coorientador: Stefan Fiúza de Carvalho Dekon / Banca: Eduardo Piza Pellizzer / Banca: Mauro Antônio de Arruda Nóbilo / Mestre

Orientador: Eduardo Piza Pellizzer / Coorientador: Fellippo Ramos Verri / Banca: Joel Ferreira Santiago Junior / Banca: Aimée Maria Guiotti / Resumo: Este projeto teve como objetivo analisar as tensões geradas por próteses fixas unitárias e esplintadas sobre implantes cone morse, em maxilar posterior, variando o comprimento dos implantes e fixação protética, por meio do método dos elementos finitos tridimensionais não linear. Foram simulados 12 modelos tridimensionais com ajuda dos programas de desenho assistido Rhinoceros 3D 4.0 (NURBS Modeling for Windows, USA) e SolidWorks 2011 (SolidWorks Corp, USA), além do programa InVesalius (CTI, São Paulo, Brasil), utilizado para confecção da porção óssea. Cada modelo representou uma seção de osso da região posterior maxilar, na forma de um bloco de osso tipo III (cortical e esponjoso), com a presença de 3 implantes do tipo cone morse, com 4,0mm de diâmetro e com diferentes comprimentos, colocados 1mm infra-ósseo, suportando prótese de 3 elementos, com coroas metalocerâmicas. No capítulo 1 foram considerados modelos variando os sistemas de retenção (Parafusadas x cimentadas), e o fator esplintagem (próteses unitárias x próteses esplintadas), enquanto que no capítulo 2 foram considerados apenas próteses unitárias variando os sistemas de retenção (Parafadas x cimentadas) e o comprimento dos implantes (7,0mm, 8,5mm, 10mm e 11,5mm). Os desenhos tridimensionais foram exportados ao programa de pré e pós processamento FEMAP v.11.0 (Siemens Product Lifecycle Management Software Inc. USA) para geração da malha, restrições e aplicação de uma carga de 400N axial e 200N oblíqua (45°), nas vertentes internas da coroa. A análise foi realizada no programa de elementos finitos NEiNastran 11 (Noran Engineering, Inc., EUA) e os resultados foram visualizados através de mapas de tensão von Mises e Tensão Máxima Principal individualizados em cada modelo proposto no programa FEMAP... / Abstract: This project aimed to evaluate the stress on single and splinted implant-supported fixed prostheses over morse taper implants in the posterior region of the maxilla, varying the length of the implants and prosthetic fixation, by three-dimensional nonlinear finite element method. Twelve three-dimensional models were simulated with Rhinoceros 3D 4.0 software (NURBS Modeling for Windows, USA) and SolidWorks 2011 software (SolidWorks Corp, USA). The bone portion was obtained by use of InVesalius software (CTI, São Paulo, Brasil). Each model presented a section of bone of the maxillary posterior region in the form of a type III bone block (cortical and trabecular), with the presence of three morse tapper type implants with 4,0mm in diameter and different lenghts (7,0mm, 8,5mm, 10mm, 11,5mm) placed 1mm below at cortical bone surface supporting prostheses of three elements with metal-ceramic crowns. In chapter 1 was considered models varying the fixation systems (screw-retained x cement-retained), and the splinting (single-unit prostheses x splinted prosthesis), while in Chapter 2 was considered only single-unit prostheses varying the fixation systems (screw-retained x cement-retained), and the length of the implants (7.0mm, 8.5mm, 10mm and 11.5mm). The three-dimensional models were exported to pre- and post- processing in the FEMAP v.11.0 software (Siemens Product Lifecycle Management Software Inc. USA) for mesh generation, restrictions and configuration of load of 400N axial and 200N oblique (45º) applied at each dental cusp. The analysis was performad by NEiNastran 11 software (Noran Engineering, Inc., EUA) and results were displayed using von Mises tension maps and Maximum Principal Stress tension maps that were individualized for each proposed model as necessary. The Chapter 1 results showed that... / Mestre

Estudou-se a fala de idosos submetidos a diferentes modalidades de reabilitação oral para verificar se o tipo de modalidade interferiu na produção da fala. Após aprovação do Comitê de Ética em Pesquisa, 36 idosos (média=68 anos) foram avaliados, formando-se 3 grupos: 13 com dentes naturais no mínimo até o 2º pré-molar (A) e outros dois grupos de desdentados reabilitados, sendo um com 13 usuários de prótese total mucosossuportada superior e inferior (B) e outro com 10 usuários de prótese total mucosossuportada superior e implantossuportada inferior (C). Excluíram-se casos com histórico de doenças neurológica, oncológica da região da cabeça e pescoço e psiquiátrica; realização de cirurgia laríngea; etilismo; usuários de medicamentos que causasse xerostomia; malformação craniofacial, má oclusão e disfunção velofaríngea; dificuldade auditiva ou usuário de Aparelho de Amplificação Sonora Individual e alteração cognitiva. A estabilidade das próteses foi avaliada por um cirurgião-dentista e amostras de fala foram registradas e analisadas por 5 fonoaudiólogos, orientados a: identificar articulação exagerada ou fechada, redução dos movimentos labiais e falta de controle salivar na fala espontânea; determinar a freqüência de alteração dos fones na análise da repetição de vocábulos e frases para o cálculo da Porcentagem de Consoantes Corretas (PCC); e a detectar troca de ponto articulatório, projeção lingual, ceceio, desvio mandibular ou distorção acústica na repetição de vocábulos e frases e na contagem de números. Análise acústica do fone [s] também foi realizada pela gravação digital das palavras-chave sapo, suco, siga, inseridas na frase-veículo: Digo ____ aqui, considerando-se os parâmetros: duração e freqüência do fone [s]. Segundo a opinião da maioria dos juízes observaram-se em todos os grupos poucos casos com alguma alteração de fala, com maior freqüência no grupo C, sendo a articulação travada verificada em todos os grupos, a redução dos movimentos labiais em dois grupos (A e B) e a articulação exagerada e a falta de controle salivar em um dos grupos (C e B). A concordância quanto à PCC entre os juízes foi verificada pela Estatística Kappa, observando-se variação entre concordância regular a quase perfeita. Verificou-se menor valor da PCC para os fonemas linguodentais nos grupos B e C, portanto com maior ocorrência de alteração, seguido dos fonemas alveolares. Houve predomínio de casos sem alteração no grupo A, contrariamente aos grupos B e C, nas duas amostras de fala estudadas, sendo a projeção lingual e o ceceio os tipos de alteração que mais ocorreram. A comparação entre os grupos não mostrou diferença. Quanto às próteses, a maioria do grupo B estava com a prótese inferior insatisfatória, não havendo associação entre alteração de fala e prótese insatisfatória. Em relação à análise acústica, a comparação dos valores da duração e da freqüência do fone [s] entre os grupos não mostrou diferença e, quando comparada à presença ou ausência de alteração na produção do [s] com a duração e a freqüência, também não se observou diferença. Apesar da amostra estudada ser pequena, pode-se concluir que o tipo de prótese, bem como a estabilidade desta parece não interferir na produção da fala. / In order to study the speech production of subjects submitted to different oral rehabilitation modalities, and to verify whether the modality type used would interfere in speech production, 36 elderly (average age = 68 years), both gender, were evaluated after the Research Ethics Committees approval. The sample was divided into 3 groups: group A, composed by 13 subjects with natural teeth, at least up to second premolar; group B, with 13 edentate subjects using maxillary and mandibular conventional denture; and group C, with 10 edentate subjects using maxillary conventional denture and mandibular implant-supported prosthesis. Exclusion criteria were medical history of neurological diseases, head and neck oncologic disease, psychiatric disease; laryngeal surgery; alcoholism; users of any drugs whose side effects could cause xerostomia; craniofacial malformation, malocclusion, and velopharyngeal dysfunction; hearing disorders or hearing aid users and cognitive alteration. A dentist evaluated the prosthesis stability. Recorded speech samples were obtained through spontaneous speech, vocable and sentences repetition, and counting of numbers. The analysis was executed by 5 speech pathologists. They were guided to perform a general impression of the spontaneous speech, identifying articulation, labial movements, and saliva control alterations. Besides that, they had to identify the frequency of phonemes alterations through the vocable and phrase repetition sample, and to detect the phonemes alterations types such as: articulation point changes, tongue projection, lisp or mandibular deviation, in the vocable and phrase repetition as well as in the counting of numbers. Analysis of the alterations frequency involved the calculation of Percentage of Correct Consonants (PCC), to verify the agreement among the observers, besides the comparison among groups, and between the association of alteration presence or absence, in the spontaneous speech, and the prosthesis stability. Acoustic analysis of the phoneme /s/ was also performed, throug h digital record of the speech. For that, a sentence-vehicle (Digo ____ aqui) reading or repetition was used, where Portuguese language key-words were inserted (sapo, suco, siga). Duration and frequency parameters of the phoneme /s/ were considered and compared among groups. Also, the alteration presence or absence in the /s/ production was compared to the duration and frequency of this phoneme. The results showed that, in spontaneous speech, there was a large speech alteration in group C. However, the alterations types were found in few occurrences, but in all of the studied groups. Speech alterations presence was identified in the vocable and phrase repetition as well as in the counting of numbers. A smaller Percentage of Correct Consonants value was observed for the linguodental phonemes, in groups B and C, therefore with a larger alteration occurrence, followed by the alveolar phonemes. There was a prevalence of occurrences without alterations in group A, contrarily to groups B and C, in the two speech samples studied, with the lisp and tongue projection being the most occurred alteration types. The comparison among groups, in relation to alteration frequency, showed no significant differences in the vocable and phrase repetition and counting of numbers. Dental evaluation showed that the majority of group B subjects had an unsatisfactory mandibular prosthesis, but an association could not be observed between speech alteration and unsatisfactory maxillary and mandibular prosthesis. There were no significant statistical differences in duration and frequency of the phoneme /s/ among groups. Comparison between alteration presence or absence in /s/ production and duration and frequency showed no significant statistical differences. In conclusion, despite the small sample, it appears that prosthesis type as well as stability does not interfere in speech production.

Universidade Federal do Cearà / A possÃvel presenÃa de microorganismos potencialmente patogÃnicos em prÃteses dentÃrias recÃm-chegadas dos laboratÃrios protÃticos deve ser considerada. Este estudo avaliou o nÃvel de contaminaÃÃo bacteriana e fÃngica de espÃcimes de resina acrÃlica confeccionados em 14 laboratÃrios de prÃtese dentÃria, inscritos no Conselho Regional de Odontologia do CearÃ, na cidade de Fortaleza. Cada laboratÃrio foi solicitado a confeccionar 10 espÃcimes de resina acrÃlica, a partir de modelos padronizados de silicona de adiÃÃo estÃreis, desconhecendo os objetivos da pesquisa. Os espÃcimes recebidos dos laboratÃrios foram colocados em tubos individuais contendo BHI caldo e incubados a 37ÂC por 48 horas e, em seguida, removidos, lavados, colocados em soluÃÃo salina estÃril e agitados para desprendimento microbiano. A suspensÃo obtida foi diluÃda em 1:100, 1:1000 e semeada em placas com Ãgar Sangue, Sabouraud Dextrose Ãgar e HICrome UTI ÃgarÂ, para incubaÃÃo por 48 horas a 37ÂC. Foi obtido o nÃmero de unidades formadoras de colÃnias (UFC) bacterianas e fÃngicas viÃveis, alÃm da identificaÃÃo e quantificaÃÃo de algumas espÃcies de bactÃrias, comparando-se os laboratÃrios por meio dos testes de Kruskall-Wallis e Dunn (&#945;=0.05). Houve contaminaÃÃo advinda de todos os laboratÃrios analizados, com uma contagem de UFC mÃdia de 101438 de bactÃrias e 71047 de fungos. Pseudomonas spp foi o microorganismo a mais prevalente identificado (p<0,05). Foi concluido que existe risco de contaminaÃÃo por bactÃrias potencialmente patogÃnicas e fungos em dispositivos protÃticos recÃm chegados dos laboratÃrios. / The possible presence of potentially pathogenic microorganisms in denture newly arrived from prosthetic laboratories should be considered. This study evaluated the level of bacterial and fungal contamination of specimens of acrylic resin made in 14 dental laboratories registered with the Regional Council of Dentistry of CearÃ, Fortaleza. Each laboratory was asked to fabricate 10 specimens of acrylic resin, from standard models of sterile silicone addition, unaware of the research objectives. Specimens received from laboratories were placed in individual tubes containing BHI broth, incubated at 37ÂC for 48 hours and then removed, washed and placed in sterile saline and stirred for microbial detachment. The suspension obtained was diluted (1:100, 1:1000) and plated on blood agar plates, and Sabouraud Dextrose Agar and Agar HiCrome ICU by incubation for 48 hours at 37ÂC. The number of colony forming units (CFU) bacterial and fungal viable was obtained, besides the identification and quantification of some species of bacteria, comparing the laboratory by means of the Kruskal-Wallis and Dunn (&#945; = 0.05) tests. There was contamination originating from all laboratories analyzed, with a mean CFU counts of 101438 bacteria and 71047 fungi. Pseudomonas spp was the most prevalent microorganism identified (p < 0.05). It was concluded that there is a risk of contamination with potentially pathogenic bacteria and fungi in prosthetic devices newly arrived from dental laboratories.

A utilização dos implantes cone morse muito favorece a estética peri-implantar e seu uso em conjunto com próteses cimentadas favorece ainda mais a estabilidade do sistema, simplificando também os procedimentos protéticos. O presente estudo histológico e histomorfométrico utilizou os implantes cone morse com o intuito de avaliar o comportamento tecidual com relação à posição da margem da cimentação protética em relação ao tecido ósseo quando se faz o uso próteses cimentadas. Foram utilizados quatro cães, os quais tiveram todos os pré-molares inferiores extraídos numa primeira fase cirúrgica. Após três meses, realizou-se a segunda fase cirúrgica, na qual foi realizada a técnica da carga imediata, com a instalação dos implantes juntamente com os pilares protéticos. Foram instalados vinte e quatro implantes numa profundidade de 3 mm infra óssea e eles foram igualmente divididos entre os grupos Controle e Experimental. Os pilares protéticos utilizados foram do tipo munhão universal e apresentavam diferentes alturas transmucosas iguais a 1.5 mm, 3.5 mm, e 5.5 mm. Isto fez com que a margem da cimentação se posicionasse a 1.5 mm infra óssea, a 0.5 mm supra óssea e a 2.5 mm supra óssea. No grupo Controle, foi realizada a instalação dos implantes e dos pilares protéticos somente. No grupo Experimental, foi realizada a instalação dos implantes, dos pilares protéticos e, sobre estes, foram cimentados cilindros de alumina. Os animais permaneceram sobre controle de placa durante 10 semanas subsequentes a instalação dos implantes, sendo este o tempo final do experimento através da realização da eutanásia. As amostras foram preparadas para análise histológica e avaliação dos tecidos peri-implantares. A região de interesse foi medida através da distância entre a margem do pilar protético e a porção mais coronal da crista óssea peri-implantar. Foram utilizados os testes estatísticos ANOVA a três critérios com medidas repetidas e teste de Tukey com o nível de significância de p < 0.05. Os resultados mostraram que não houve diferenças estatisticamente significantes entre os grupos Controle e Experimental (p = 0.2764) e que os pilares de 1.5 mm mostram menos perda óssea comparada aos outros pilares, considerando que a distância média da remodelação óssea foi menor neste grupo (0.6859 mm) comparada com os pilares de 3.5 mm (1.2917 mm) e 5.5 mm (1.0823 mm). Conclui-se que não há influência da profundidade da margem da cimentação protética no comportamento da crista óssea e que a utilização de diferentes alturas dos pilares protéticos não parece alterar o tecido ósseo marginal ao redor dos implantes Cone Morse. / The use of Morse taper implants has increased because of some positive features. Cemented crowns can be extensively used, taking advantage of the system connection stability, also simplifying the prosthetic procedures. The present histological and histomorphometric study used Morse taper implants with the purpose of evaluating bone behavior with respect to the cementation margin position of the prosthetic crown. Four dogs had all premolars extracted at a first surgical procedure. After three months, there was a second surgical procedure with simultaneous installation of implants and abutments, submitted to immediate load. Twenty four implants were installed 3 mm below the bone level and they were equally divided between Control and Experimental groups. The universal post abutments used had three different transmucosal heights, 1.5 mm, 3.5 mm and 5.5 mm. Thus there were implants with the level of the cementation margin positioned 1.5 mm below the bone level, as well as 0.5 mm and 2.5 mm above the bone level. In the Control group, installation of implants and abutments only was performed. In the Experimental group immediately after the placement of implants and abutments alumina cylinders were cemented. The animals were kept on plaque control for 10 weeks after implant placement and then euthanized. Samples were prepared for histological analysis and evaluation of peri-implant tissues. The region of interest was measured by the distance between the prosthetic margin of the abutment to the most coronal peri-implant bone crest. ANOVA test at three criteria with repeated measures and Tukey test with a significance level of p < 0.05 were applied. The results showed no statistically significant differences between Control and Experimental groups (p = 0.2764). The 1.5 mm abutments presented less bone loss compared to all other abutments tested, because the distance average of bone remodelation was shorter in this group (0.6859 mm) compared to the 3.5 mm abutment (1.2917 mm) and the 5.5 mm one (1.0823 mm). Conclusion: There is no influence of the depth of prosthetic marginal cementation on the behavior of bone crest and the use of different transmucosal heights of abutments does not seem to change the marginal bone surrounding morse taper implants.

OBJECTIVE: This study evaluated two embrasure designs by measuring their differential effect on load at failure of provisional fixed partial dentures (FPDs) fabricated of five commercially available polymer-based restorative materials. METHODS: Five provisional C&B materials were selected to fabricate FPDs with two different embrasure designs: sharp vs. rounded embrasures (n=12 for each material). The test materials included: Telio CAD (Ivoclar-Vivadent), Coldpac (Motloid), Protemp Plus (3M), VersaTemp (Sultan), and Turbo Temp (Danville). The embrasures were formed using prefabricated cutters with measured Radii (0.002r and 0.03r) and a fixture to hold each provisional FPD in place for the uniform standardized cuts. Molds for the CAD/CAM provisional FPDs were used to fabricate the syringeable temporary materials and form bridges with the same geometric design. All provisional bridges were cemented using Temp-Bond (Kerr) to the corresponding standardized abutments and tested to failure in a universal Instron testing machine by loading each specimen compressively in the mid pontic region. The load at break was recorded in Newton. A one-way analysis of variance (ANOVA) was used to compare the difference in each group’s mean. RESULTS: A significant difference in fracture load was found between the two groups of designs, in which the round embrasure was significantly stronger than was the sharp. A significant difference also was found between the type of temporary material used to fabricate the bridge in the two groups, and except for Coldpac, no significant difference between the embrasure anatomies was found. Fatigue loading did not appear to influence the two bridges’ fracture load, but it did show a significant difference with respect to the modulus of elasticity, in that the bridges that underwent fatigue loading showed a higher elastic modulus by comparison to the control group. Another variable that influenced the modulus of elasticity was the type of temporary material used to fabricate the bridge, in which TelioCAD was found to be the stiffest. However, the embrasure design did not seem to affect the bridges’ rigidity. CONCLUSION: A significant difference was found in fracture strength between the rounded and sharp embrasure design. Except for Coldpac, the rounded embrasure showed higher fracture toughness than did the sharp. No significant correlation was found between the two embrasure designs and the modulus of elasticity. Interestingly, the fatigued bridges that underwent cyclic loading showed a higher modulus of elasticity. The sharp embrasure design showed no fracture in the pontic region, while the rounded design did in 5.47% of the sample. This may be explained by the photoelastic bridges, in which the stress diffuses in the rounded design to include the pontic region, while in the sharp design, the stress is concentrated on the connector area. Stress analysis, both by means of photoelastic and finite element analysis, demonstrated that the bridge with the sharp embrasure design’s stress was high in the connector area compared to the round embrasure design.

>Magister Scientiae - MSc / Persons with lower limb amputations (LLA) experience different challenges in the community. These challenges include the physical, psychological and social function of an individual. Little is known in Malawi on what persons with lower limb amputations go through in the communities where they live. Therefore, the study aimed at exploring and determining community experiences of persons with LLA in Malawi. The study sought to address the following objectives: 1) To determine the functional and psychological status of persons with LLA in the community; 2) To explore and describe experiences on social participation of persons with LLA in the community; 3). To explore experiences on community re-integration following LLA. A mixed method approach was applied where quantitative and qualitative data were collected simultaneously to provide a more holistic overview of the experiences of persons with LLA at one point in time. The study setting was Queen Elizabeth Central Hospital (QECH) and Kamuzu Central Hospitals (KCH) (500 miles), located in Malawi. A sample of 180 participants was recruited to participate in the study. Three self-administered questionnaires (socio-demographic questionnaire, OPUS module of lower extremity functional status, and a Beck’s depression inventory scale) and a semi-structured interview guide were used for data collection. Thematic data analysis was used to analyze qualitative data, while quantitative data was analyzed using descriptive and inferential statistics. Ethical clearance was obtained from the University of the Western Cape Biomedical Research Ethics Committee (BMREC) and College of Medicine Research Ethics Committee (COMREC). Permission to conduct the study was obtained from KCH (500 miles) and QECH. Privacy andconfidentiality was strictly observed such that data obtained was anonymous. It was kept in a secure place, and electronic data was secured using a password.

A Tissue Engineering (TE) approach to heart valve replacement has the aim of producing an implant that is identical to healthy tissue in morphology, function and immune recognition. The aim is to harvest tissue from a patient, establish cells in culture from this tissue and then use these cells to grow a new tissue in a desired shape for the implant. The scaffold material that supports the growth of cells into a desired shape may be composed of a biodegradable polymer that degrades over time, so that the final engineered implant is composed entirely of living tissue. The approach used at Swinburne University was to induce the desired mechanical and functional properties of tissue and is to be developed in an environment subjected to flow stresses that mimicked the haemodynamic forces that natural tissue experiences. The full attainment of natural biomechanical and morphological properties of a TE structure has not as yet been demonstrated. In this thesis a review of Tissue Engineering of Heart Valves (TEHVs) is presented followed by an assessment of biocompatible materials currently used for TEHVs. The thrust of the work was the design and development of a Bioreactor (BR) system, capable of simulating the corresponding haemodynamic forces in vitro so that long-term cultivation of TEHVs and/or other structures can be mimicked. A full description of the developed BR and the verification of its functionality under various physiological conditions using Laser Doppler Anemometry (LDA) are given. An analysis of the fluid flow and shear stress forces in and around a heart valve scaffold is also provided. Finally, preliminary results related to a fabricated aortic TEHV-scaffold and the developed cell culture systems are presented and discussed. Attempts to establish viable cell lines from ovine cardiac tissue are also reported.