O objetivo deste estudo foi verificar a hipótese que condições orais (uso de prótese dentária removível, machucados recorrentes devidos a prótese mal adaptada ou a dentes mal posicionados ou quebrados, consumo freqüente de bebidas quentes e escovação dentaria irregular ou pouco freqüente) poderiam interagir com tabaco, álcool, padrão alimentar e condição socioeconômica na carcinogênese oral. Foi realizado estudo de caso-controle de base hospitalar (Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo), com 124 pacientes (22 mulheres e 102 homens) com câncer de boca e igual número de controles sem experiência de câncer atendidos no mesmo hospital para condições não relacionadas à boca. Os pacientes do grupo caso apresentavam neoplasia em diferentes sítios da boca: mucosa jugal (5), área retromolar (6), lábio inferior, aspecto interno (10), gengiva (11), palato (17), assoalho bucal (27) e língua (48). A seleção dos pacientes do grupo controle observou pareamento individual por sexo e idade (± cinco anos) com o grupo caso; e pareamento por freqüência quanto à condição de fumantes ou ex-fumantes (não-fumantes não foram incluídos no estudo). Todos os participantes do estudo responderam um questionário detalhando características sócio-demográficas, padrão de consumo de bebidas alcoólicas e tabaco, hábitos alimentares e informações sobre as condições orais de interesse do estudo. A análise estatística usou modelos multivariados de regressão logística condicional, com estrutura hierárquica dos níveis de determinação. Como resultado desse procedimento de análise, indicou-se que o uso de prótese dentária não associou com câncer de boca (p=0,090); no entanto, a lembrança de feridas recorrentes na mucosa oral devido ao uso de prótese mal adaptada teve associação positiva com a chance da doença (p=0,007). A lembrança de machucados por dentes quebrados ou fora de oclusão não associou com câncer de boca em fumantes (p=0,084). A associação entre câncer de boca e consumo de bebidas quentes ficou no limiar da significância estatística (p=0,050). Machucados recorrentes na mucosa oral, devido a próteses mal adaptadas pode ser um fator que contribui com a carcinogênese dos tumores da boca em fumantes; e esse resultado não seria devido à falta de controle pelos demais fatores relevantes na determinação do câncer bucal. / The aim of this study was to assess the hypothesis that conditions of mouth status (the use of dentures, recurrent sores by ill-fitting dentures or ill-positioned or broken teeth, frequent intake of hot beverages and irregular or infrequent tooth brushing) may interact with tobacco, alcohol, diet and socioeconomic status in the carcinogenesis of oral cancer. We performed a hospital-based (\"Hospital das Clínicas\", School of Medicine, University of São Paulo) case-control study comprising 124 patients (22 women and 102 men) with oral cancer, and the same number of controls without previous or current experience of cancer and with treatment needs unrelated to mouth status. Patients in the case group presented tumors at different sites of the mouth: cheek mucosa (5), retromolar area (6), lower lip, inner aspect (10), gum (11), palate (17), floor of mouth (27) and tongue (48). The selection of controls observed the concurrent pairing for gender and age (± five years) with cases, and matching by frequency by smoking status: current or former smokers (never-smokers were not included in the study). All participants responded a detailed questionnaire on socio-demographic characteristics, patterns of alcohol and tobacco consumption, dietary habits and information on conditions of mouth status. Data analysis used multivariate models of conditional logistic regression, observing a hierarchical structure of levels of determination. As a result of this analytical scheme, the use of dentures was reported as not associated with the adjusted odds of mouth cancer (p=0.090). When adjusted by covariates on smoking, alcohol drinking and diet, the association of recurrent sores caused by ill-fitting dentures with the odds of mouth cancer was significant (p=0.007). However, recurrent sores by defective teeth were not indicated as a significant contributing factor for the odds of oral cancer in smokers. The association between mouth cancer and the frequent intake of hot beverage was assessed at the threshold of significance (p=0.050). Recurrent oral sores due to ill-fitting dentures may be a contributing factor for the carcinogenesis of mouth neoplasms in smokers; and this result is unlikely to be due to insufficient control of covariates.

O presente estudo avaliou próteses vasculares de pequeno calibre feitas de polidimetilsiloxano (PDMS) com reforço de poliéster implantadas em aorta de coelhos através de fluoroscopia. Os objetivos do estudo foram: (1) analisar tubo de PDMS com reforço de poliéster implantado em aorta de coelhos como possível material para prótese vascular, (2) avaliar a patência das próteses através de fluoroscopia, (3) avaliar a condição de implante cirúrgico; (4) avaliar o comportamento macroscópico biológico do implante e (5) analisar o modelo experimental proposto. Próteses vasculares de PDMS foram implantadas na aorta infrarrenal de 64 coelhos cedidos pelo biotério da Faculdade de Medicina da Univesidade de São Paulo. Os exames de fluoroscopia foram realizados em até 150 dias após implantação cirúrgica. As próteses de PDMS foram classificadas em ocluídas e patentes, sendo essas sub-classificadas em diferentes graus de estenose. O tempo de clampeamento da aorta foi aferido durante os procedimentos cirúrgicos. De maneira amostral peças foram encaminhadas para microscopia eletrônica para verificação de endotelização das próteses. As análises estatísticas foram feitas através de teste t-Studant, teste ANOVA e Kaplan-Meier. Dos 64 animais que receberam a prótese, trinta (46,88%) apresentaram boa evolução clínica, vinte e três (35,94%) morreram e onze (17,18%) apresentaram paraplegia de membros posteriores. A patência das próteses em 30 dias foi de 87% (±6,7), em 60 dias foi de 73% (±9,3), em 90 dias foi de 57% (±11) e em 120 dias foi de 48% (±12). Cinquenta por cento (oito) das próteses patente não apresentaram nenhum grau de estenose, 35,5% (seis) apresentaram cinquenta por cento ou menos de estenose e 12,5% (dois) apresentaram estenose entre cinquenta e setenta por cento. Nenhum animal apresentou estenose maior que 70%. O tempo médio de clampeamento da aorta foi de 52 minutos. Não houve diferença significante nem na associação entre tempo de clampeamento da aorta e a evolução clínica dos animais (p=0,67) nem na associação entre o tempo de clampeamento e a patência das próteses (t=1,35; p=0,18). As peças encaminhadas para microscopia apresentaram crescimento endotelial a partir do vaso nativo em direção à prótese de PDMS. Foi possível concluir com este estudo que o PDMS demonstrou-se um material adequado para futuras pesquisas no ramo de próteses vasculares e que o uso da fluoroscopia na avaliação dessas próteses foi de fundamental importância na determinação da patência dos implantes / The present study evaluated small caliber vascular prostheses made of polydimethylsiloxane (PDMS) with polyester reinforcement implanted in the aorta of rabbits by fluoroscopy. The study objectives were: (1) analyze PDMS tube with polyester reinforcement implanted in the aorta of rabbits as possible material for vascular prosthesis, (2) assess the patency of the prosthesis through fluoroscopy, (3) assess the condition of surgical implant (4) evaluate the macroscopic behavior of biological implant and (5) analyze the proposed experimental model. Vascular prostheses were implanted in PDMS infrarenal aorta of 64 rabbits assigned by the animal house of the Faculty of Medicine of the University of São Paulo. Fluoroscopic examinations were performed within 150 days after surgical implantation. The prosthesis of PDMS were classified into occluded and patents, these being sub-classified into different degrees of stenosis. The time of aortic clamping was measured during surgical procedures. Sample pieces were sent for electron microscopy to check endothelialization of prostheses. Statistical analyzes were performed using t-test Studant, ANOVA and Kaplan-Meier. Of the 64 animals that received the prosthesis, thirty (46.88%) showed clinical improvement, twenty-three (35.94%) died and eleven (17.18%) had paraplegia of hind limbs. The patency of the prosthesis in 30 days was 87% (± 6.7), at 60 days was 73% (± 9.3), at 90 days was 57% (± 11) and at 120 days was 48 % (± 12). Fifty percent (eight) of the prosthesis patent did not present any degree of stenosis, 35.5% (six) had fifty percent or less of stenosis and 12.5% (two) had stenosis between fifty and seventy percent. No animal showed stenosis greater than 70%. The mean aortic clamping was 52 minutes. There was no significant difference in the association between duration of aortic clamping and clinical evolution of animals (p = 0.67) nor the association between clamping time and patency of the prosthesis (t = 1.35, p = 0.18). The parts sent for microscopy showed endothelial growth from the native vessel toward the prosthesis PDMS. It can be concluded from this study that the PDMS proved to be a suitable material for future research in the field of vascular prostheses and the use of fluoroscopy in the evaluation of these prostheses was of fundamental importance in determining the patency of the implants

Orientador: Guilherme Elias Pessanha Henriques / Tese (Doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-21T23:50:10Z (GMT). No. of bitstreams: 1 Torres_JoseWalterMurta_D.pdf: 1581851 bytes, checksum: 0bbcce2409164d19a4e51f955b38d595 (MD5) Previous issue date: 2013 / Resumo: Este trabalho avaliou a resistência ao destorque em parafusos de estruturas metálicas implanto-retidas fundidas em níquel-cromo (Ni-Cr) após fundição e simulação dos ciclos de cocção da porcelana. Dois implantes hexágono externo - com 3,75 mm de diâmetro - foram posicionados, com o auxílio de um paralelômetro fresador (1000N; Bio-art), na posição de segundo pré-molar e segundo molar num troquel de resina acrílica, de maneira a ficarem parcialmente submersos na resina expondo apenas suas plataformas de adaptação. Foram confeccionados 10 troqueis de resina acrílica (n=10). A partir de cada troquel foi obtida, pelo método de fundição da cera perdida, uma infraestrutura implanto-retida utilizando-se dois cilindros calcináveis tipo UCLA. A amostra foi submetida à força de torque de seus parafusos de fixação a 20 Ncm, registrada por meio de um torquímetro digital de precisão (Torque Meter TQ-8800; Lutron), e reapertados após 10 minutos. A força de destorque foi registrada após 24 horas do torque inicial. A resistência ao destorque foi analisada após fundição da estrutura protética e simulação dos três ciclos de cocção da porcelana (opaco dentina e glaze). Foram obtidas médias de destorque para cada estrutura nas distintas etapas de avaliação no estudo. Os dados foram analisados estatisticamente pelos testes ANOVA one-way e Bonferroni, com nível de significância de 5% (p<0,05). Os valores das médias da força de destorque dos parafusos por fase foram 13,95 ± 1,12 Ncm para pós-fundição, 15,20 ± 1,18 Ncm para ciclo Opaco, 15,85 ± 1,13 Ncm para ciclo Dentina e 16,80 ± 1,03 Ncm para o glaze. A força de destorque dos parafusos após a fundição foi significativamente menor do que a obtida para os grupos que simularam o ciclo de cocção da porcelana (p<0,05). Entre as fases de simulação dos ciclos cerâmicos, observou-se maior valor da força de destorque para o glaze (p<0,05), não sendo observadas diferenças estatisticamente significantes entre as fases opaco e dentina (p>0,05). Foi possível verificar que os ciclos de cocção da porcelana influenciam a resistência ao destorque em parafusos de estruturas metálicas implanto-retidas fundidas em níquel-cromo (Ni-Cr). Observou-se que os valores de destorque aumentaram gradativamente com cada ciclo de cocção da porcelana / Abstract: This study evaluated the resistance to detorque of screws from implant-retained metal structures cast in nickel-chromium (Ni-Cr) after metal casting and simulation of porcelain firing cycle. Two external hex implants - with 3.75 mm diameters - were placed with the help of a parallelometer cutter (1000N; Bio-art), in the position of second premolar and second molar in acrylic resin die, so as to be partially submerged in the resin exposing only their platforms for adaptation. Thereupon, 10 dies were made with acrylic resin (n= 10). An implant-retained infrastructure from each die was obtained by the method of lost wax casting, using two UCLA cylinders. The sample of acrylic structures were subjected to 20 Ncm of torque to its fixing screws registered by means of a precision digital torque wrench (Torque Meter TQ-8800; Lutron) and retightened after 10 minutes. The measure of detorque was recorded 24 hours after the initial torque. The detorque resistance was analyzed after denture casting, followed by the simulation of porcelain firing cycles (opaque, dentin and glaze). Detorque averages were obtained for each structure at different stages of evaluation in this study. Data was statistically analyzed by one-way ANOVA and Bonferroni tests, at 5% significance level (p>0.05). We performed necessary statistical tests. The mean detorque force of the screws per phase were 13.95 ± 1.12 Ncm for post-casting; 15.20 ± 1.18 Ncm for cycle opaque; 15.85 ± 1.13 Ncm for cycle dentin; and 16.80 ± 1.03 Ncm for glazing. The screw's post-casting detorque resistance was significantly lower than that observed for the groups simulating porcelain firing cycles (p<0.05). Among groups simulating ceramic's cycles, the highest detorque resistance was observed for glaze group (p<0.05), with no significant statistical differences among opaque and dentin groups (p>0.05). It was possible that the porcelain firing cycle influenced detorque resistance of screws in implant-retained metal structures cast in nickel-chromium (Ni-Cr). It was observed that detorque values gradually increased after each porcelain firing cycle / Doutorado / Protese Dental / Doutor em Clínica Odontológica

Le but de cette thèse était d'étudier, in vivo, la cinématique en 3D du genou lors de la marche sur des patients souffrant d'arthrose du genou et de quantifier l'apport de l'arthroplastie totale du genou (PTG) sur la restauration d'une cinématique normale. Trente patients et un groupe de contrôle composé de 12 participants du même âge ont été inclus dans la première étude. Sur ces 30 patients, nous avons obtenu des évaluations de suivi après l'arthroplastie totale du genou sur 20 patients, avec un délai moyen de 11 mois. L'analyse cinématique tridimensionnelle du genou a été réalisée en utilisant le système KneeKGTM. Cette analyse de la marche a révélé que la cinématique de genou avec arthrose médiale diffère de la cinématique du genou sain. Le groupe avec arthrose du genou montrait une stratégie de raidissement de la marche en présentant une réduction de mouvement non seulement dans le plan sagittal, mais aussi dans le plan axial. Après PTG, les patients avaient de meilleurs paramètres cliniques, spatio-temporels et cinématiques. Malgré les améliorations, la cinématique du genou lors de la marche dans le groupe PTG différaient de celle du groupe contrôle / Patients with knee osteoarthritis tend to modify spatial and temporal parameters during walking to reduce the pain. There are common gait features which are consistently shown to be significantly linked to osteoarthritis severity such as knee adduction moment, knee flexion angle, stiffness and walking speed. Total knee arthroplasty (TKA) is considered the gold standard treatment for end-stage knee osteoarthritis. Nearly a million of total knee prosthesis are implanted worldwide each year. However, reduced physical function of the knee is partly, but apparently not fully, remedied by surgery. The purpose of this thesis was to investigate the in vivo, three dimensional knee kinematics during gait at the patients with knee osteoarthritis and the influence of total knee arthroplasty on restoration of normal kinematics. Weight bearing kinematics in medial OA knees differ from normal knee kinematics. Knee OA group showed an altered “screw-home” mechanism by decreased excursion in sagittal and axial tibial rotation and a posterior translation of the tibia. Following TKA, patients had better clinical, spatiotemporal and kinametic parameters. They walked longer, faster and with a better range of motion. Despite improvements, the knee kinematics during gait in TKA group differed from healthy control group. They had a lower extension, lower range of axial rotation and an increased tibial posterior translation. Future research should be focused on comparing different designs of prosthesis pre- and post operatively in a longer follow-up delay

Ce travail de thèse avait comme objectif l'amélioration des outils de planning préopératoire tridimensionnels (P3D) pour l'arthroplastie totale de la hanche. Lors de l'utilisation d'implants sans ciment, une bonne stabilité primaire est requise pour obtenir une ostéointégration satisfaisante. Pour cela, une sélection appropriée de la taille et de la position de la prothèse est indispensable. En utilisant des images scanner obtenues par tomographie à rayon X de la hanche des patients, le chirurgien peut se servir du P3D pour faire la sélection de l'implant et anticiper sa position finale. Aujourd'hui, les méthodes de planning disponibles ne fournissent pas de critère mécanique qui pourrait refléter la qualité du contact os-implant. Nous proposons une méthode pour l'amélioration du P3D basé sur une analyse vibratoire par éléments finis pour le calcul de paramètres mécaniques personnalisés et liés á la stabilité primaire. Nos résultats suggèrent que la réponse modale de la tige est très sensible aux changements de l'aire de contact et de la raideur apparente de l'interface os-implant. Une transition marquée du comportement modal associée à un ancrage plus ou moins bon a permis de définir des seuils qui pourraient potentiellement discriminer des implants stables et instables dans le cadre du planning. Nous avons aussi étudié l'effet de la procédure de râpage et son possible impact sur le P3D. L'effet de la râpe sur la microstructure de l'os à l'interface os-implant a été analysé ex-vivo à l'aide d'images de micro-scanographie. Une distribution spatiale de la raideur de l'os en contact avec l’implant a aussi été obtenue par indentation des mêmes pièces anatomiques. / This thesis work is concerned with the enhancement of three-dimensional preoperative planning (P3D) tools for total hip reconstruction. When cementless implants are used, primary stability is vital for a good osseointegration. For this, a correct selection of the size and position of the implant is necessary. The surgeon may use P3D based on the computed tomography scanner of the patient’s hip to optimally select the implant’s size and anticipate the final implant’s position. Available planning methods lack a mechanical criterion reflecting the actual quality of the bone-implant contact. In this work we propose a method to improve P3D using a vibrational finite element analysis to calculate patient-specific mechanical parameters representative of primary stability. We found that the modal response of the stem is very sensitive to changes of the area and apparent stiffness of the bone-implant interface. A clear transition between loose and tight contact allowed the definition of thresholds that could potentially discriminate between a stable and an unstable stem. We also studied the effect of the broaching procedure and its relevance for P3D. The effect of broaching on bone microstructure at the bone-implant interface was analyzed using cadaveric samples and micro-computed tomography. A mapping of the stiffness of bone in contact with the implant was obtained with indentation on the same cadaveric samples.

Aux confluences historiques et conceptuelles de la modernité, de la technologie, et del’« humain », les textes de notre corpus négocient et interrogent de façon critique lespossibilités matérielles et symboliques de la prothèse, ses aspects phénoménologiques etspéculatifs : du côté subjectiviste et conceptualiste avec une philosophie de laconscience, avec Merleau-Ponty ; et de l’autre avec les épistémologues du corps ethistoriens de la connaissance Canguilhem et Foucault. Le trope prometteur de laprothèse impacte sur les formations discursives et non-discursives concernant lareconstruction des corps, là où la technologie devient le corrélat de l’identité. Latechnologie s’humanise au contact de l’homme, et, en révélant une hybridité supérieure,elle phagocyte l’humain du même coup.Ce travail d’anthropologie bioculturelle (Andrieu, 1993; Andrieu, 2006; Andrieu,2007a), au croisement d’une sociologie des sciences (Latour, 1989), ou encore d’uneanthropologie des sciences (Hakken, 2001), se propose en tant qu’exemple de lacontribution potentielle que l’anthropologie biologique et culturelle peut rendre à lamédecine reconstructrice et que la médecine reconstructrice peut rendre à la plastique del’homme ; l’anthropologie biologique nous concerne dans la transformation biologiquedu corps humain, par l’outil de la technologie, tant dans son histoire de la reconstructionmécanique et plastique, que dans son projet d’augmentation bionique. Nous établironsune continuité archéologique, d’une terminologie foucaldienne, entre les deux pratiques.Nous questionnons les postulats au sujet des relations nature/culture, biologie/contextesocial, et nous présentons une approche définitionnelle de la technologie, pierreangulaire de notre travail théorique. Le trope de la technologie, en tant qu’outil adaptatifde la culture au service de la nature, opère un glissement sémantique en se plaçant auservice d’une biologie à améliorer. Une des clés de notre recherche sur l’augmentationdes fonctions et de l’esthétique du corps humain réside dans la redéfinition même de cesrelations ; et dans l’impact de l’interpénétration entre réalité et imaginaire dans laconstruction de l’objet scientifique, dans la transformation du corps humain.Afin de cerner les enjeux du discours au sujet de l’« autoévolution » des corps, lesthéories évolutionnistes sont abordées, bien que ne représentant pas notre spécialité.Dans le cadre de l’autoévolution, et de l’augmentation bionique de l’homme, la7somation culturelle du corps s’exerce par l’usage des biotechnologies, en ruptureépistémologique de la pensée darwinienne, bien que l’acte d’hybridation évolutionnistesoit toujours inscrit dans un dessein de maximisation bionique/génétique du corpshumain. Nous explorons les courants de la pensée cybernétique dans leurs actions detransformation biologique du corps humain, de la performativité des mutilations. Ainsitechnologie et techniques apparaissent-elles indissociables de la science, et de sonconstructionnisme social. / Situated at the historical and conceptual crossroads of modernity, technology and the“human”, this thesis will negotiate and critique the material and symbolic possibilities ofthe prosthesis, together with its phenomenological and speculative aspects. This workwill be undertaken on the one hand from a subjectivist point of view, using Merleau-Ponty and his conceptualist philosophy of consciousness; and on the another from aviewpoint based on epistemologists of the body and historians of knowledge such asCanguilhem, and Foucault. The promising trope of the prosthesis has an impact ondiscursive and non-discursive structures related to the reconstruction of the body, wheretechnology becomes the correlate of identity.This work in Biological Anthropology (Andrieu, 1993, 2006, 2007), interwining withSociology of Sciences (Latour, 1989) and Anthropology of Sciences (Hakken, 2001), isproposed as an example of the potential contribution which biological and culturalanthropology can make to reconstructive medicine and which reconstructive medecinecan make to human corporeality ; Biological Anthropology allows us to study theprocess of the human body’s biological modification, via technology and theincorporation of biomaterial into the body, through the medical history of mechanicaland plastic reconstruction, and through the cybernetic project of bionic augmentation.An archeological continuity, to use Foucault’s terminology, will be established betweenboth practices.We will question the postulates at stake in the relationships between nature and culture,biology and social context, and will present as a cornerstone of our theoretical work awide range of definitional approaches. The trope of technology as an evolutionaryadaptative tool of culture in the service of nature allows a semantic slide whereby itbecomes a tool to improve one’s biology. One of the keys of our research into thetransformation of the human body in medical practices is the very redefinition of thoserelationships; another is the impact of the interpenetration of reality and imaginary in theconstruction of the scientific object and the transformation of the human body.8In order to locate what is at stake in the discourse on “auto-evolution”, evolutionarytheories are tackled, albeit from a non-specialist outlook. In the context of autoevolutionand bionic augmentation of the human, the cultural somatic modification ofthe body

BAKGRUND: Personer med amputation på transhumeral nivå har en asymmetrisk anatomi. Det är inte väl studerat hur denna asymmetri påverkar dessa personers stående och gång, och inte heller vilka besvär som detta skulle kunna orsaka. SYFTE: Att undersöka om någon skillnad i stillastående kropps-hållning och gångmönster uppstår då personer med transhumeral amputation använder respektive inte använder protes. Utöver det så är också syftet att undersöka om ryggbesvär förekommer hos personer med denna amputationsnivå. METOD: Två transhumeralt amputerade personer deltog i studien. Statisk undersökning och gånganalys genomfördes med och utan armprotes. En enkätundersökning gällande muskuloskeletala besvär genomfördes på deltagarna. RESULTAT: Inga större skillnader har hittats i bäckenets kinematik och bålens rörelse i sagittalplan då försökspersonerna går utan protes jämfört med när de går med protes. Däremot har vi funnit en thorakal lateralflexion mot den amputerade sidan under gång, som minskar då försökspersonerna använder protes. Då försökspersonerna är stillastående utan protes lutar de mot den amputerade sidan. När de använder protes minskar lutningen. Försökspersonerna led inte av ryggbesvär. SLUTSATS: Användande av armprotes för personer med transhumeral amputation verkar ge en rakare hållning under gång och stående. / BACKGROUND: People with transhumeral amputation have an asymmetrical anatomy. The influence of this asymmetry on gait and standing has not been well studied, neither has the potential problems that this could cause. OBJECTIVE: To investigate if any difference in standing posture and gait kinematics occur when people with transhumeral amputation use a prosthesis compared to when they don’t. Furthermore, the aim is to investigate if back problems are prevalent among people with this amputation level. METHODS: Two transhumeral amputees participated in this study. Static and gait analysis was conducted with and without prosthesis. The participants completed a survey regarding musculoskeletal problems. RESULTS: No major difference has been found in thorax tilt and pelvic kinematics when the subjects walk with compared to without prosthesis. However we have found a thorax obliquity towards the amputated side during walking, which is reduced when the subjects use their prosthesis. The subjects are leaning towards the amputated side when standing without prosthesis. When using the prosthesis the obliquity is reduced. The subjects do not suffer from any back problems. CONCLUSIONS: Use of an arm prosthesis seems to give people with transhumeral amputation a more upright posture during walking and standing.

Objetivo: Avaliar o desajuste vertical (gap) e discrepância horizontal (dh) na interface implante/pilares de zircônia (Zr) confeccionados por três sistemas CAD/CAM (Neodent Digital, Zirkonzahn e AmannGirrbach) e na interface implante de titânio/pilar de ZrTi confeccionado pela Neodent Digital, antes e após ciclagem mecânica. Também foi avaliada a superfície do hexágono do implante antes e após ciclagem mecânica e o destorque do parafuso do pilar pós-ciclagem. Método: Os grupos de estudo constituídos por oito amostras foram: implante/pilar de Zr AmannGirrbach (PZrAG), implante/pilar de Zr Neodent (PZrN), implante/pilar de Zr Zirkonzahn (PZrZ) e implante/pilar de Zr com infra-estrutura em Ti Neodent (PZrTiN). Pilares padronizados foram confeccionados a partir de três pilares idênticos fresados em cera, fixados sobre análogos e enviados para os laboratórios participantes do estudo. A análise da superfície, do gap e da dh foram realizadas em três amostras de cada grupo e o destorque em oito. Inicialmente, imagens da superfície dos hexágonos dos implantes foram obtidas em Microscópio Eletrônico de Varredura (MEV). Em seguida, imagens das superfícies dos pilares foram obtidas com microscópio óptico 3D (MO 3D) e posteriormente, os pilares foram acoplados aos implantes com torque de 32,0N.cm. Subsequentemente, imagens das interfaces implante/pilar foram obtidas em MEV para posterior comparação com as imagens pós-ciclagem. Coroas de CrCo foram cimentadas nos pilares e os conjuntos (implante/pilar/coroa) submetidos à ciclagem com carga de 400N, frequência de 8,0 Hz, por um milhão de ciclos. Novas imagens da interface implante/pilar foram obtidas em MEV e realizadas as medições inicial e final do gap e a avaliação da dh. Em seguida, foi mensurado o destorque. Para a avaliação da superfície dos implantes, novas imagens foram obtidas em MEV e comparadas com a situação inicial. As alterações verificadas foram classificadas segundo os escores: ausência(0), leve(1), moderada(2), intensa(3). Resultados: Para o destorque(N.cm) nos grupos de Zr, o PZrZ apresentou o maior valor médio 23,12(2,7), seguido pelo PZrAG 19,57(4,3) e PZrN 19,43(1,9). O valor aferido para o grupo PZrTiN foi 21,0(2,5). Com relação às alterações de superfície, entre os grupos de Zr, a maior alteração foi observada no PZrZ 1,39(0,99) e a menor no PZrAG 0,64(0,62). O PZrTiN apresentou o seguinte valor: 0,53(0,56). Com relação ao gap, entre os grupos de Zr, o maior valor médio foi evidenciado no PZrAG 5,19(2,07)&#956;m e o menor no PZrN 3,21(1,47)&#956;m. O grupo PZrTiN 1,48(1,04)&#956;m apresentou valor inferior ao grupo PZrN. Entre os pilares de Zr, o maior valor de dh foi observado no PZrAG 49,98(9,06)&#956;m e o menor no PZrZ 31,53(32,33)&#956;m. O PZrTiN não apresentou dh. Conclusões: Com relação ao destorque, não foi observada diferença significativa entre os grupos de zircônia, assim como entre os grupos da Neodent (Zr e ZrTi). Entre os pilares de Zr, as maiores alterações de superfície do hexágono foram observadas no grupo PZrZ e entre os pilares fresados pela Neodent (Zr e ZrTi) no PZrN. Foi observado que as alterações de superfície mantiveram relação com a forma do hexágono fresado no pilar. Quanto ao gap, entre os pilares de Zr, não foi observada diferença significativa entre os grupos; entre os pilares da Neodent (Zr e ZrTi), antes e pós ciclagem, diferença significativa foi observada entre os dois grupos, apenas antes da ciclagem; quando avaliado o gap de cada grupo antes e após a ciclagem mecânica, só o PZrZ mostrou diferença significativa. Os grupos PZrAG e PZrZ apresentaram maiores valores de gap pré-ciclagem quando considerados por face e na situação pós-ciclagem os pilares sofreram inclinação sobre o implante. Com relação à dh, quando considerados os grupos em Zr, o menor valor médio foi verificado no PZrZ e o PZrN apresentou maior regularidade entre os quatro lados observados. Todos os pilares de Zr apresentaram discrepância horizontal, alternando graus diferentes de sobre-contorno numa mesma amostra. / Purpose: To evaluate the vertical misfit (gap) and horizontal discrepancy (dh) in the zirconium (Zr) implant-abutment interface manufactured by three CAD/CAM systems (Neodent Digital, Zirkonzahn and AmannGirrbach) and the ZrTi implant-abutment manufactured by Neodent, before and after cyclic loading. The surface of the titanium (Ti) hexagon implant was also evaluated before and after cyclic loading as well as the torque loss of the abutment screw post loading. Method: The study groups made up of 8 samples were as follows: Zr AmannGirrbach (PZrAG) implant-abutment, Zr Neodent (PZrN) implant-abutment, Zr Zirkonzhan (PZrZ) implant-abutment and Zr implant-abutment with Ti Neodent (PZrTiN) infrastructure. Standard-made abutments were manufactured from three identical abutments milled in wax, fixed on analogs and sent to the participant laboratories. The analysis of the surface, the gap and the dh were performed on three samples from each group and the torque loss was performed on eight samples. Initially, images of the surface of the hexagon implant were obtained by Scanning Electron Microscope (SEM). Then, images from the abutment surfaces were obtained from optical microscope 3D (MO 3D), followed by the tightening of the abutments to the implants with torque of 32.0N.cm. Subsequently, images of the implant-abutment interfaces were obtained from the SEM for comparison with the post loading images. CrCo crowns were cemented on the abutments and the combination (implant/abutment/crown) was submitted to cyclic loading with a load of 400N, frequency of 8.0Hz, for one million cycles. New images of the implant-abutment interface were obtained from the SEM, and initial and final gap measurements were done with evaluation of the dh. The torque loss was measured. For the evaluation of the surface of the implants, new images were obtained from the SEM and compared with the initial situation. The observed changes were classified according to the following categories: none (0), mild (1), moderate (2), intense (3). Results: In relation to the torque loss (N.cm) in the groups of Zr, the PZrZ showed the highest average of 23.12(2.7), followed by the PZrAG of 19.57(4.3) and the PZrN of 19.43(1.9). The measured value for the PZrTiN was 21.0(2.5). In regards to the surface alterations among the Zr groups, the highest change was observed in the PZrZ of 1.3 9(0.99) and the lowest change in the PZrAG of 0.64(0.62). The PZrTiN group presented the following value: 0.53(0.56). In regards to the gap among the Zr groups, the highest average value was evidenced in the PZrAG of 5.19(2.07)&#956;m and the lowest in the PZrN of 3.21(1.47)&#956;m. The PZrTiN group of 1.48(1.04)&#956;m showed an inferior value compared to the PZrN group. Among the Zr abutments, the highest horizontal discrepancy value was observed in the PZrAG of 49.98(9.06) and the lowest value was observed in the PZrZ of 31.53(32.33)&#956;m. The PZrTiN did not present dh. Conclusions: Regarding torque loss, significant differences were not observed among the zirconium groups, as well as among the Neodent groups (Zr and ZrTi). Among the Zr abutments, the largest hexagon surface alterations were observed in the PZrZ group and among the abutments milled by Neodent (Zr and ZrTi) in the PZrN. It was observed that surface changes showed that a relationship is maintained with the shape of the hexagon milled in the abutment. As to the gap among the Zr abutments, no significant difference was noted among the groups; between the Neodent abutments (Zr and ZrTi), before and after cyclic loading significant difference between the two groups was observed only before cyclic loading. When evaluated the gap of each group before and after cyclic loading, only the PZrZ showed significant difference. The groups PZrAG, and the PZrZ showed the highest pre-cycling gap when considered by face-value and in the post loading situation, the abutments suffered inclinations over the implant. As to dh when considering the Zr groups, the lowest average value was found in the PZrZ, and the PZrN showed highest regularity among the four sides observed. All Zr abutments showed horizontal discrepancy alternating different levels of over-contour in the same sample.

O objetivo deste estudo foi avaliar o assentamento passivo de supra-estruturas de próteses fixas implanto-suportadas de três elementos, fundidas em titânio comercialmente puro e em ligas à base de Ni-Cr e Co-Cr. Para esta análise foi utilizado o método de Sheffield (EISENMAN, 1997), e as leituras foram realizadas num microscópio óptico comparador (Nikon, Japão). Foram utilizados dois implantes de hexágono interno Master Conect AR (Conexão Sistemas de Prótese, Brasil). Os dados foram submetidos à análise de variância (ANOVA) e também ao teste complementar de Tukey-Kramer. A análise dos dados permitiu concluir que: as interfaces, quando os três grupos foram analisados em monobloco e com os dois parafusos apertados, foram mais satisfatórias para o grupo fundido em liga de Ni-Cr (25,00 ± 7,92&#956;m), apesar deste grupo não ser estatisticamente diferente dos outros dois (Co-Cr: 54,23 ± 37,10&#956;m e Ti cp: 48,41 ± 26,69&#956;m). No teste do parafuso único os três grupos também foram estatisticamente iguais, com os seguintes resultados, no lado parafusado: Co-Cr: 35,01 ± 27,76&#956;m, Ni-Cr: 20,13 ± 7,97&#956;m, e Ti cp: 22,28 ± 17,29&#956;m, e no lado contrário: Co-Cr: 118,64 ± 91,48&#956;m, Ni-Cr: 70,66 ± 20,88&#956;m, e Ti cp: 118,56 ± 51,35&#956;m. Neste mesmo estudo também se realizou a secção das peças e posterior soldagem a laser. A soldagem foi conduzida na máquina Desktop Laser (Dentaurum, Alemanha). A análise do assentamento passivo foi novamente realizada pelo método de Sheffield e as leituras foram feitas no microscópio óptico comparador (Nikon). O procedimento de separação das peças em monobloco e posterior soldagem a laser resultou em diminuição estatisticamente significante nos níveis de desajuste quando analisadas as peças com os dois parafusos apertados para o grupo fundido em liga de Co-Cr (21,49 ± 9,08&#956;m). Para os outros dois grupos, liga de Ni-Cr (13,10 ± 1,81&#956;m) e Ti cp (17,70 ± 11,70&#956;m), os resultados não apresentaram diferenças estatisticamente significantes, apesar de apresentarem menores níveis de desajuste marginal. No teste do parafuso único e leitura no lado oposto, apenas o grupo fundido em liga de Ni-Cr (19,81 ± 7,36&#956;m) não apresentou diferença estatisticamente significante quando comparado à fundição em monobloco. Os grupos em liga de Co-Cr (41,02 ± 26,15&#956;m) e em Ti cp (40,42 ± 27,14&#956;m) apresentaram diferenças estatisticamente significantes após a soldagem a laser. Na leitura no lado apertado os três grupos foram estatisticamente iguais. A simulação dos ciclos de queima da cerâmica não provocou alterações significativas nas interfaces analisadas sob todas as condições de leitura e aperto dos parafusos. Os grupos fundidos em ligas de Co-Cr e em Ti cp, quando analisados com apenas um parafuso apertado e as leituras realizadas no lado oposto, apresentaram diminuição dos níveis de ajuste, sendo 26,42 ± 8,67&#956;m, após a simulação, quando era 41,02 ± 26,15&#956;m após soldagem a laser para o primeiro e, 40,42 ± 27,14&#956;m e 28,05 ± 20,89&#956;m, antes e após a simulação, para o segundo, porém sem diferenças estatisticamente significantes. / The purpose of this study was to evaluate the precision of fit of three-element implant-retained and supported frameworks, cast in Ni-Cr- and Co-Cr alloys and commercially pure titanium (Cp Ti). The Sheffield´s test (EISENMAN, 1997) was used to analyze the marginal interfaces, and the readings executed in an optic microscope (Nikon, Japan). Two Master Conect AR (Conexão Sistemas de Prótese, Brazil) internal-hexagon implant systems were used. Data were submitted to analysis of variance (ANOVA) with complementary Tukey-Kramer’s test. Data analysis showed that: the interfaces, when analyzed as a one-piece casting and with both screws tightened, were better for the group cast in Ni-Cr alloy (25.00 ± 7.92&#956;m), though not statistically different from the two other groups (Co-Cr: 54.23 ± 37.10&#956;m e Cp Ti: 48.41 ± 26.69&#956;m). In the single screw tightened test the three groups showed no statistical difference, with the following results, on the tightened side: Co-Cr: 35.01 ± 27.76&#956;m, Ni-Cr: 20.13 ± 7.97&#956;m, and Cp Ti: 22.28 ± 17.29&#956;m, and on the opposite side: Co-Cr: 118.64 ± 91.48&#956;m, Ni-Cr: 70.66 ± 20.88&#956;m, and Cp Ti: 118.56 ± 51.35&#956;m. On this same study, the one-piece castings were sectioned and laser welded. The laser welding was executed with the Desktop Laser (Dentaurum, Germany) machine. The Sheffield´s test was used to analyze the passive fit, and the readings executed in an optic microscope (Nikon). The procedure of sectioning the one-piece castings and its later laser welding presented statistically significant lower levels of misfit when the castings were analyzed with both screws tightened for the group cast in Co-Cr alloy (21.49 ± 9.08&#956;m). For the other two groups, Ni-Cr alloy (13.10 ± 1.81&#956;m) and Cp Ti (17.70 ± 11.70&#956;m), results presented no statistically significant differences, though showed lower levels of marginal fit. In the single screw tightened test and readings made on the opposite side, only the group cast on Ni-Cr alloy (19.81 ± 7.36&#956;m) didn’t present statistically significant lower levels of misfit when compared to single-piece castings. The Co-Cr alloy (41.02 ± 26.15&#956;m) and the Cp Ti (40.42 ± 27.14&#956;m) groups showed statistically significant differences after laser welding. The reading on the screwed side detected that the three groups were statistically the same. Simulation of the porcelain firing cycles did not develop any significant differences on the analyzed interfaces under all readings and screw tightening conditions. The groups cast in Co-Cr alloy and Cp Ti, when analyzed with only one screw tightened and the readings executed on the opposite side, presented lower levels of misfit, being 26.42 ± 8.67&#956;m, after simulation, when was 41.02 ± 26.15&#956;m after laser welding for the first and, 40.42 ± 27.14&#956;m and 28.05 ± 20.89&#956;m, before and after, for the second, though not showing any statistically significant differences.

Ce travail se situe dans le cadre d'un projet pluridisciplinaire visant à développer une prothèse visuelle. La technique la plus utilisée actuellement dans de nombreux types de neuroprothèses est basée sur l'excitation par voie électrique via des électrdes. Les inconvénients d'une telle technique (très invasive, de faible résolution spatiale et par contact) pourraient être surmontés en utilisant une stimulation par laser infra-rouge. Nous présentons dans un premier temps les caractéristiques des trois diodes lasers fibrés émettant à 1875 nm, 1535 nm et 1470 nm pour des gammes de puissances optiques de quelques centaines de mW qui ont été utilisés et intégrés à deux dispositifs de mesures permettant l'observations de variations d'échanges ioniques transmembranaires (imagerie de fluorescence des ions calciums et mesure électrophysiologique par la technique de patch clamp). Nous montrons ensuite que des réponses biologiques ont été obtenues par les trois lasers, non seulement sur des cellules ganglionnaires de la rétine et du vestibule de culture mais aussi sur des tranches de rétine. L'influence des paramètres clés comme la longueur d'onde, la durée de stimulation, les seuils d'énergie a été étudié, et a permis d'établir que les seuils d'énergie de stimulation dépendent de la valeur du coefficient d'absorption de l'eau qui varie suivant la longueur d'onde utilisée. Enfin, une étude est consacrée pour expliquer les mécanismes physiques et biologiques apparaissant au cours de l'interaction du laser avec le neurone au niveau cellulaire. Des simulations numériques quantifiant l'élévation de température associées à des tests pharmacologiques cherchant à déterminer la nature des canaux ioniques spécifiques mis en jeu suggèrent la prédominance d'un effet thermique. / This work is part of a pluridisciplinary project, aiming at developing a visual prosthesis. The most used technique for this kind of neuroprosthesis is based on the electrical stimulation of nerves by electrodes. Drawbacks of such a technique (very intrusive, low spatial resolution and physical contact) could be overcome by the use of an infra red laser based stimulation. We present first the three fibre pigtailed laser diode characteristics emitting few hundred of mW at 1875 nm, 1535 nm and 1470 nm. These lasers have been integrated on two measurement devices (a fluorescence microscope and a microscope using patch clamp recording), for the observation of ionic membrane exchanges. Our results show that action potentials have been obtained by laser stimulation from the three lasers, both on retinal or vestibular ganglion cells from mass cultures and on retinal slices. The effect of key parameters as the wavelength, the stimulation time, the energy thresholds has been studied and show that the energy thresholds clearly depend on the absorption coefficient of water which varies with the wavelength. Finally, we present the results of a preliminary study aiming at determining the biophysical interaction mechanisms at cell level. Numerical simulations giving the local increase of temperature and tests of specific blocking molecules in order to know the exact nature of the ionic channels involved suggest a predominant thermal mechanism.