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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.
311

\"Estudo longitudinal da força de mordida em pacientes portadores de próteses parciais fixas sobre implantes osseointegrados: comparação entre áreas dentadas e implantadas\" / Bite force longitudinal study on patients wearing implant-supported partial prothesis

Renan Hollanda Fileni 22 March 2007 (has links)
A proposta deste estudo foi analisar o desenvolvimento da força máxima de mordida em um grupo de pacientes que recebeu próteses parciais fixas sobre implantes (PPFSI) nas regiões de molares, pré-molares até caninos e incisivos antagonizando com dentes naturais e comparar os resultados obtidos com as áreas dentadas do mesmo grupo de pacientes, durante um período de 64 meses (5,3 anos). As forças de mordida foram medidas em cinco regiões da boca: molares em ambos os lados, pré-molares ou caninos em ambos os lados e incisivos; nas áreas de próteses sobre implantes e também nas áreas de dentes naturais. Para tanto, foi usado um transdutor medidor de força de mordida, que tem como princípio de funcionamento uma célula de força colada a um garfo de mordida, amplamente usado na literatura e sempre operado pelo pesquisador. As medições foram feitas imediatamente após a instalação das próteses, 3, 30 e 64 meses depois. Comparando o desenvolvimento das forças de mordida entre as áreas implantadas e de dentes naturais encontra-se já no primeiro controle, após 3 meses de instalação, um aumento das forças de mordida nas próteses sobre implantes instaladas na região de molares que supera as forças desenvolvidas por dentes naturais na mesma região. Para as próteses instaladas na área de incisivos, ao contrário, não foi registrado aumento estatístico destas forças, havendo uma tendência em permanecerem menores quando comparadas às forças desenvolvidas nas mesmas regiões por dentes naturais. Na região de pré-molares ou caninos não houve aumento estatístico de força nas PPFSI. Quando analisadas as áreas dentadas dos pacientes, não houve mudança estatística de força de mordida em nenhuma das regiões durante todo o experimento. / This study proposal was to analyse the changes on the maximal bite force on a patients sample who had implant-supported partial fixed prosthesis (FPP) installed and the results were compared to the ones obtained from the dentate areas on the same sample. Sixteen patients were followed for sixty-four months (5.3 years) and the bite forces were measured on the mouth regions which the prosthesis were installed (molars and premolars up to canines and incisors regions). This measured occurred on five regions of the mouth: both side molars, pre-molars or canines and incisives; either on the places it had a implant as well as on the natural teeth area. In order to do that, it was used as a measuring device, a largely used apparatus which consisted of a biting fork provided with a strain gauge. The bite forces recordings were made at the time of prosthesis installation, after 3, 30 and 64 months thereafter. It was found a bite force increase in the initial period of 3 months after the prosthesis installation in the area of FPP in the molar regions. In this period the bite forces became higher than in dentate situation in the same region and it manteined on this level until the final of the experiment. Comparing the bite straight development between the implanted areas and the natural teeth areas, we found a bite force increased on the prostheses installed over the molars region that overcome the straight development for natural teeth on the same area. On the other hand, for the prostheses installed on the incisive areas, we had not found a statistical straight increased. Actually, it was a tendency to keep smaller than the straight developed on the same regions by natural teeth. On premolars regions or canines, there was not a straight statistical increased on PPFSI. When we analyze the patients? teeth areas, there was not a statistical bite increase on any of the premolars or canines regions during the entire experiment.
312

Análise da distribuição das tensões através de prótese fixa implanto-suportada e dento-implanto-suportada em hemi-mandíbulas de canis familiaris mediante o método de interferometria holográfica de dupla exposição / Stress analysis of tooth-implant and implant supported prosthesis in dog mandibles. Holographic interferometry double exposition method

José Eduardo Chorres Rodriguez 20 September 2005 (has links)
Este estudo objetivou pesquisar a distribuição das tensões através de próteses fixas implanto-suportadas e dento-implanto-suportadas em hemi-mandíbulas de canis familiaris mediante o método de interferometria holográfica de dupla exposição. Três cães foram selecionados e colocados três implantes em cada um deles (hemi-mandíbula direita: um implante e na hemi-mandíbula esquerda: dois implantes). Após a espera de dois meses, os dois tipos de próteses foram fixados sobre os implantes e os animais sacrificados. A seguir, as hemi -mandíbulas foram extraídas e fixadas no dispositivo especialmente desenhado para tal fim (CAMPOS, 2001). Todo o sistema foi colocado sobre uma mesa holográf ica e carga estática foi aplicada sobre três posições previamente estabelecidas nas próteses (sobre o pilar anterior, ponto médio da barra e pilar posterior). 18 hologramas foram obtidos mediante a técnica holográfica. A análise dos hologramas revelou que de forma geral, as hemi-mandíbulas com próteses dento-implanto-suportadas sofreram maior tensão quando comparadas com as hemi-mandíbulas com próteses implanto-suportadas. Em relação às próteses, as implanto-suportadas foram aquelas que melhor distribuíram os esforços quando comparadas com as dento-implanto-suportadas. / The aim of this study was to investigate the stress distribution of tooth-implant and implant supported prosthesis in dog mandibles by means of holographic interferometry double exposition method. Three mongrel dogs were selectioned and three osseointegrated implants were placed (right hemi-mandible: one implant and in the left hemi-mandible: two implants). After two months, both prostheses were fixed on the implants and the animals were sacrificed. The hemi-mandibles were fixed in a special device (CAMPOS, 2001) and placed on the holographic table. A static load was applied on three different positions on the prosthesis (anterior abutment, midpoint of the bar and posterior abutment) and eighteen holograms were obtained. The hologram analysis revealed that the hemi-mandibles with tooth-implant prosthesis transmitted more tension that the hemi-mandibles with implant supported prosthesis. In addition to, an equal distribution of stress were observed in the implant supported prosthesis when compared with the tooth-implant prosthesis.
313

Exploring decision making and patient involvement in prosthetic prescription

Semple, Karen January 2015 (has links)
Background Recent conflicts have seen an increase in trauma related military amputees who incur complex injuries which result in varied residual limbs. In many cases these amputees have been provided with state of the art (SOTA) components with the expectation that they will transfer into NHS care after military discharge. However, there is a lack of knowledge around how prosthetic prescriptions are made in both the MOD and NHS, including patient involvement. It is important to explore prosthetic prescription decisions to enhance the quality, consistency and equity of care delivery for trauma amputees. This thesis explores decision making in prosthetic care for trauma amputees in the UK during this period of change. Aims To explore aspects of prosthetic care provision in the UK including clinical decision making, patient experience and the transition of prosthetic care from the MOD to the NHS. Design An exploratory qualitative project informed by decision making and patient involvement theory. Semi-structured interviews were carried out with nineteen clinical staff involved in prosthetic provision, six civilian and five veteran trauma amputees. Thematic analysis was used to analyse the data. Findings Prosthetists used a wide range of factors in making prescription decisions, including physical characteristics, patients’ goals, and predicted activity levels. Prescription decision making varied depending on the prosthetists’ level of experience and the different ‘cues’ identified. In some cases there was a lack of transparency about drivers for the prescription choice. Prescription decisions are influenced by long term relationships between prosthetist and patient, allowing a trial and error approach with increasing patient involvement over time. Patient experiences of their trauma amputation influenced their approach to rehabilitation. Patients reported wanting different levels of involvement in their prosthetic care, however, communication was essential for all. Veteran amputees benefited from peer support opportunities which NHS services were less conducive to. However, NHS amputees were more likely to have been ‘involved’ in care decisions. The expectations that MOD patients had of inferior care in the NHS were not realised in the majority of veteran cases. Recommendations Research is needed to support prosthetists’ decisions to become more consistent and transparent. The NHS should consider introducing a peer support model for trauma patients, and particularly in the early stages of rehabilitation.
314

Využití aditivní technologie pro návrh a výrobu prototypu oční protézy / Use of additive technology for the design and production of eye prosthesis prototype

Vocílka, Ondřej January 2019 (has links)
This diploma thesis has an aim to fabricate a prototype of esthetical prosthesis using solely Rapid Prototyping aditive technology and to explore the possibility of using commercially available biocompatible materials. In the theoretical part, a description of types of ocular prosthesis types with the focus being on esthetic ocular prosthesis. is given. The practical part of the work offers a comprehensive view on the whole process of the prototype fabrication. It provides a description of creating the 3D model by scanning, geometrical adjustments of the model, textures mapping, print optimization and the printing itself. The closing part of the thesis consists of a discussing focused on an evaluation of the fabricated prototype followed by technical-economical assesment, a proposal of next steps, and a proposal of current usage of the created method.
315

Deformačně-napěťová analýza protézy dolní končetiny / Stress-strain analysis of lower limb prosthetic

Musilová, Kateřina January 2010 (has links)
This master thesis deals with lower-limb prosthesis. The aim of the first part of this work is stress-strain analysis of trans-tibial prosthesis, which is understand without prosthetic socket and the foam prosthetic feet. Analysis is made using finite element method in ANSYS Workbench 12.0 software. For the purpose of setting up the computational model it is necessary to make few partial models. Model of geometry of the prosthesis is made in SolidWorks 2009. Based on the outputs of stress-strain analysis and the results evaluation, the critical component is chosen and this one is evaluated according to limite state for fatigue. The algorithm of evaluation of named component in the state of high cycle fatigue is discussed in the second part of this thesis.
316

Prosthetic Control using Implanted Electrode Signals

Hákonardóttir, Stefanía January 2014 (has links)
This report presents the design and manufacturing process of a bionic signal messagebroker (BSMB), intended to allow communication between implanted electrodes andprosthetic legs designed by Ossur. The BSMB processes and analyses the data intorelevant information to control the bionic device. The intention is to carry out eventdetection in the BSMB, where events in the muscle signal are matched to the events ofthe gait cycle (toe-o, stance, swing).The whole system is designed to detect muscle contraction via sensors implantedin residual muscles and transmit the signals wireless to a control unit that activatesassociated functions of a prosthetic leg. Two users, one transtibial and one transfemoral,underwent surgery in order to get electrodes implantable into their residual leg muscles.They are among the rst users in the world to get this kind of implanted sensors.A prototype of the BSMB was manufactured. The process took more time thanexpected, mainly due to the fact that it was decided to use a ball grid array (BGA)microprocessor in order to save space. That meant more complicated routing and higherstandards for the manufacturing of the board. The results of the event detection indicatethat the data from the implanted electrodes can be used in order to get sucient controlover prosthetic legs. These are positive ndings for users of prosthetic legs and shouldincrease their security and quality of life.It is important to keep in mind when the results of this report are evaluated that allthe testing carried out were only done on one user each.
317

Sensor Fusion for Closed-loop Control of Upper-limb Prostheses

Markovic, Marko 18 April 2016 (has links)
No description available.
318

An Evaluation of Digital Methods in Reverse Engineering Using Selected Medical Applications

Parrott, Andrew Mark 17 November 2006 (has links)
Student Number : 9710738R - MSc (Eng) dissertation - Faculty of Engineering and the Built Environment / This dissertation investigates the use of digital modeling methods for selected medical applications. The digital methods include the design of a cranial implant, auricular prosthesis and the duplication of an oral prosthesis. The digital process includes imaging, image processing, design and fabrication steps. Three types of imaging used are contact and non-contact measurement systems and CT scanning. The investigation uses a Phantom haptic device for digital design. The implants and prostheses are fabricated using a Thermojet printer and investment casting. Traditional and digital processes are compared using four case studies on selected criteria. The conclusions of the investigation are that a digital process can be used and is equal to or better than traditional methods in prosthesis and implant design.
319

"Estudo experimental da transmissão da pulsatilidade da endoprótese à parede do aneurisma da aorta após correção endoluminal" / Pulsatility transmission from endograft to aortic aneurysm wall after endovascular repair : an experimental study

Orra, Hussein Amin 26 September 2005 (has links)
Objetivo: Medir a pulsatilidade da parede do aneurisma de aorta humano antes e depois de sua correção endoluminal. Método: Cinco aneurismas foram submetidos à perfusão pulsátil antes e depois do implante de uma endoprótese. Resultado: o nível da coluna de água oscilou durante a pulsação com variações de 17, 16, 13, 7 e 25 cm antes da colocação da endoprótese. Depois da prótese, a oscilação diminuiu em todos os casos para 13, 12, 9, 3,5 e 23 cm, respectivamente. Conclusão: A pulsação da endoprótese é transmitida à parede do aneurisma / Objective: To measure the pulsatility of human aortic aneurysms before and after exclusion with endograft. Method: Five aneurysms were submitted to pulsatile perfusion before and after implantation of a bifurcated endograft. Result: The level of the water column oscillated during pulsation, in each case, with an amplitude of 17, 16, 13, 7 and 25 cm before the endograft insertion. After that, the amplitudes dropped to, respectively 13, 12, 9, 3.5 and 23 cm.Conclusion: Pulsation of an endograft is transmitted to the aneurysm wall even in the absence of endoleak
320

Análise comparativa da interface entre intermediários e estruturas fundidas e CAD/CAM em Co-Cr e zircônia antes e após queima de cerâmica e ciclagem mecânica / Comparative analysis of the interface between different abutments and casted or CAD/CAM prostheses before and after ceramic firing and behavior after mechanical cycling.

Coró, Vitor 05 July 2013 (has links)
As próteses sobre implantes apresentam alto índice de sucesso, mas ainda existem relatos de complicações técnicas e mecânicas, principalmente em relação à adaptação e desaperto de parafusos. Técnicas CAD/CAM foram desenvolvidas tentando melhorar adaptação e passividade, e hoje existem vários materiais e sistemas como opção de trabalho. A proposta deste estudo foi avaliar, por meio de leitura em microscópio, a adaptação de próteses de três elementos sobre dois implantes confeccionadas em diferentes materiais, por diferentes técnicas, antes e após a queima de cerâmica. Também foi verificado se o método/material utilizado, assim como o grau de adaptação influenciariam no comportamento das peças frente a um ensaio de fadiga mecânica. Foram formados 5 grupos de 10 amostras (n=10). Após leituras, prensagem de cerâmica e ensaio de fadiga, os dados foram submetidos aos testes ANOVA e Tuckey-Kramers. As médias de desajuste vertical pré e pós aplicação da cerâmica (μm), quando ambos parafusos apertados foram para G1: Estruturas fundidas em Co-Cr com cilindros calcináveis (26,03 ± 18,4) e (36,5 ± 9) G2: Estruturas sobrefundidas em liga de Co-Cr, utilizando cilindros com base de Co-Cr (4,86 ± 5) e (10,5 ± 6); G3: Estruturas fundidas em liga de Co-Cr, associadas à técnica do cilindro cimentado (0 ± 0)e (0 ± 0); G4: Estruturas usinadas em Co-Cr CAD/CAM (0 ± 0) e (2,7 ± 2);G5: Estruturas usinadas em Zircônia CAD/CAM (14,87 ± 9) e (15,2 ± 8). Para a condição de medida com apenas um dos lados apertado, pré e pós cerâmica, do lado parafusado, os resultados foram para G1: 9,63 ± 1 e 34,8 ± 8; G2: 2,37 ± 5 e 11,9 ± 9; G3: 0 ± 0 e 0 ± 0; G4: 0 ± 0 e 3,4 ± 3; G5: 17,69 ± 1 e 20,8 ± 9. Para a condição de medida com apenas um dos lados apertado, pré e pós cerâmica, do lado desparafusado, os resultados foram para G1: 124,22 ± 37 e 129,8 ± 37; G2: 64,79 ± 47 e 80,6 ± 46; G3: 12,34 ± 17 e 2,1 ± 3; G4: 3,54 ± 5 e 17,6 ± 8; G5: 37,77 ± 25 e 42,4 ± 19. O torque de desaperto (Ncm) dos parafusos protéticos foi verificado antes e após ensaio de fadiga com 300.000 ciclos. Os valores médios encontrados foram respectivamente: G1: 5,80 ± 1,23 e 4,11 ± 1,16; G2: 6,30 ± 1,00 e 3,32 ± 0,87; G3: 5,63 ± 1,05 e 3,30 ± 1,46; G4: 7,24 ± 1,05 e 3,44 ± 1,62; G5: 7,75 ± 1,25 e 6,78 ± 1,18. Os grupos CC, Co-Cr CAD/CAM e Zi, apresentaram os melhores resultados quanto ao ajuste vertical, seguidos pelo grupo Co-Cr e calcinável. Os grupos CC, Co-Cr e Co-Cr CAD/CAM apresentaram perda de torque dos parafusos protéticos após oensaio de fadiga mecânica. O grupo Zi teve menor perda de torque entretodos grupos, comparando antes e após o teste de fadiga. Nenhum dos grupos apresentou perda de torque suficiente para que a prótese perdesse estabilidade da junção. / The implant-supported prostheses present a high success rate, but there are still reports of technical and mechanical complications, mainly regarding adaptation and loosening of screws. CAD/CAM techniques have been developed trying to improve adaptation and passivity, and today there are many options of materials and systems to work with. The purpose of this study was to evaluate, by microscope, fitting of three elements prostheses retained by two implants, made of different materials, different techniques, before and after ceramic firing. It was also verified if the method/material used, as well as the degree of adjustment would influence on the behavior of the prostheses after a fatigue test. Five groups of ten specimens were formed (n = 10). After reading, ceramic pressing and fatigue test data were submitted to ANOVA and Tukey-Kramer\'s tests. The mean vertical misfit pre and post application of ceramic (μm), whit both screws tightened to G1: Structures casted in Co-Cr with castable cylinders (26.03 ± 18.4) and (36.5 ± 9) G2: Structures casted in Co-Cr, with Co-Cr basis cylinder (4.86 ± 5) (10.5 ± 6); G3: Structures casted in Co-Cr associated with the cemented cylinder technique (0 ± 0) and (0 ± 0); G4: Machined structures in Co-Cr CAD/CAM (0 ± 0) and (2.7 ± 2), G5: Structures machined in zirconia CAD/CAM (14.87 ± 9) and (15.2 ± 8). To the measurement condition of only one side tighted, pre and post ceramic, on the tightned side, the results were G1: 9.63 ± 1 and 34.8 ± 8; G2: 2.37 ± 5 and 11.9 ± 9; G3: 0 ± 0 and 0 ± 0; G4: 0 ± 0 and 3.4 ± 3; G5: 17.69 ± 1 and 20.8 ± 9. To the measurement condition of only one side tightened, pre and post ceramic, on the untightened side, the results were in G1: 124.22 ± 37 and 129.8 ± 37; G2: 64.79 ± 47 and 80.6 ± 46; G3: 12.34 ± 2.1 and 17 ± 3; G4: 5 ± 3.54 and 17.6 ± 8; G5: 37.77 ± 25 and 42.4 ± 19. The loosening torque of the prosthetic screws (Ncm) was checked before and after fatigue test to 300,000 cycles. The mean values were: G1: 5,80 ± 1,23 e 4,11 ± 1,16; G2: 6,30 ± 1,00 e 3,32 ± 0,87; G3: 5,63 ± 1,05 e 3,30 ± 1,46; G4: 7,24 ± 1,05 e 3,44 ± 1,62; G5: 7,75 ± 1,25 e 6,78 ± 1,18. CC groups, Co-Cr CAD/CAM and Zi, showed the best results regarding vertical adjustment, followed by the Co-Cr group and castable. CC groups, Co-Cr and Co-Cr CAD/CAM presented loss of torque after fatigue test. The Zi group showed less loss of torque among all groups, comparing before and after fatigue test. None of the groups showed enough loosening to loose joint stability.

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