Orientador: Wilkens Aurelio Buarque e Silva / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-22T09:12:17Z (GMT). No. of bitstreams: 1 Prado_DevanirSilvaVieira_D.pdf: 1869734 bytes, checksum: 987fe805010f17dfcce41e55b62a20be (MD5) Previous issue date: 2013 / Resumo: O presente trabalho avaliou o comportamento mecânico de próteses fixas implantossuportadas submetidas às cargas oblíquas com 20 graus de inclinação. Foi confeccionado um corpo-de-prova em liga metálica à base de CoCr, simulando uma prótese fixa com dois cantiléveres, suportada por seis implantes separados pela distância de 10mm. Foram colados quatro extensômetros em cada um dos pilares (UCLA), um em cada face (mesial, distal, vestibular e lingual) e dois em cada cantilever. Após posicionamento da infra-estrutura e o torque nos parafusos, o conjunto foi submetido ao ensaio mecânico com carga compressiva oblíqua de 20 graus, com 15 Kgf na região do cantilever direito, a 7mm do pilar distal. A velocidade de aplicação de carga foi de 15 Kgf por segundo, com frequência de 0,5Hz totalizando 5 ciclos de aplicação. Foram avaliadas as deformações ocorridas em cada extensômetro de um mesmo pilar e em todos os pilares do corpo-de-prova. A média dos valores obtidos foi analisada pelos testes ANOVA e Tukey-Kramer, com significância de 5%. Diferenças significantes foram encontradas entre as faces de um mesmo pilar e entre as faces de todos os pilares avaliados (p<0,0001). Com aplicação da carga oblíqua no cantilever, o pilar adjacente foi o mais solicitado por compressão e os pilares mais anteriores da mesma forma em menor intensidade. Foi observado que os pilares anteriores foram submetidos ao regime de tração (alavanca) / Abstract: This study aimed to evaluate the mechanical behavior of implant-supported fixed prostheses, with oblique loads submitted to the 20° tilt. Was made in a body of evidence-based alloy CoCr, simulating a fixed prosthesis with two cantilever supported by six implants separated by a distance of 10mm. Four strain gauges were glued in each of the pillars (UCLA), one on each face (mesial, distal, buccal and lingual) and two on each cantilever. After the torque of the pillars and the infrastructure, the set was subjected to a mechanical test with oblique compressive loads of 20°, with 15Kgf in the region of the cantilever law, 7mm distal abutment. The rate of application of load was 15N per second at a frequency of 5 cycles totaling 0.5 HTZ applications. We evaluated the deformations occurring in each extensometer of one pillar in all pillars body of evidence. The mean values were analyzed by ANOVA and Tukey-Kramer, with a significance of 0.05. Significant differences were found between the faces of the same pillar and between the faces of all the pillars assessed (p <0.0001). With application of the cantilever load oblique, the adjacent pillar was the most requested by compressing and the pillars likewise earlier in smaller amounts. It was observed that the pillars were requested earlier also under traction (lever) / Doutorado / Protese Dental / Doutor em Clínica Odontológica

Orientador : Rolf Rode / Banca: Marcia André / Banca: Plínio Moroni / Banca : Antonio Olavo Cardoso Jorge / Banca: Sigmar de Mello Rode / Resumo: Este trabalho objetivou avaliar a microbiota bacteriana e fúngica das cavidades anoftálmicas, próteses oculares e olhos contralaterais de 43 usuários de prótese ocular em resina acrílica, unilateral, e relacionar a quantidade de secreção conjuntival presente nessas cavidades com a microbiota conjuntival, frequência de limpeza, tempo de uso e tempo decorrido desde o último polimento da prótese. Todos os pacientes apresentavam secreção conjuntival e microbiota Gram positiva nas cavidades anoftálmicas, Os microrganismos mais frequentemente isolados das 43 cavidades anoftálmicas, por ordem decrescente de freqüência, foram: Staphyfococcus coagulase negativos, Staphylococcus aureus, Candída albicans, Proteus mirabilis, Citrobacter koseriana, Streptococcus pyogenes, Pseudomonas aeruginosa, Enterobacter sakazakii e Enterobacter aerogenes. Microbiota Gram negativa foi isolada de oito cavidades e fúngica, de três. O estudo estatístico dos dados evidenciou relação não significativa entre a quantidade de secreção conjuntival e a presença de microbiota Gram negativa• nas cavidades; e entre a quantidade de secreção conjuntival e a frequência de limpeza da prótese ocular. Correlação, estatisticamente significativa, foi constatada entre a quantidade de secreção conjuntiva! e o tempo de uso e o tempo decorrido desde o último polimento da prótese / Abstract: The purpose of this work was to evaluate the bacterial and fungic microbiota of the anophthalmic sockets, ocular prosthesis and fellow eyes of forty three acrylic resin prosthesís carrying patients, and thereby relate the amount of conjunctival discharge to the presence of organisms, frequency of prosthesis cleaning, time of use and elapsed time since the last prosthesis polishing. All patients showed conjunctival discharge and Gram positive organisms in the anophthalmic sockets. The predominant organisms in the anophthalmic sockets were Staphylococcus coagulase negative, Staphylococcus aureus, Candida albicans, Proteus mirabilis, Citrobacter koseriana, Streptococcus pyogenes, Pseudomonas aeruginosa, Enterobacter sakazakii e Enterobacter aerogenes. Gram negative bacteria were found in eight anophthalmic sockets and fungi in three. No relation was found between the amount of the conjunctival discharge and the presence of Gram negative bacteria in the anophthalmic socket, nor with the frequency of prosthesis cleaning. However, there was a significant relation between the amount of conjunctival discharge and time of prosthesis use, as well as time elapsed since the last prosthesis polishing / Doutor

Orientador: Altair Antoninha Del Bel Cury / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-27T03:27:19Z (GMT). No. of bitstreams: 1 Ribeiro_LiviaForster_D.pdf: 4328252 bytes, checksum: 494acc1965c2ac87efb51ae7bd545445 (MD5) Previous issue date: 2015 / Resumo: A reabilitação com próteses fixas implantossuportadas na maxila é uma das melhores opções, quando indicada, sendo consagrada na literatura. Entretanto, devido à alta exigência estética nesta região, a reabilitação com implantes, unitária ou múltipla, é bastante desafiadora tanto para o profissional como para o paciente. Nesse sentido, não somente a estética, mas também os fatores mecânicos atuantes nessas reabilitações, são de extrema importância para a longevidade do tratamento. Dessa forma, o posicionamento e o número dos implantes a serem instalados na maxila anterior têm sido fatores decisivos no planejamento do caso, tanto sob o ponto de vista estético quanto mecânico. Nesse estudo foi avaliada a influência da quantidade e disposição dos implantes na distribuição de tensões nos implantes, componentes e reabilitação protética em diferentes disposições de implantes (04 implantes (4I), 02 implantes na região dos incisivos centrais (CS), 02 implantes sendo um no incisivo central e um no incisivo lateral oposto (CSLS), 02 implantes na região dos incisivos laterais (LS)) na região anterior da maxila, por meio do método tridimensional (3D) de elementos finitos (MEF). Foram obtidos quatro modelos 3D compostos pelas seguintes estruturas: região anterior da maxila (porção cortical e trabecular), implantes cilíndricos em titânio (3.75x11mm) de interface protética do tipo cone Morse, mini-pilares em titânio, infraestrutura em zircônia e coroas cerâmicas. O tecido ósseo e as coroas foram obtidas por meio de imagem tomográfica cone Beam. Os implantes, pilares e infraestrutura protética foram criados a partir do programa CAD (Computer Aided Design) SolidWorks®. Posteriormente os modelos foram exportados para o programa computacional de análises numéricas ANSYS Workbench® para análise e obtenção dos resultados. Foi utilizado um carregamento de 150N, distribuídos nas faces palatinas das coroas protéticas, a 45° em relação ao longo eixo das coroas. Os dados obtidos mostraram a distribuição de tensões e os maiores e menores valores de tensões equivalentes de von Mises (MPa) de cada modelo. O número de implantes revelou uma importante influência no comportamento mecânico das reabilitações e demais componentes, justificados pelos menores valores de tensão encontrados no modelo 4I, em todos os seus componentes (112MPa/Implantes, 93MPa/Pilares, 61MPa/Infraestrutura e 53 MPa/coroas cerâmicas). Todavia, quando o número diminuiu para dois implantes, como visto no modelo LS, constatou-se uma maior concentração de tensão em todas as estruturas avaliadas (654MPa/Implantes, 716 MPa/Pilares, 200 MPa/Infraestrutura e 182 MPa/coroas cerâmicas). O modelo CS, e o modelo CSLS mostraram comportamento mecânico semelhantes entre si, porém com valores de tensão menores que o modelo LS e maiores que o modelo 4I (295 e 412 MPa/Implantes, 174 e 228 MPa/Pilares, 195 e 80 MPa/Infraestrutura e 121.17 e 107 MPa/coroas cerâmicas respectivamente). Conclui-se que um número maior de implantes para suportar próteses parciais fixas, distribui as tensões incididas nos implantes e componentes, de maneira mais uniforme e em menores quantidades, o que pode sugerir, que do ponto de vista mecânico, uma maior longevidade do tratamento reabilitador da região anterior da maxila / Abstract: : The oral rehabilitation with implant-supported fixed prosthesis in the maxilla is the most suitable option and is widely enshrined in the literature. Due to the high requirement aesthetics in this area, the rehabilitation with implants, single or multiple, is a big challenge for both the professional and the patient. In this sense, not only the aesthetics but also the mechanical factors acting in these rehabilitations are very important to the longevity of treatment. Thus, the positioning and the number of the implants to be installed in the anterior maxilla have been decisive factors in the planning of the case, both from the aesthetic and mechanical point of view. In this study was evaluated the influence of the number and the arrangement of the implants in stress distribution in the implants, components and prosthetic rehabilitation in different arrangements (04 implants (4I), 02 implants in the region of the central incisors (CS), 02 implants being one the central incisor and the opposite lateral incisor (CSLS) implants 02 in the region of the lateral incisors (LS)) in the anterior maxillary area by means of the method three-dimensional (3D) finite element method (FEM). The 3D models were obtained and they contained the following structures: anterior maxillary region (cortical and trabecular bone), cylindrical titanium implants (3.75x11mm) prosthetic interface type Morse taper, abutments in titanium alloy, zirconium framework and ceramic crowns. Bone tissue and the crowns were obtained by tomographic cone Beam image. The implants, abutments and prosthetic framework were created from the CAD computer software (Computer Aided Design) SolidWorks®. Subsequently the models have been exported to the computer software of numerical analysis ANSYS Workbench® for analysis and achievement of results. The magnitude of the force applied on each unit was 37,5N distributed on the palatine faces of the prosthetic crown, at a 45° angle to the long axis of each crowns, i.e. the total load applied to the prosthesis was 150N. The data obtained emphasized the stress distribution and the higher stress values the equivalent von Mises (MPa) of each model. The number of implants revealed a significant influence on the mechanical behavior of rehabilitation and other structures, justified by the lower stress values found in the model 4I, in all its components (112 MPa/Implants, 93 MPa/Abutments, 61MPa/Framework and 53 MPa/Ceramic crowns). However, when the number has decreased to two implants, as seen in the LS model, there was a higher concentration of tension in all the evaluated structures (654MPa/Implants, 716 MPa/Abutments, 200 MPa/Framework and 182 MPa/Ceramic crowns). The CS and the CSLS models showed similar mechanical behavior to each other, but with lower stress values that the LS model and larger than the 4I model (295 and 412 MPa/Implants, 174 and 228 MPa/Abutments, 195 and 80 MPa/Framework and 121.17 and 107 MPa/Ceramic crowns respectively). It was concluded that a larger number of implants to support a FPPs, distributed the stresses on the implants and in the structures more evenly and in a smaller amounts, which might suggest the greater longevity of the rehabilitation of treatment especially under the mechanical point of view / Doutorado / Protese Dental / Doutora em Clínica Odontológica

A viabilidade da utilização de próteses modulares cimentadas em diáfises de fêmur em cães foi demonstrada, porém diversos autores relatam a falha de aderência entre as próteses e os ossos como uma das principais complicações. O presente trabalho teve como objetivo investigar biomecanicamente a interface implante metálico, osso e capa de cimento ósseo de com diferentes espessuras de cimento ósseo utilizadas para a estabilização da prótese. Para tanto foram utilizados fêmures bilaterais de 24 cadáveres de cães com peso acima de 15 quilos que foram divididos em quatro grupos, o primeiro grupo composto por oito fêmures utilizou uma espessura de capa de cimento de 1,0 a 1,5 mm, o segundo grupo, composto por oito fêmures, utilizou uma capa de cimento de 2,0 a 2,5 mm e o terceiro grupo, composto por oito fêmures, utilizou uma capa de cimento compreendida entre o intervalo de 3,0 a 3,5 mm de espessura. Os fêmures foram submetidos a ensaios destrutivos de torção onde foram avaliados a rigidez à torção e torque máximo suportado pela interface implante metálico, osso e capa de cimento ósseo. O quarto grupo, denominado de controle, composto pelos fêmures contralaterais íntegros, foram submetidos ao mesmo ensaio de torção que as peças onde foram utilizadas as próteses. Os resultados encontrados foram que nas condições apresentadas neste estudo não foi encontrada diferença biomecânica estatisticamente significante, em relação à rigidez à torção e torque máximo, na utilização de capas de cimento na faixa de 1 mm e 2,5 mm e entre 2 mm e 3,5 mm. Porém houve diferença quando comparado as faixas de espessura de cimento entre os grupos de 1 mm a 1,5mm e de 3 mm a 3,5 mm. / The feasibility of modular cemented prosthesis in the femoral diaphysis was demonstrated in dogs, but several authors report loosening of bone, cement and implant interface as a major complication. The objective of this study was to evaluate the stabilization of the prosthesis using different thicknesses of cement layer. For this study 48 femurs from 24 dogs weighing over 15 kilograms were used. They were separated in four groups, the first group with eight femurs used a cement mantle from 1.0 to 1.5 mm, the second group, with eight femurs, used a cement mantle from 2.0 to 2.5 mm and the third group, with eight femurs, used a cement layer from 3.0 to 3.5 mm. The femurs were submitted to destructive torsion tests where they were evaluated due to the values of torsional rigidity and maximum torque shown by the implant, bone and bone cement interface. In the fourth group were the remaining intact femurs, they were evaluated using the same torsion test used on the other groups. The results were that under the present conditions we found no biomechanical differences relative to torsional rigidity and maximum torque, using cement layers between 1 mm and 2.5 mm and between 2 mm and 3.5 mm. But we found biomechanical differences between groups of 1 mm to 1.5 mm and 3 mm to 3.5 mm.

The e-OPRA Implant System (Integrum AB, Sweden) is a system which employs permanently accessible implantable neuromuscular electrodes in combination with osseointegrated attachment of the prosthesis to the skeleton, in order to create a more natural control of advanced robotic upper-limb prostheses. The system enables the possibility of sensory feedback, via a cuff electrode to the ulnar nerve which allows for direct neurostimulation of the nerve. This work proposes a method using electroencephalography (EEG) to quantitatively evaluate the cognitive workload of a person controlling a prosthesis, and how said workload changes when sensory feedback is enabled. Based on previous studies on EEG and cognitive workload, the proposed methods include collecting EEG data from subjects who are performing a grasping task while listening to a selection of sounds and counting the number of times a specific tone is presented. The data is analysed using both event related potentials (ERPs) as well as spectral analysis. The method was used in a trial run consisting of two healthy subjects, and one transhumeral amputee implanted with the e-OPRA system. Although the subject group was not large enough to draw any statistical conclusions, the trial run and the results from it suggest that the methods could be used in a larger study to evaluate the cognitive workload of amputees implanted with the e-OPRA system.

<p>This study explored the history, present status, and future trends in assistive technologies and innovations in lower limb prosthesis. The study analyzed trends in patent filing and looked into how mainstream technologies such as additive manufacturing, advanced materials and robotic integrate with other enabling technologies such as IoT, AI, sensors etc. to advance technology innovation and improve the quality of life of people with limb impairment.</p> <p><br></p> <p>This research study is significant in helping to understand what is on the horizon for people with lower limb impairment given that this population tend to be neglected and their needs have not been fully addressed in many areas</p>

Thesis: B.S., Massachusetts Institute of Technology, Department of Biology, 1977 / by Gene Paul Masters. / B.S. / B.S. Massachusetts Institute of Technology, Department of Biology

The great toe is the part of the foot that most often requires surgical intervention. The first metatarsophalangeal joint (FMTPJ) is the most prominent joint of the great toe. Primary causes of FMTPJ failure are rheumatoid arthritis, osteoarthrosis and joint degeneration secondary to deformities such as hallux valgus, hallux rigidus or the trauma of previous surgery. FMTPJ prostheses are used to restore a measure of motion, correct deformities and relieve pain. FMTPJ replacement is most often indicated for elderly and less active patients but is contra-indicated for young, rheumatoid and active patients. The most common types of FMTPJ prostheses are made from silicone elastomer. Although these have been in use since the 1960's, there are many problems associated with these and all other types of FMTPJ prostheses. For example, recent research has shown that silicone elastomer metatarsophalangeal arthroplasties may cause severe, chronic silicone granulomatous disease. Also, previous studies of the pressure distribution under normal feet, and pathological feet before and after surgery, can be used to show that FMTPJ prostheses fail to restore normal weight-bearing. In this regard, FMTPJ arthroplasties perform little better than amputation. The reasons for the poor biomechanical performance of FMTPJ arthroplasty are not well documented. Existing theoretical models of FMTPJ function cannot be used to explain why almost all surgery of the first ray causes weight bearing to transfer to the lateral side of the foot. A new hypothesis of FMTPJ function was therefore formulated. It is known that the motions of the FMTPJ are linked to motions of the other bones of the foot and ankle because the strong fibrous tissues of the plantar aponeurosis connect the hallux to the calcaneus. However, it is hypothesised that the particular orientation of the bones at the final stages of the stance phase is crucial to the weight-bearing functions of the FMTPJ. A specification for a new prosthesis was therefore developed in accordance with the biomechanical principles contained in the hypothesis. Various potential designs of prosthesis were investigated, but a ball-and-socket configuration was selected because it appeared to allow the motions necessary to restore normal loading in the foot. Three slightly different prototype ball-and-socket FMTPJ prostheses were designed and manufactured. These prototypes were inserted into cadavers; which allowed the range of motion of the prototype prostheses to be assessed in relation to the constraints imposed by the strong fibrous attachments in the foot. Some of the rudimentary surgical techniques and the instruments required to insert and align the prostheses were developed. The various design features that had been incorporated in the different prototypes were assessed in terms of their relevance to ultimate performance of the arthroplasty. In order to verify the biomechanical design principles, cadaveric FMTP joints were tested for range of motion before and after inserting the prostheses. The results were compared to the range of motions obtained from a dry bone specimen, and to the most successful FMTPJ design to date- a double-stem silicone elastomer prosthesis. Finally, the results from all the tests were compared and discussed in relation to the original hypothesis about the function of the great toe. The results obtained from the new prosthesis were sufficiently encouraging to be able to recommend that the prototype be manufactured for further clinical trials. The new prosthesis was found to simulate the conditions that are necessary to re-establish normal weight-bearing patterns in the foot; such as an elevated centre of rotation for the proximal end of the first metatarsal bone, tension in the plantar aponeurosis, mobile bones in the arch, and weight-bearing by the first metatarsal. Previous prostheses used in FMTPJ arthroplasty are believed to be inadequate in that they do not restore at least one of these conditions, which ultimately lead to implant failure. Within the limits of cadaver trials, the new design has demonstrated that it has the potential to succeed.

Powered prostheses are at the forefront of prosthetic technology, improving functionality by providing positive power to joints in the absence of native anatomy. Currently, there is no commercially available powered solution for hip-level amputees, and most hip prostheses are mounted to the front of the prosthetic socket. This thesis designed, fabricated, and tested a novel Laterally Mounted Powered Hip Joint (LMPHJ) that augments user gait to promote improved walking patterns. The LMPHJ attaches to the lateral side of the prosthetic socket, locating the hip centre of rotation closer to the anatomical location while ensuring user safety and stability. The new design locates the motor and all electronics in the thigh area, thereby maintaining a low profile while transmitting the required hip moments to the joint centre of rotation. A prototype was designed and manufactured to evaluate LMPHJ performance. Mechanical testing followed the ISO 15032:2000 standard and successfully demonstrated the joint's resistance to everyday loading conditions. Functional testing involved integrating the LMPHJ, Ossur Rheo Knee, and Ossur Pro-Flex XC with a prosthesis simulator that allowed three able-bodied participants to walk with the powered prosthesis successfully. This validated the mechanical design for walking over level ground and demonstrated that the LMPHJ is ready for next phase evaluation with hip disarticulation amputee participants.

Intracortical brain-computer interfaces (BCIs) provide the means to do something extraordinary: restore movement to patients with paralysis or amputated limbs. Realizing this potential requires the development of decode algorithms capable of accurately translating measurements of neural activity, in real time, into appropriate time-varying commands for an external device (e.g. prosthetic limb). This problem is fundamentally interdisciplinary, drawing on tools and insights from engineering, neuroscience, statistics, and computer science, among others. Decode algorithms that have been favored historically tend to be computationally efficient, but perform suboptimally, likely because their assumptions fail to fully and accurately capture the complexity in neural population responses. Recent work harnessing the power of contemporary machine learning methods has raised the performance bar, yet these methods can be computationally demanding and it is unclear what properties of neural and/or behavioral data they exploit. In this dissertation, we characterize properties of motor-cortex population geometry and let these properties dictate decoder design, resulting in methods that perform very well, yet retain the benefits of simpler methods. We use this approach to develop a closed-loop navigation BCI, and to design a highly accurate, general, and interpretable decoder. The properties described in this dissertation have implications for any BCI. By designing decoders to explicitly respect (and leverage) these properties, we can construct powerful yet practical BCIs that better meet the needs of patients.