Thesis (M.S.)--Rochester Institute of Technology, 1984. / Typescript. Includes bibliographical references (leaves 38-39).

Thesis (Ph. D.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 137-151).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 107-108).

Orientador: Mauro Antonio de Arruda Nobilo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-06T16:55:24Z (GMT). No. of bitstreams: 1 Baboni_ClaudiaRahal_M.pdf: 1352784 bytes, checksum: a34de1b55cf421a9f8fc3a659dac35bc (MD5) Previous issue date: 2006 / Resumo: O presente estudo avaliou através de análise fotoelástica a passividade de infra-estrutura fundida em titânio, antes e após a aplicação de eletroerosão. Foi confeccionada uma matriz metálica simulando uma mandíbula humana onde foram implantados cinco análogos de pilares Micro-Unit (Conect ¿ AR, Conexão Sistemas de Prótese). A partir de um molde de silicone de duplicação foi confeccionado um modelo em resina fotoelástica com cinco implantes osseointegrados incorporados e pilares Micro-Unit. Sobre a matriz metálica foram realizados os procedimentos de enceramento de seis estruturas metálicas, inclusão, fundição em titânio comercialmente puro e acabamento das mesmas. Em todas as amostras foi realizada a soldagem a laser de cilindros de titânio e posterior avaliação em microscópio mensurador com precisão de 0,0005mm. A estrutura com melhor adaptação foi selecionada e submetida a análise fotoelástica conduzida pelo aperto dos parafusos em três seqüências preconizadas (1,2,3,4,5/ 5,4,3,2,1/ 3,2,4,1,5). A mesma estrutura foi submetida ao refinamento de adaptação pela técnica da eletroerosão (EDM) e subseqüente análise fotoelástica. Os resultados mostraram menor formação e intensidade das franjas fotoelásticas após o refinamento por eletroerosão em todas as seqüências de aperto dos parafusos. A seqüência (3,2,4,1,5), mostrou melhores resultados e a maior quantidade de tensões foram observadas ao redor dos implantes mediais em todas as seqüências em ambos os grupos. Pode-se concluir que o processo de eletroerosão melhora a adaptação marginal da infra-estrutura sendo eficaz para o alcance do assentamento passivo / Abstract: Through the photoelastic analysis, the present study evaluated the passive fit of titanium cast laser welding frameworks before and after the spark erosion procedure (Electrical Discharge Machining). A metallic matrix was made simulating a human mandible and, on top of it, 5 Micro-Unit abutment analogs had been implanted. A impression material mold was made and from it a photoelastic matrix had been created with 5 incorporated osseointegrated implants (Conect AR ¿ Conexão Sistemas de Prótese, São Paulo, Brazil) and with Micro-Unit abutment. Based on the metallic model, the following procedures were tested: closing 6 frameworks, embedding, casting in pure commercial titanium and finishing on them. A laser welding followed by an evaluation with microscope measurement with precision of 0.0005mm has been applied in all samples. The frameworks with best results had been selected and submitted to a photoelastic analysis followed by pressing the screws in 3 predisposed sequences (1,2,3,4,5/ 5,4,3,2,1/3,2,4,1,5). The same framework has been submitted to the adaptation refinement by spark erosion technique followed by the photoelastic analysis. The results demonstrated less photoelastics fringes in quantity and intensity after the spark erosion application in all screw pressing sequences. The sequence (3,2,4,1,5) achieved better results in both groups. A higher quantity of fringes had been observed around the medium implants in all sequences and in both groups. We can conclude that the titanium cast laser welded frameworks processes added to an spark erosion procedure improves significantly the marginal frameworks adaptation, which is effective for the passive fit of it / Mestrado / Protese Dental / Mestre em Clínica Odontológica

Orientador: José Ricardo de Albergaria Barbosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-20T21:59:25Z (GMT). No. of bitstreams: 1 Figueiredo_EvandroPortela_M.pdf: 2256697 bytes, checksum: bfe81580a0631a9ffe94d04bf2f85d23 (MD5) Previous issue date: 2012 / Resumo: O objetivo do presente estudo foi avaliar, comparativamente, in vitro, o efeito de diferentes sistemas de implantes, curtos e longos, sob carregamento axial e oblíquo, na distribuição de tensões em modelos fotoelásticos. Foi confeccionado 16 modelos fotoelásticos em resina (Resina Flexível GIII CMR-201 e endurecedor CME-252/ Polipox® Indústria e Comércio Ltda, São Paulo, SP, Brasil), com dimensões de 40 X 50 X 12mm, contendo implantes de sistemas e comprimentos diferentes. Os modelos foram distribuídos em quatro grupos: Grupo I (n=4) - Implante Neodent (longo) 5x11mm; Grupo II (n=4) - Implante Bicon (longo) 5x11mm; Grupo III (n=4) - Implante Neodent (Curto) 5x6mm; Grupo IV (n=4) - Implante Bicon (Curto) 5x6mm. Foram cimentadas aos conectores protéticos (3,5mm de altura), 4 coroas protéticas fabricadas com liga de cromo-cobalto. Para os implantes curtos a prótese apresentou as dimensões de 13mm de altura, 10mm no sentido mésio-distal e 8mm no sentido vestíbulo-lingual. As próteses para os implantes longos apresentaram as dimensões de 8mm de altura, 10mm no sentido mésio-distal e 8mm no sentido vestíbulo-lingual. Aplicou-se cargas axiais e oblíquas (15 graus) de 0,5 Kgf através de uma máquina de teste universal e um polariscópio circular foi utilizado para visualizar as tensões. Os resultados foram analisados, quantitativamente, através do programa Fringes®, em plataforma MATLAB do LPM/ FEMEC/UFU. Todos os implantes curtos apresentaram maiores níveis de tensão que os implantes longos, independente do sistema e da direção do carregamento. Os implantes curtos do sistema Neodent apresentaram maiores níveis de tensão na área cervical, quando comparados à mesma região dos implantes do sistema Bicon, sob carregamento oblíquo. O carregamento oblíquo resultou em maiores níveis de tensão nos implantes curtos do sistema Neodent que o carregamento axial. Dentro dos limites deste estudo conclui-se que implantes curtos estão sujeitos a maior tensão em consequência de cargas, quando comparados aos implantes longos / Abstract: The aim of this study was to compare, in vitro, the role of conventional and short implants of different implant systems, under axial and oblique loading, in stress distribution with photoelastic models. Sixteen models were fabricated with photoelastic resin (GIII Flexible Resin and hardener CMR-201-252 CME / Polipox ® Industria e Comercio Ltda, São Paulo, SP, Brazil), with dimensions 40x50x12 mm, containing different implants systems and different implant lengths. The models were divided into four groups: Group I (n=4) - conventional Neodent implant (5 x 11 mm); Group II (n=4) - conventional Bicon implant (5 x 11 mm); Group III (n=4) - short Neodent implant (5 x 6 mm); Group IV (n=4) - short Bicon implant (5 x 6 mm). Four prosthetic crowns made of cobalt chromium alloy were cimented on the abutments (3.5 mm in height). For the short implants the prosthesis dimensions were 13 mm in height, 10 mm mesiodistally and 8 mm buccolingually. The prosthesis for conventional implants had 8 mm in height, 10 mm mesiodistally and 8 mm buccolingually. Axial and oblique load (15 degrees) of 0.5 kgf was applied by a universal testing machine and a circular polariscope was used to visualize the stress. The results were analysed quantitatively by Fringes® program, in LPM/ FEMEC / UFU MATLAB platform. All short implants had higher stress levels than the conventional implants, regardless of the implant system and the load direction. The short Neodent implants system had higher levels of stress in the cervical third, compared to the same area of the Bicon implants system, under oblique loading. The oblique load resulted in higher levels of stress in the short Neodent implants system than the axial load. Thus, within the limits of this study, short implants are subjected to higher levels of stress as a result of loads when compared to conventional implants / Mestrado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Mestre em Clínica Odontológica

A technique has been developed, whereby the shock front produced in a shock tube can be used to apply a well-defined dynamic load for studies in dynamic photoelasticity. A brief review is given of the techniques that have been used, and the scope of research projects that have been undertaken in dynamic photoelasticity by other investigators. The theory related to shock front loading of models is presented. The work that has been carried out for this research project includes: The modification of an existing shock tube facility to accommodate a test section with parallel optical windows. The evaluation of the shock tube performance and the measurement of loading cycles imparted to models subjected to shock front impact. The design of a model housing to enable mounting a photoelastic model in the test section. The development of an optical system to enable photographing the dynamic fringe patterns produced in photoelastic models subject to shock front impact. A selection of photographs showing the dynamic fringe patterns produced in the models is included in this thesis and the dynamic stresses resulting from the loading method discussed. The results show that the technique could be extremely useful for studying dynamic stresses in models and some suggestions for future applications of the technique are given.

by Peng Haijing. / "June 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 115-124). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

published_or_final_version / Mechanical Engineering / Doctoral / Doctor of Philosophy

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