Dissertations / Theses: 'Osseointegration implant'

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Sjostrom, Terje. "Nanopatterning of titanium surfaces for improved implant osseointegration." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503860.

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With increasingly higher performance requirements and health care costs associated with dental and orthopaedic bone-anchored implants there is a need to improve the osseointegration of Ti implants. Small alterations in nanotopography feature dimensions and arrangement has recently been shown able to differentiate human mesenchymal stem cells into an osteoblastic lineage, thus showing potential for using nanotopography to improve osseointegration of Ti implants.

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Shao, Fei. "Natural frequency analysis for osseointegration trans-femoral implant." Thesis, University of Surrey, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443397.

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Mirza, Rizwan. "Customized Biomimetic Coatings for Hip and Spinal Implants to Reduce Implant-Related Infections and Promote Osseointegration." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1291215710.

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Omoniala, Kennedy. "Surface modification strategies for antimicrobial titanium implant materials with enhanced osseointegration." Thesis, De Montfort University, 2016. http://hdl.handle.net/2086/14462.

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The use of exogenous materials to replace or repair dysfunctional tissues and organs has seen dramatic improvements since the time of the ‘physician-hero’. The past three decades have heralded the advancement of various materials and technologies for medical implant devices to repair, replace or regenerate irreversibly damaged tissues. Improvement in health outcomes, evident in life expectancy increase, has brought in its wake the increased need to replace or repair tissues, particularly weight-bearing bone tissues. Titanium (Ti), a non-magnetic, corrosion resistant, osseo-integrating metal, with a higher strength-to-weight ratio than the traditional stainless steel, has emerged as the material of choice for replacing bone and other support tissues. However, the quest for improved performance (osseointegration) and reduction in implant related infection resulting in the need for resection surgeries, has necessitated the need to improve the titanium-tissue interface mediated osseointegration process, and confer antimicrobial properties to the implant material surface. In this work, a simple cost effective physical and chemical modification strategies have been developed, to alter the surface chemistry, increase the surface water wettability and confer a nano topographic characteristic to the Ti surface. These surface parameters have been demonstrated to enhance the osseointegration process. The chemical treatments resulted in oxides containing the following ions: Calcium (Ca), for improvement of osteogenic cell adhesion to Ti surface, Silver (Ag), and Zinc (Zn) for conferring antimicrobial properties to the novel surface, and their composites (CaAg, CaZn and CaZnAg), Scanning electron microscope (SEM) profiles of the modified surface suggest that, ions are chemically bound and not physically deposited onto the Ti surface. Further evidence of this is provided by the release profile of these elements from the modified surface over a 28-day period. We have also demonstrated that, the physically modified Ti surface is better at incorporating our elements of interest than the commercially pure titanium (cpTi) surface. xi The results from a Staphylococcus aureus biofilm formation assay, and U2OS bone cell adhesion and proliferation studies, suggest that, the physical modifications enhanced both the antimicrobial performance and the osteoblast-like cell adhesion and proliferation. The suggestion also is that, the incorporated Ca further enhances the adhesion and proliferation of bone-like cells, whereas Zn and markedly Ag improve the modified Ti surface’s antimicrobial properties. However, Ag alone has been shown to have a toxic effect on the bone cells; a promising combination treatment involving Ca, Zn and Ag appears to have beneficial response in all tests.

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Du, Zhibin. "The effects of osteoporosis on osseointegration in the rat maxilla." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/87977/1/Zhibin_Du_Thesis.pdf.

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The study investigated the effects of oestrogen deficiency on dental implant in a rat model. An osteoporosis rat model was successfully established for dental implant research and it was noted that bone cells functioned differently in osteoporotic condition during the healing of dental implant. The study further demonstrated that implant surface roughness could stimulate bone formation, therefore, improve the bone healing in osteoporotic condition.

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Dorce, Cristiane Marques. "Avaliação de dispositivo para viabilização de análise de frequência de ressonância em implantes dentários em ovelhas." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/25/25146/tde-31082018-171426/.

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Afirmação do problema. Estudos experimentais em animais são utilizados para avaliar previamente o resultado de pesquisas e sua necessidade de serem realizadas em humanos. Estudos em animais são fundamentais na implantodontia para que haja uma melhor compreensão da osseointegração. Durante o processo de execução de pesquisas nesse tipo de estudo, algumas dificuldades relacionadas ao manuseio, custos de manutenção e bem-estar dos animais tendem a dificultar o seu desenvolvimento. Finalidade. Esse estudo tem como objetivo, testar um novo dispositivo acoplado sobre o implante, para que possa atuar como uma extensão do mesmo, facilitando a realização da Análise de Frequência de Ressonância durante o processo de osseointegração permitindo que implantes instalados em ovelhas em diferentes períodos, possam ser reabertos sem que haja a necessidade de etapas cirúrgicas para a reabertura durante a realização de testes. Material e métodos. Foram utilizadas 4 ovelhas, sendo uma do Grupo Controle (GC) e 3 do Grupo Teste (GT). Cada animal recebeu oito implantes localizados próximos ao ângulo da mandíbula, sendo quatro do lado esquerdo e quatro do lado direito, totalizando, 32 implantes cone-morse Acqua® de 3,5 de diâmetro por 8,5mm de comprimento da empresa Neodent® que foram avaliados pela análise de frequência de ressonância com a medição do ISQ (Quociente de Estabilidade do Implante) utilizando um transdutor (SmartPeg) expressos numa escala de 0 a 100. Para o Grupo Controle (GC) as medições de ISQ foram realizadas pelo método convencional, onde o SmartPeg foi acoplado diretamente sobre a plataforma do implante. Já no Grupo Teste (GT) o dispositivo estudado, foi acoplado ao implante para que pudesse ser realizada a medição. Os períodos estudados foram: imediatamente após a cirurgia e com quatro semanas de osseointegração. Para a análise estatística foram empregados os testes de Wilcoxon e Man-Whitney com a probabilidade de 5% (p<0.05). Resultados. As médias obtidas no GC foram 50,47 imediatamente após cirurgia e 65,68 após 4 semana, enquanto que no GT foram 34,74 e 34,81, respectivamente. Comparando a diferença entre os grupos nas médias de ISQ imediatas e após quatro semanas, houve diferença significativa com p= 0.0321 e p= 0.0027, respectivamente, demonstrando que os resultados no GT nos dois períodos não foram equivalentes quando comparados ao GC. Conclusão. Os resultados demonstraram que o grupo teste, apesar de trazer benefícios em relação ao manuseio dos animais, não apresentou benefícios com relação à eficiência na leitura do ISQ, quando comparado ao método convencional.
Statement of the problem. Experimental studies in animals are used to pre-evaluate the results of research and their need to be performed in humans. Animal studies are fundamental in implantology so that there is a better understanding of osseointegration. During the execution of research in this type of study, some difficulties related to handling, maintenance costs and animal welfare tend to hinder its development. Purpose. This study aims to test a new device coupled on the implant, so that it can act as an extension of the same, facilitating the performance of the Resonance Frequency Analysis during the osseointegration process allowing implants installed in different periods of time, can be reopened without the need for surgical steps for reopening during testing. Material and methods. Four sheep were used, one being from the Control Group (GC) and 3 from the Test Group (GT). Each animal received eight implants located near the angle of the mandible, four on the left side and four on the right side, totaling 32 Acqua® 3.5 mm diameter 8.5 mm long implants of the company Neodent® that were evaluated by the resonance frequency analysis with the ISQ (Implant Stability Ratio) measurement using a transducer (SmartPeg) expressed on a scale of 0 to 100. For the Control Group (GC) the ISQ measurements were performed by the conventional method, where the SmartPeg was attached directly onto the implant platform. In the Test Group (GT) the studied device was attached to the implant so that the measurement could be performed. The periods studied were: immediately after surgery and four weeks of osseointegration. For the statistical analysis Wilcoxon and Man-Whitney tests were used, with a probability of 5% (p <0.05). Results. The averages obtained in the CG were 50.47 immediately after surgery and 65.68 after 4 weeks, while in the GT were 34.74 and 34.81, respectively. Comparing the difference between the groups in the means of immediate SAI and after four weeks, there was a significant difference with p = 0.0321 and p = 0.0027, respectively, demonstrating that the results in the WG in the two periods were not equivalent when compared to the CG. Conclusion. The results showed that the test group, despite having benefits in relation to the handling of the animals, did not present benefits in relation to the efficiency of the ISQ reading when compared to the conventional method.

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Souza, Edmo Matheus Rocha de. "Influência da zircônia no arrefecimento de brocas para implantes osseointegráveis: ensaio mecânico." Universidade Federal de Sergipe, 2015. https://ri.ufs.br/handle/riufs/5895.

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Specimens were made from bovine ribs and milling divided into two groups (A - B mills in steel - mills in zirconia), each group was divided into four subgroups according to different settings milling (rotation and pressure milling). They were measured and compared the temperatures of the milling burs made by the two materials made using four different configurations. A prosthetic surveyor has been adapted to the study to connect a surgical electronic engine, counter angle driver for implants. A container was also coupled to one of the liner's arms to accommodate components metallic spheres of standard weight, sometimes 1.2kg, 2.4kg moment according to the configuration of each subgroup such that the surgical motor that ran milling in 1000 and 2000 rpm. In order to measure milling temperatures, they used two thermocouples of the same make and model in two depths milling, the first and the second 5mm to 15mm. All the cutters are subjected to washing and antisepsis every two tests. The heat generated by the friction between bone and surgical instrumentation during such drills tend to be imparted to this tissue degeneration resulting protein that cause scarring and can be decisive in higher failure rates. Several factors are potentially destined to contribute to increasing the temperature for the osteotomies of which insufficient irrigation, using worn drills, surgical instrumentation outside the standard suggested by the manufacturer and the material constituting the object of this study surgical drills.
Corpos de prova foram confeccionados a partir de costela bovina e as fresagens divididas em dois grupos (A – fresas em aço martensíntico e B – fresas em zircônia), cada grupo foi subdividido em quatro subgrupos de acordo com configurações diferentes de fresagem (rotação e pressão de fresagem). Foram aferidas e comparadas as temperaturas das fresagens realizadas por brocas confeccionadas nos dois materiais através de quatro configurações diferentes. Um delineador protético foi adaptado ao estudo para conectar-se um motor eletrônico cirúrgico, propulsor de contra ângulo para implantes. Um recipiente também foi acoplado a um dos braços do delineador para que acomodasse esferas metálicas componentes do peso padrão, ora 1,2kg, ora 2,4kg de acordo com a configuração de cada subgrupo tal qual o motor cirúrgico que executava fresagens em frequências de 1000 e 2000 rpm . Para mensuração das temperaturas de fresagem, foram utilizados dois termopares da mesma marca e modelo em duas profundidades de fresagem, a primeira a 5mm e a segunda a 15mm. Todas as fresas foram submetidas à lavagem e degermação a cada dois testes. O calor gerado através da fricção entre osso e brocas durante essas instrumentações cirúrgicas tende a ser transmitido a este tecido provocando degeneração proteica que acarretam cicatrizes e podem ser determinantes para taxas de insucesso mais altas. Diversos fatores estão potencialmente predestinados a contribuir com o aumento da temperatura durante as osteotomias dentre os quais, irrigação insuficiente, utilização de brocas desgastadas, instrumentação cirúrgica fora do padrão sugerido pelos fabricantes e material constituinte das brocas cirúrgicas-objeto desse estudo.

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Selecman, Audrey Marie. "Evaluation of osseointegration between two different modalities of hydroxyapatite implant surface coatings plasma sprayed HA coated implants and electrophoresis deposited nano HA coated implants /." View the abstract Download the full-text PDF version, 2007. http://etd.utmem.edu/ABSTRACTS/2007-008-Selecman-index.html.

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Thesis (M.S. )--University of Tennessee Health Science Center, 2007.
Title from title page screen (June 30, 2008). Research advisor: Joo L. Ong, Ph.D. Document formatted into pages (vi, 47 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 41-46).

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Barbara, Mary Anne Moreira [UNESP]. "Influência da Superfície do implante e da laserterapia na osseointegração, em ratas osteopênicas." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/95864.

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Com o aumento da expectativa de vida da população é importante o estudo de tratamentos alternativos e de biomateriais que visam auxiliar no processo de osseointegração em pessoas com osteoporose. O presente estudo avaliou e comparou a osseointegração de implantes cilíndricos de superfície porosa com implantes cilíndricos de superfície rugosa, ambos de titânio, em ratas osteopênicas e normais, por meio de análise histológica e histomorfométrica. Avaliou também a influência do tratamento com laser de baixa potência (Arseneto de Gálio Alumínio) sobre a osseointegração. Os implantes foram inseridos em 84 ratas, cada rata recebeu um implante poroso no fêmur esquerdo e um implante rugoso no direito. Quarenta e dois dos animais foram submetidos à cirurgia de ovariectomia (OVZ) e 42 foram falsamente operados (SHAM). Após um mês, as ratas foram divididas em 4 grupos, com 21 animais cada, de acordo com o tratamento recebido: a) grupo 1 (SHAM): cirurgia de colocação dos implantes (CI); b) grupo 2 (SHAM): CI e aplicação do laser de baixa potência (LLLT); c) grupo 3 (OVZ): CI; d) grupo 4 (OVZ): CI e LLLT. Sete animais de cada grupo, selecionados aleatoriamente, foram sacrificados 2, 4 e 6 semanas após a cirurgia, os fêmures contendo os implantes foram submetidos à análise histológica e histomorfométrica. Na análise histológica observou-se que houve osseointegração em ambos implantes nos diferentes grupos. Após avaliação da análise histomorfométrica verificou-se que o grupo 4, os implantes do tipo poroso, com animais sacrificados 4 semanas após a cirurgia de implante exibiu maior porcentagem de neoformação óssea, seguido do grupo 2, com implante poroso 4 e 6 semanas de período de sacrifício. Concluiu-se que a laserterapia melhora significantemente a neoformação óssea e que os implantes de superfície porosa apresentam maior área para contato na interface osso-implante.
With increasing life expectancy of the population is important to the study of alternative treatments and biomaterials which aim to assist in the process of osseointegration in people with osteoporosis. .This study involved an assessment and comparison of the osseointegration of cylindrical titanium implants with porous surfaces and with rough surfaces in osteopenic rats, based histological and histomorphometric analyses. An evaluation was also made of the influence of low level laser therapy (LLLT) with gallium-aluminum arsenate (Ga-Al-As) on osseointegration. The implants were placed in 84 rats, two per rat, i.e., a porous implant in the left femur and a rough implant in the right femur Forty-two of the animals were then ovariectomized (OVZ) while the other 42 were subjected to a sham ovariectomy (SHAM). After one month the rats were divided randomly into four groups of 21 animals each, according to treatment received: a) group 1 (SHAM) implant surgery (IS); b) group 2 (SHAM) IS and low-level laser therapy (LLLT); c) group 3 (OVZ): IS; d) group 4 (OVZ) IS and LLLT. Seven animals from each group were selected randomly and killed 2, 4 and 6 weeks after surgery and the histomorphometric analyses. The histological analysis revealed that osseointegration occurred in both types of implants in all the groups. The histomorphometric analysis indicated that the porous implants in the group 4, killed 4 weeks after implantation, showed the highest percentage of new bone formation, followed by the porous implants in group 2, killed 4 and 6 weeks after implantation. It was concluded that laser therapy significantly improves new bone formation and that implants with porous surfaces have a larger contact area at the bone-implant interface.

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Geite, Patrik. "Medical Implant Applications of Mesoporous Silica Films." Thesis, Linköpings universitet, Nanostrukturerade material, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-154463.

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A literature review of medical implant applications of mesoporous silica films was written, highlighting the advantages and limitations of different film synthesis methods. Both films synthesized through the EISA sol-gel method and particulate films, including those synthesized through the direct growth method, were reviewed and discussed. All films were found to have their strengths and weaknesses, however, the films synthesized through the direct growth method was found to be the most promising type for coating implants. In addition to the literature review, copper-doped mesoporous silica films were synthesized on titanium grade 2 substrates. SEM shows that particles grown on all the films and EDX elemental analysis confirms the presence of copper in the material. Nitrogen physisorption measurements show that particles with incorporated copper have a higher specific surface area, and pore volume compared to un-doped particles. No copper content could be confirmed through FTIR. The particles grown on titanium substrates were more rod-like compared to the ones grown on the silicon substrates as control.

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Sendyk, Daniel Isaac. "Influência dos fatores locais, sistêmicos e relativos ao cirurgião na osseointegração de implantes dentais: uma análise sistemática das evidências científicas." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/23/23149/tde-27112017-115443/.

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Os fatores que possam promover e incrementar a osseointegração, ou prejudicar o processo biológico, aumentando o índice de falhas, têm sido cada vez mais investigados com o objetivo de ampliar indicações e as taxas de sobrevivência dos implantes dentais assim como controlar fatores adversos. O objetivo desta tese foi identificar, analisar e sintetizar as evidências científicas quanto a influência das estatinas, do envelhecimento e da experiência do cirurgião no processo osseointegração e na sobrevivência de implantes dentais. Este volume apresenta um compilado de três revisões sistemáticas orientadas pelas recomendações PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). O processo de revisão foi realizado por meio de uma busca sistemática em cinco bases de dados eletrônicas (PubMed, Scopus, Web of Science, Embase e Cochrane Library), além de busca manual nas referências bibliográficas dos estudos incluídos. A meta-análise, quando cabível, foi realizada com o auxílio do software Review Manager (RevMan, Versão 5.3). O grau de heterogeneidade entre os estudos foi verificado por meio do teste Q de Cochran e I2. O viés das publicações foi avaliado com o auxílio das escalas Newcasttle-Ottawa e Cochrane Collaboration\'s Tool. A síntese dos dados permitiu a publicação de três artigos científicos dispostos nesta tese.
Factors that may promote and enhance osseointegration, or impair the biological process, have been increasingly investigated in order to expand the indications and survival rates of dental implants and control the adverse factors. The aim of this thesis is to identify and summarize the scientific evidence of statins, ageing and surgeon related factors that can influence osseointegration and survival of dental implants. This volume presents a compilation of three systematic reviews structured by PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The review process was carried out through a systematic search in five electronic databases (PubMed, Scopus, Web of Science, Embase and Cochrane Library) and bibliographical references of the included studies. Meta-analyses, when appropriate, were performed using the software Review Manager (RevMan version 5.3). The degree of heterogeneity in the studies was verified by Q Cochran test and I2. The bias of the publications was assessed with the assistance of Newcastle-Ottawa Scale and Cochrane Collaboration Tool\'s. The synthesis of the data was included in three papers prepared for this thesis.

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Schafroth, Denis Nicolas. "Effects of decontamination and implant surface characteristics on re-osseointegration following treatment of peri-implantitis /." [S.l.] : [s.n.], 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000279112.

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Deco, Camila Porto de [UNESP]. "Influência da osteoporose e álcool na osseointegração de implantes em ratas." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/87938.

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O consumo de álcool e a osteoporose, individualmente, podem afetar o metabolismo ósseo e ter influência negativa sobre tratamentos com implantes odontológicos, comprometendo sua estabilidade biomecânica. Entretanto, os efeitos da associação entre esses dois fatores na osseointegração de implantes é desconhecido. O objetivo deste trabalho foi investigar parâmetros histomorfométricos da osseointegração em ratas sob consumo de álcool associado à osteoporose. Noventa e seis ratas foram divididas conforme o tipo de dieta e quanto à presença ou ausência hormonal. Grupo G1: Sham (ovariectomia simulada), água e ração ad libitum; G2: Sham, ração e solução de etanol a 20% ad libitum; G3: Sham, ração e solução de sacarose controladas para assegurar uma dieta isocalórica à de G2; G4: ovariectomia, água e ração ad libitum; G5: ovariectomia, ração e solução de etanol a 20% ad libitum; G6: ovariectomia, ração e solução de sacarose controladas para assegurar uma dieta isocalórica à de G5. Cada grupo foi subdividido em A e B, de acordo com o tempo de osseointegração: 4 ou 6 semanas, respectivamente. Um mês após a ovariectomia ou Sham foi iniciada a dieta e um mês depois foi realizada a cirurgia para colocação dos implantes de titânio nos fêmures dos animais. Após a eutanásia, os fêmures foram avaliados por histomorfometria para quantificação da superfície de contato direto entre osso e implante. Os grupos G5 e G6 foram os que apresentaram a menor porcentagem de contato direto ossoimplante quando comparados aos demais. Conclusão: A associação entre a deficiência estrogênica, provocada pela ovariectomia, e o consumo crônico de álcool pode prejudicar a osseointegração, assim como a associação entre deficiência estrogênica e redução no consumo de nutrientes.
Alcohol intake and osteoporosis can, separately, affect bone physiology and have presented negative impacts on dental implant therapy. However, the effects of the association of both factors in the osseointegration are unknown. The aim of this study was evaluate osseointegration in rats alcohol fed and presenting induced osteoporosis. Methodology: Ninety-six female rats were divided according to diet and hormonal condition. Group G1: Sham (simulated ovariectomy), food and water ad libitum; G2: Sham, food and ethanol 20% solution ad libitum; G3: Sham, food and sucrose solution controlled to warranty an isocaloric diet in relation to G2; G4 ovariectomy, food and water ad libitum; G5 ovariectomy, food and ethanol 20% solution ad libitum; G6: ovariectomy, food and sucrose solution controlled to warranty an isocaloric diet to G5. The groups were subdivided according to time of osseointegration 4 or 6 weeks. Implants surgery was done one month after ovariectomy or Sham. After euthanasia, the femurs were removed and evaluated by histomorfometry. Results: Groups G5 and G6 showed the worse osseointegration condition. Conclusion: The association between estrogen deficiency and alcohol intake and the association between estrogen deficiency and reduced intake of nutrients can negatively affect osseointegration.

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Raines, Andrew Lawrence. "The role of biomaterial properties in peri-implant neovascularization." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41178.

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An understanding of the interactions between orthopaedic and dental implant surfaces with the surrounding host tissue is critical in the design of next generation implants to improve osseointegration and clinical success rates. Critical to the process of osseointegration is the rapid establishment of a patent neovasculature in the peri-implant space to allow for the delivery of oxygen, nutrients, and progenitor cells. The central aim of this thesis is to understand how biomaterials regulate cellular and host tissue response to elicit a pro-angiogenic microenvironment at the implant/tissue interface. To address this question, the studies performed in this thesis aim to 1) determine whether biomaterial surface properties can modulate the production and secretion of pro-angiogenic growth factors by cells, 2) determine the role of integrin and VEGF-A signaling in the angiogenic response of cells to implant surface features, and 3) to determine whether neovascularization in response to an implanted biomaterial can be modulated in vivo. The results demonstrate that biomaterial surface microtopography and surface energy can increase the production of pro-angiogenic growth factors by osteoblasts and that these growth factors stimulate the differentiation of endothelial cells in a paracrine manner and the results suggest that signaling through specific integrin receptors affects the production of angiogenic growth factors by osteoblast-like cells. Further, using a novel in vivo model, the results demonstrate that a combination of a rough surface microtopography and high surface energy can improve bone-to-implant contact and neovascularization. The results of these studies also suggest that VEGF-A produced by osteoblast-like cells has both an autocrine and paracrine effect. VEGF-A silenced cells exhibited reduced production of both pro-angiogenic and osteogenic growth factors in response to surface microtopgraphy and surface energy, and conditioned media from VEGF-A silenced osteoblast-like cell cultures failed to stimulate endothelial cell differentiation in an in vitro model. Finally, the results show that by combining angiogenic and osteogenic biomaterials, new bone formation and neovascularization can be enhanced. Taken together, this research helps to provide a better understanding of the role of material properties in cell and host tissue response and will aid in the improvement of the design of new implants.

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Han, Guang. "The synergistic role of hierarchical macro- and mesoporous implant surface and microscopic view of enhanced osseointegration." Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-120584.

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The trend for designing of a titanium implant explored using different chemical compositions and crystallinity materials until people realized that the implant surface character was another important factor affecting the rate and extent of osseointegartion. Titanium received a macroporous titania surface layer by anodization, which contains open pores with average pore diameter around 5μm. An additional mesoporous titania top layer was created that followed the contour of the macropores and having 100–200 nm thickness and a pore diameter of 10 nm. Thus, a coherent laminar titania surface layer was obtained producing a hierarchical macro- and mesoporous surface. The interfacial bonding between the surface layers and the titanium matrix was characterized by a scratch test that confirmed a stable and strong bonding of the laminar titania surface layers upon titanium. The wettability to water and the effects on the osteosarcoma cell line (SaOS-2) proliferation and mineralization of the formed titania surface layers were studied systematically by cell culture and scanning electron microscopy (SEM). A synergistic role of the hierarchical macro- and mesoporosities was revealed in terms of enhancing cell adhesion, proliferation and mineralization, when compared with the titania surface with solo porosity scale topography. For the in vivo results of the evaluation of osseointegration, an argon ion beam polishing technique was applied to prepare the cross sections of implants feasible for the high resolution SEM investigation. The interfacial microstructure between newly formed bone and implants with four modified surfaces including the new hierarchical macro- and mesoporous implant surface retrieved after in vivo tests were characterized. By this approach it has become possible to directly observe early bone formation, the increase of bone density, and the evolution of bone structure. The two bone growth mechanisms, distant osteogenesis and contact osteogenesis, can also be distinguished. These direct observations give, at microscopic level, a better view of osseointegration and explain the functional mechanisms of various implant surfaces for osseointegration.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: In press. Paper 4: Manuscript.

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Grandfield, Kathryn. "Nanoscale Osseointegration : Characterization of Biomaterials and their Interfaces with Electron Tomography." Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179445.

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Bone response is one of the key determining factors in the overall success of biomaterials intended for bone regeneration and osseointegration. Understanding the formation of bone at an implant surface may lead to the improved design of biomaterials for the future. However, due to the inhomogeneity of bone tissue at an interface, two-dimensional images often lack detail on the interfacial complexity. Furthermore, the increasing use of nanotechnology in the design and production of biomaterials demands characterization techniques on a similar nano length scale. While current analysis methods, such as X-ray tomography, transmission electron microscopy, focused ion beam microscopy and scanning electron microscopy, provide a basis for analysing biomaterials and biointerfaces, they are incapable of doing so with both nanometre resolution and three-dimensional clarity. In contrast, electron tomography may be used to characterize the three-dimensional structure of biomaterials and their interfaces to bone with nanometre resolution. In this work, hydroxyapatite scaffolds, and laser-modified titanium and Ti6Al4V implants were studied in contact with human or rabbit bone. Z-contrast electron tomography revealed that the orientation of collagen in bone apposing hydroxyapatite, titanium and Ti6Al4V implants is consistently parallel to the implant surface, where the bioactive layer that precipitates on HA is oriented perpendicular to the implant surface. With this method, complete three-dimensional nanoscale osseointegration of titanium-based implants was also established. The extension of this technique from interfacial analyses to the design of biomaterials provided an understanding of the pore structure of mesoporous titania. In further investigations, the open three-dimensional pore network, as revealed by electron tomography, showed promise as a coating that improves implant osseointegration and enables site-specific drug-delivery from an implant surface. In summary, it was demonstrated that two-dimensional characterization techniques were insufficient for the investigation of nanostructured biomaterials, as well as their interfaces to bone. Visualizing biointerfaces and biomaterials with nanometre precision in three-dimensions can expose new fundamental information on materials properties and bone response, enabling better design of biomaterials for the future.

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Perez, Miguel Angel Jaimes. "Analise fotoelastica da distribuição de tensões em implantes osseointegraveis com diferentes desenhos." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289422.

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Orientador: Jose Ricardo de Albergaria Barbosa
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-13T22:50:05Z (GMT). No. of bitstreams: 1 Perez_MiguelAngelJaimes_D.pdf: 10680088 bytes, checksum: c91b56bc63db2e1197b0228d1fc609d5 (MD5) Previous issue date: 2009
Resumo: O objetivo deste estudo foi analisar qualitativa e quantitativamente a distribuição das tensões geradas em modelos fotoelásticos após a aplicação de cargas verticais de 150N, em implantes osseointegráveis de diferentes desenhos. Foram selecionados 3 implantes: I.) Serson Implant 3,75 x 13 mm, Hexágono Externo; II.) Colosso RC 4,0 x 13 mm, Hexágono Interno; III.) Kopp 4,0 x 13 mm, Cone Morse. Para a análise da distribuição de tensões foram confeccionadas 3 hemimandibulas em resina fotoelástica a partir da duplicação de três réplicas de hemimandibulas humanas de poliuretano. Cada implante foi posicionado e fixado no interior da hemimandibula fotoelástica na região do segundo pré-molar ausente. Através do polariscópio circular pertencente ao laboratório de Materiais Dentários da Faculdade de Odontologia de Piracicaba FOP-UNICAMP, foi possível visualizar as franjas isocromáticas nos modelos. Na análise qualitativa foi observado o início da primeira franja e a distribuição das tensões quando aplicado 150N de carga. A análise quantitativa foi obtida através da formula da lei ótica das tensões, conhecendo a respectiva ordem de franja no ponto de interesse, a constante ótica do material e a espessura do modelo. Este cálculo permitiu conhecer a tensão cisalhante de cada implante. O implante cilíndrico Serson, H.E apresentou distribuição das tensões na região cervical, apical e média do implante com maior tensão cisalhante na região cervical, seguido pela região media e apical. O implante Colosso RC com H.I apresentou distribuição das tensões na região apical, cervical e média do implante com um padrão uniforme de tensões nas três regiões. O implante Kopp, com desenho cônico e C.M apresentou distribuição das tensões na região cervical, apical, e média do implante com maior concentração de tensão cisalhante na região apical, seguido pela região cervical e media conjuntamente. Baseado nos resultados e na metodologia empregada neste estudo conclui-se que os três desenhos de implantes apresentaram padrões diferentes de distribuição de tensões, observando-se menor concentração de tensões nos implantes cônicos com conexões internas H.I e C.M. O implante cilíndrico com H.E apresentou maior concentração de tensão
Abstract: This study qualitatively and quantitatively analyze the distribution of tensions generated in fotoelastic models after the application of vertical loads of 150N in osseointegrables implants of different designs. We selected 3 implants: I.) Serson Implant 3.75 x 13 mm, External Hexagon II.) Colosso RC 4.0 x 13 mm, Internal Hexagon, III.) Kopp 4.0 x 13 mm, Morse Cone. For the analysis of the distribution of tensions, 3 hemimandibles using fotoelastic resin from the duplication of three replics of human hemimandibles of polyurethane were made. Each implant was placed and fixed inside the fotoelastic hemimandibles in the region where the second pre-molar was absent. Through a circular polariscope belonging to the Dental Materials, School of Dentistry of Piracicaba (FOP - UNICAMP) laboratory was able to see the isochromatics fringes in the models. In the qualitative analysis was observed the beginning of the first fringe and the distribution of the tensions when was applied a load of 150N. A quantitative analysis was obtained through the optical formula law of the tensions, knowing the order of fringe at the point of interest, an optical constant of the material and the thickness of the model. This calculation allowed to know the cisalhante shear of each implant. The cylindrical implant Serson HE showed distribution of the tensions in the cervical, middle and apical region of the implant with great tension shear in the cervical, followed by middle and apical region. The implant Colosso RC with HI showed distribution of the tensions in the apical, cervical and middle region of the implant with a uniform pattern of the tensions in these three regions. The implant Kopp with conic design and CM showed distribution of the tensions in the cervical, apical, and middle region of the implant with great concentration of the tension shear in the apical region, followed by cervical and middle together. Based on the results and methodology used in this study, we concluded that the three designs of implants showed different patterns of distribution of the tensions, with less concentration of the tensions in the conical implants with internal connections HI and CM. The cylindrical implant with HE showed higher concentration of the tension
Doutorado
Cirurgia e Traumatologia Buco-Maxilo-Faciais
Doutor em Clínica Odontológica

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Violin, Kalan Bastos. "Implantes cerâmicos e metálicos - caracterização da osteointegração por imuno-histoquímica, lectina-histoquímica e marcadores fluorescentes." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-17112015-100334/.

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Biomateriais, cerâmicos ou metálicos, para emprego em tecido ósseo, são importantes ferramentas na medicina regenerativa com intuito de reparar, restaurar, restituir, sustentar, tratar e substituir tecido lesionado. A análise da resposta biológica aos biomateriais é um grande desafio, considerando os aspectos inerentes do tecido ósseo mineralizado e as características físicas dos biomateriais. A compreensão do comportamento celular envolvido nesse conjunto tem o intuito de desenvolver biomateriais mais aptos e adequados ao tecido ósseo o qual ele é destinado. O objetivo deste estudo foi avaliar a osteointegração de implantes cerâmicos e metálicos após ensaio in vivo, por meio de técnicas histoquímicas com colorações de Giemsa-Eosina (GE), Hematoxilina-Eosina (HE), Tricrômico de Masson-Goldner (MG), Tricrômico de Masson (TM), Tricrômico de Gomori (GO) e Picrossírus (PS), Azul de Toluidina (AT) além de técnicas imunohistoquímica (IHQ), lectina-histoquímica (LHQ) e marcadores fluorescentes. Implantes cerâmicos à base de fosfatos de cálcio: hidroxiapatita (HAp), β-fosfato tricálcico (β-TCP) e mistura dos dois (BCP) 1:1 em peso, foram produzidos por gelcasting de espuma e pela inovadora técnica da bola de neve. Os implantes à base de titânio comercialmente puro (Ticp) e da Liga Ti-13Nb-13Zr (Liga) foram produzidos por metalurgia do pó; sendo macroporosos, com a adição de diferentes polímeros naturais, ou microporosos, com elevadas densidades, submetidos a diferentes tratamentos de superfície. A avaliação da osteointegração foi realizada em tíbia de coelhos após períodos de reparação, em conjuntos osso-implante: não-descalcificados e descalcificados. Na análise histológica por microscopia óptica com colorações histoquímicas, os conjuntos apresentaram crescimento ósseo com osteointegração em todos os implantes. A análise por fluorescência mostrou as fases e áreas marcadas de acordo com o período de aplicação do marcador, indicando intenso remodelamento ósseo em todo o osso, o crescimento ósseo no interior dos poros e ao redor dos implantes para os marcadores tetraciclina e calceína. Com a análise de IHQ foram avaliados os marcadores para osteopontina (OP), osteonectina (ON) e osteocalcina (OC), e com LHQ foram avaliadas 5 lectinas. O melhor marcador por IHQ foi para OP, havendo correlação entre a marcação com WGA pela LHQ e OP pela IHQ. A técnica de LHQ foi bem sucedida em criar perfis de comparação entre os biomateriais. A maior marcação por RCA-1 para todos os implantes cerâmicos e metálicos, indicam que esta é um promissor marcador para diferenciação em estudos de osteointegração, bem como a marcação por sWGA e PNA nos implantes de Liga.
The use of biomaterials in bone, whether ceramic or metallic, are important tools for regenerative medicine aiming to repair, restore, restitute, support, treat and substitute damaged tissue. The evaluation of biological response towards biomaterials is a big challenge considering the inherent aspects of mineralized bone tissue and physical characteristics of biomaterials. The understanding of the cellular behavior involved will propitiate the development of more fit and adequate biomaterials to the targeted bone. The objective of this study was to evaluate the osseointegration of ceramic and metallic implants after in vivo testing on bone, with histochemical staining techniques as Giemsa-Eosin (GE), Hematoxylin-Eosin (HE), Masson-Goldners Trichrome (MG), Massons Trichrome (MT), Gomoris Trichrome (GT), Picrosirius Red (PS), Toluidine Blue (TB), besides Immunohistochemistry (IHC), Lectinhistochemistry (LHC) and Fluorescent labeling. The ceramic implants were produced using calcium phosphates: hydroxyapatite (HAp), β-tricalcium phosphate (β-TCP) and their biphasic mixture (BCP) 1:1 by weight, as ceramic foam by gelcasting or as ceramic spheres obtained by the innovative Snowballing technique. The metallic implants were produced using commercially pure titanium (cpTi) and alloy Ti-13Nb-13Zr (Alloy) by powder metallurgy, using natural polymers as additives to achieve macroporosity and microporous without additives and different surface treatments. The osseointegration evaluation was performed on implanted tibia bone of New Zealand White rabbits after repair period in bone-implant samples either decalcified or undecalcified. Histological analysis of stained slides with optical microscopy showed samples with bone ingrowth and osteointegration on all implants. The Fluorescent analysis evidenced the bone growth phases and areas according to each marker injection period. Intense remodeling process throughout the bone, bone ingrowth inside the pores and surrounding the implants was observed with the markers tetracycline and calcein. The IHC analysis was performed using markers for osteopontin (OP), osteocalcin (OC) and osteonectin (ON), and LHC analysis using five lectins. The best marker by IHC was OP; with correlation between the result of lectin WGA and the antibody for OP. The LHC technique was successful creating profiles for comparison between biomaterials. The results of RCA-1 for all ceramic and metallic implants indicates that this is a promising marker for differentiation at osseointegration studies, as well as the results of sWGA and PNA for Alloy implants.

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Fauroux, Marie-Alix. "Ostéo-intégration des implants dentaires à partir de l’étude de recherche clinique ZIR-ROC : matériaux, techniques opératoires, limites et perspectives." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT030.

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Introduction : Depuis les premiers implants dentaires Bränemark, les techniques chirurgicales et les matériaux implantaires ont évolué. La référence en terme de matériau implantaire est le Titane. Cependant, d’autres matériaux comme le Zircone ont été proposés pour suppléer le Titane en cas d’allergie au Titane mais aussi pour améliorer la bio-intégration de l’implant dentaire et l’esthétique. Les facteurs de risques d’échec implantaire des implants en Titane incluent, entre autre, l’hygiène orale, la consommation de tabac et la mise en charge immédiate. Objectif : L’étude ZIR-ROC a donc été menée dans le but d’étudier le taux de survie de ces implants zircone après 2 ans de suivi, de recueillir des informations sur l’intégration tissulaire des implants et de rechercher les facteurs de risque d’échec des implants en Zircone. Matériel et méthode : l’étude ZIR-ROC a été menée dans le service de chirurgie orale du CHU de Montpellier sur des implants monobloc en Zircone de la société Paris Implant®. La pose de 43 implants a été déterminée pour permettre l’analyse statistique des résultats. Le forage et l’insertion des implants ont été réalisés à l’aide du système de chirurgie guidée 2ingis®. La variable principale pour évaluer l’ostéo-intégration des implants a été le score délivré par le Periotest®. 22 variables secondaires ont été recueillies tels que les indices gingivaux et de plaque ainsi que l’analyse rétro-alvéolaire. Les données ont été relevées juste avant la chirurgie implantaire, ainsi qu’à 1 semaine, 4 semaines, 5 mois, 1 an et 2 ans. La méthode de Kaplan-Meier, le modèle de Cox et les analyses en composantes principales ont été utilisés pour l’analyse statistique. Résultats : Tous les implants ont présenté une bonne stabilité primaire post-opératoire (valeurs du Periotest comprises entre -8 et +1 ; moyenne à -5,7). Le taux d’échec implantaire a atteint 31% après les 5 premiers mois d’ostéo-intégration. Une mobilité clinique a été observée pour les implants perdus. Les facteurs de risque décrits dans la littérature ont été retrouvés dans le modèle de Cox avec une significativité pour la consommation de tabac et d’alcool et sans significativité statistique pour la densité osseuse ou encore la mise en place d’une couronne provisoire. Par ailleurs, la présence de plaque et d’inflammation gingivale a été observée en faible quantité sur les implants en Zircone. Discussion et conclusion : Le Zircone apparaît comme un matériau biocompatible pour des implants dentaires. Les causes des échecs implantaires précoces observés sont probablement multiples et cette étude n’a pas permis de démontrer l’implication seule de la Zircone dans ces échecs. La recherche des facteurs d’échecs implantaires a conduit à évaluer la technique chirurgicale utilisée pour cette étude mais aussi le dessin de l’implant. De plus, une étude in vitro comparant des implants à base de Zircone et de Titane a été entreprise pour évaluer l’affinité de cellules souches d’origine dentaire pour les 2 matériaux
Introduction: Since first Bränemark dental implants were implanted, operative surgery and materials for implantation have evolved. Titanium was the gold standard for dental implant material. But others materials like Zirconium were studied in replacement of Titanium due to allergy, bio-integration end aesthetic reasons. Contributing risk factors of Titanium implant failure include oral hygiene, tabacco and early loading among others factors. Objective: The aim of this clinical study was to evaluate survival rate of Zircon implants after 2 years, to collect information for tissue integration of Zirconium implant and to identify risk factors for Zircon implant failure. Material and Methods: ZIR-ROC study, conducted in the Oral Surgery Departement in Montpellier University Hospital, used zircon monobloc (ZIR-ROC®) implants (Paris Implant Society®). 43 implants were required for statistical analysis. Drilling and implantation were conducted with 2ingis® surgical guide system. The Periotest® value was the first endpoint for the implant osseointegration analysis. Gingival and dental plaque indices as well as intraoral X-ray analysis were part of the 22 secondary variables. Data were collected just after implantation surgery, and then, 1 week, 4 weeks, 5 months, 1 year and 2 years after implantation. Kaplan-Meier method, Cox regression model and principal component analysis were used for statistical analysis. Results: All implants showed postoperative optimal primary stability (Periotest® values between -8 and +1; mean: -5,7). Implants failure rate reached 31 percent after the 5 initial months of osseointegration. Clinical mobility was observed for the failed implants. Risk factors published in the scientific literature were observed in the Cox regression model with significant statistical effect for tobacco and alcohol consumption but without significant statistical effect for osseous density or even temporary crown insertion. Furthermore, gingival inflammation and dental plaque presence were low on Zircon implant. Discussion and Conclusion: Zirconium remains a biocompatible material for dental implantation but there were probably many reasons for the observed early implant failures and this study could not demonstrate the only involvement of Zirconium based material. Operative surgery used in this clinical study and the design of the implants were studied for researching other risk factors. In addition, an in vitro study comparing Zirconium versus Titanium as gold standard, was conducted for testing affinity of dental stems cells on Titanium and Zirconium-based dental materials

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Lotz, Ethan M. "Designing Biomimetic Implant Surfaces to Promote Osseointegration under Osteoporotic Conditions by Revitalizing Mechanisms Coupling Bone Resorption to Formation." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5908.

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In cases of compromised bone remodeling like osteoporosis, insufficient osseointegration occurs and results in implant failure. Implant retention relies on proper secondary fixation, which is developed during bone remodeling. This process is disrupted in metastatic bone diseases like osteoporosis. Osteoporosis is characterized low bone mass and bone strength resulting from either accelerated osteoclast-mediated bone resorption or impaired osteoblast-mediated bone formation. These two processes are not independent phenomena. In fact, osteoporosis can be viewed as a breakdown of the cellular communication connecting bone resorption to bone formation. Because bone remodeling occurs at temporally generated specific anatomical sites and at different times, local regulators that control cross-talk among the cells of the BRU are important. Previous studies show Ti implant surface characteristics like roughness, hydrophilicity, and chemistry influence the osteoblastic differentiation of human MSCs and maturation of OBs. Furthermore, microstructured Ti surfaces modulate the production of factors shown to be important in the reciprocal communication necessary for the maintenance of healthy bone remodeling. Semaphorin signaling proteins are known to couple the communication of osteoblasts to osteoclasts and are capable of stimulating bone formation or bone resorption depending on certain cues. Implant surface properties can be optimized to exploit these effects to favor rapid osseointegration in patients with osteoporosis.

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Guo, Gao. "Retrospektive Untersuchung zu implantatverankerten Ohrepithesen." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2005. http://dx.doi.org/10.18452/15237.

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Das Ziel dieser Arbeit war es, das klinische Resultat der implantatverankerten Ohrepithese retrospektiv zu untersuchen. Es wurden die Daten von 46 Patienten erhoben, die von 1992 bis 2003 mit implantatverankerten Ohrepithesen versorgt wurden. Bei 20 Patienten mit 53 Implantaten wurde eine spezielle Nachuntersuchung zur Beurteilung der periimplantären Weichgewebssituation durchgeführt. Zwei objektive klinische Parameter, die Sondierungstiefe und die Sulcus Fluid Flow Rate (SFFR), wurden hierfür angewendet. Die subjektive Beurteilung der Hautreaktionen war durch das Graduierungsystem von Holgers klassifiziert. 24 Patienten wurden mit Hilfe eines einheitlichen Fragebogens über die Zufriedenheit und auf mögliche Beschwerden befragt. Die kongenitalen Ohrmissbildungen (62,5%) waren die häufigsten Indikationen bei dieser Behandlung. 156 Implantate und eine Trägerplatte (Epitec-System®) bei den 46 Patienten inseriert, darunter waren 23 Implantate aus dem EO-System®, sowie 133 aus dem Brånemark-System®. Intraoperative Komplikationen traten bei der Implantatinsertion nicht auf. Die Implantationserfolgsrate liegt bei 100%. Bei 34 Patienten (74%) wurden insgesamt 42-mal Hautreaktionen (Entzündungen, Blutungen, Schwellungen) während der Nachkontrolle registriert. Die durchschnittliche Tragezeit der Ohrepithesen betrug 2,7 Jahre. Periimplantäre Hauttaschen sind in unserer Studie bei allen untersuchten Implantaten beobachtet worden. In der speziellen Nachuntersuchung lag der mittlere Wert der Sondierungstiefe und der SFFR bei 2,1 mm bzw. 1,8 mm. Zwischen beiden Parameter wurde eine starke Korrelation festgestellt: Je tiefer die Sondierungstiefe desto höher waren die Werte der SFFR. Bei 22 Implantaten (41,5%) ergaben sich keine Hautreaktionen. Die Entzündungen wurden nur an vier Implantaten (7,5%) beobachtet. 91,7% der befragten Patienten waren mit ihrer Ohrepithese zufrieden. Anhand unserer Studie, dass die implantatverankerten Ohrepithese heute ausgezeichnete und stabile Langzeitergebnisse erzielt werden können. Die tiefe Hauttasche spricht für ein Zeichen der periimplantären Entzündung und eine Notwendigkeit einer periimplantäreren Hautausdünnung.
The purpose of this study is to retrospectively evaluate the clinical results of the implant-retained auricular prosthesis. The data of 46 patients who were treated between 1992 and 2003 with implant-retained auricular prosthesis were evaluated. 20 patients with 53 implants were re-examined to evaluate the periimplant soft tissue situation with two objective clinical parameters periimplant sulcus probing depth and sulcus-fluid-flow-rate (SFFR). The subjective evalution of skin reactions around the abutments was classified as reported by Holgers. Satisfaction and eventual complications were evaluated in 24 patients by using standardized Questionnaires. Congenital malformation (62.5%) was the most common indications for auricular prostheses. A total of 156 implants and a plate (Epitec-System®) were placed in 46 patients, 23 of which were EO-System®, and 133 were Brånemark-System®. No intraoperative complications were reported during the insertion of implants. The implant survival rate was 100%. 42 times of skin reactions (inflammation, bleeding, swelling) were registered in 34 patients. The average wearing time of the prosthesis was 2.7 year. Skin pockets were found in all of the 53 re-examined implants. The middle value of sulcus probing depth and SFFR was respectively 2.1 mm and 1.8 mm. A strong correlation was found between the two parameter, which suggests that a deeper sulcus always presents a high value of SFFR. No adverse skin reactions was found in 22 implants (41.5%). Severe inflammation was observed in only 4 implants (7.5%). 91,7% of patients were satisfied with their prostheses. From this study it can be concluded that the implant-retained auricular prostheses offer a good and secure perspective for patients. The deep sulcus shows a sign of periimplantitis and a surgical thinning of subcutaneous periimplant soft tissue should be perfomed to eliminate it.

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Barbara, Mary Anne Moreira. "Influência da Superfície do implante e da laserterapia na osseointegração, em ratas osteopênicas /." São Jose dos Campos : [s.n.], 2009. http://hdl.handle.net/11449/95864.

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Orientador: Luana Marotta Reis de Vasconcellos
Banca: Yasmin Rodarte Carvalho
Banca: Carlos Eduardo Dias Colombo
Resumo: Com o aumento da expectativa de vida da população é importante o estudo de tratamentos alternativos e de biomateriais que visam auxiliar no processo de osseointegração em pessoas com osteoporose. O presente estudo avaliou e comparou a osseointegração de implantes cilíndricos de superfície porosa com implantes cilíndricos de superfície rugosa, ambos de titânio, em ratas osteopênicas e normais, por meio de análise histológica e histomorfométrica. Avaliou também a influência do tratamento com laser de baixa potência (Arseneto de Gálio Alumínio) sobre a osseointegração. Os implantes foram inseridos em 84 ratas, cada rata recebeu um implante poroso no fêmur esquerdo e um implante rugoso no direito. Quarenta e dois dos animais foram submetidos à cirurgia de ovariectomia (OVZ) e 42 foram falsamente operados (SHAM). Após um mês, as ratas foram divididas em 4 grupos, com 21 animais cada, de acordo com o tratamento recebido: a) grupo 1 (SHAM): cirurgia de colocação dos implantes (CI); b) grupo 2 (SHAM): CI e aplicação do laser de baixa potência (LLLT); c) grupo 3 (OVZ): CI; d) grupo 4 (OVZ): CI e LLLT. Sete animais de cada grupo, selecionados aleatoriamente, foram sacrificados 2, 4 e 6 semanas após a cirurgia, os fêmures contendo os implantes foram submetidos à análise histológica e histomorfométrica. Na análise histológica observou-se que houve osseointegração em ambos implantes nos diferentes grupos. Após avaliação da análise histomorfométrica verificou-se que o grupo 4, os implantes do tipo poroso, com animais sacrificados 4 semanas após a cirurgia de implante exibiu maior porcentagem de neoformação óssea, seguido do grupo 2, com implante poroso 4 e 6 semanas de período de sacrifício. Concluiu-se que a laserterapia melhora significantemente a neoformação óssea e que os implantes de superfície porosa apresentam maior área para contato na interface osso-implante.
Abstract: With increasing life expectancy of the population is important to the study of alternative treatments and biomaterials which aim to assist in the process of osseointegration in people with osteoporosis. .This study involved an assessment and comparison of the osseointegration of cylindrical titanium implants with porous surfaces and with rough surfaces in osteopenic rats, based histological and histomorphometric analyses. An evaluation was also made of the influence of low level laser therapy (LLLT) with gallium-aluminum arsenate (Ga-Al-As) on osseointegration. The implants were placed in 84 rats, two per rat, i.e., a porous implant in the left femur and a rough implant in the right femur Forty-two of the animals were then ovariectomized (OVZ) while the other 42 were subjected to a sham ovariectomy (SHAM). After one month the rats were divided randomly into four groups of 21 animals each, according to treatment received: a) group 1 (SHAM) implant surgery (IS); b) group 2 (SHAM) IS and low-level laser therapy (LLLT); c) group 3 (OVZ): IS; d) group 4 (OVZ) IS and LLLT. Seven animals from each group were selected randomly and killed 2, 4 and 6 weeks after surgery and the histomorphometric analyses. The histological analysis revealed that osseointegration occurred in both types of implants in all the groups. The histomorphometric analysis indicated that the porous implants in the group 4, killed 4 weeks after implantation, showed the highest percentage of new bone formation, followed by the porous implants in group 2, killed 4 and 6 weeks after implantation. It was concluded that laser therapy significantly improves new bone formation and that implants with porous surfaces have a larger contact area at the bone-implant interface.
Mestre

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Ventura, Alexandra Margarida Pires. "Complicações microbiológicas na interface implante-pilar." Master's thesis, [s.n.], 2015. http://hdl.handle.net/10284/5145.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária
A implantologia é uma área em expansão na medicina dentária, contribui em grande escala para o sucesso dos tratamentos reabilitadores. O sucesso desta técnica esta provado em muitas publicações, no entanto os fracassos também ocorrem, deste modo os investigadores trabalham do sentido de perceber a ocorrência desses mesmos fracassos para os poderem colmatar. O princípio da osteointegração é um princípio chave no sucesso desta técnica, sendo que pode ser influenciada por fatores relacionados com o próprio paciente, fatores relacionados com o implante e condições cirúrgicas. Outro ponto chave é a preservação dos tecidos peri implantares, uma vez que são extremamente valiosos em todo este processo, pois o seu comprometimento pode desencadear as chamadas complicações microbiológicas, comprometendo o êxito da reabilitação. A ocorrência de complicações microbiológicas leva a ocorrência de infiltração na interface implante pilar que por sua vez desencadeia um processo inflamatório responsável pelo aparecimento de doenças peri implantares. Varias conexões de implantes têm sido analisadas no sentido de “encontrar” a que reúne um conjunto de características que minimizam a infiltração na interface implante pilar e consequentemente menor número de implantes fracassados. Cone Morse têm sido a conexão que demonstra melhor eficiência clínica nas reabilitações com implantes. Com este trabalho pretendo estudar o comportamento microbiológico na interface implante-pilar através da análise e comparação dos vários artigos que abordam este tema. Implantology is an expanding field within dental medicine. It contributes to a great extent to the success of rehabilitation treatments. The success of this technique has been proven through many published research papers, however, failures also occur. Thus, researchers´ work intends to understand theoccurrence of those failures in order to be able to rectify them. The principle of the osseointegration is a key principle when it comes to the success of this technique for it can be influenced by factors related to the patient or the implant and surgical conditions. Another key point is the preservation of the peri-implant tissues since they are extremely important in this procedure. Indeed, if they are damaged, it can trigger microbiological complications which, in turn, will compromise the success ofthe rehabilitation. When microbiological complications occur, there is an infiltration in the implantabutment interface which will trigger an inflammatory response, responsible for the appearance of peri-implant diseases. Several connections of implants have been analysed in order to find the one that combines a set of characteristics which minimise the infiltration in the implantabutment interface and, consequently, the number of failed implants. Cone Morse has proven to be the most clinically efficient connection with regard to oral rehabilitation with dental implants. With this work I intend to study the microbiological behaviour on the implant-abutment interface through the analysis and comparison of the several scientific papers that deal with this subject.

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Eggert, Donna Marie. "Case Study Analysis Of Osseointegration And Limb-Salvaging Technology In Animal Subject's Bilateral Osseointegrated Implant Journey With Potential Human Translation." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/332675.

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In the twenty-first century, new cutting-edge osseointegration technology is improving quality of life. Osseointegration is a new technique to suspend an implant prosthetic device for individuals with a limb-loss. The science of osseointegration is not clearly understood although there appears to be a special relationship between pure titanium that promotes activation of our bone building cells and bone remodeling. Direct bone-anchored osseointegration to integrate a foreign device into the body without the body rejecting the prosthesis is the new technology lacking knowledge and research clinical cases for human translation. The objective of the case study was to review the science of bone-anchored osseointegration as a limb-salvaging technique and potential translation to humans using a canine model in a well-defined control study. Aims were to enhance knowledge technology, improve mobility, decrease pain to improve quality of life and influence health care practices. By the year 2050, the projected number of American amputees is expected to reach 3.6 million. Many people depend on artificial limbs to perform their activities of daily living. Often these limbs start developing complications associated with stump-socket designs such as separation from the human tissue, poor fit with repeated fittings, recurrent skin infections, ulcers and pressure sores due to non-uniform pressure distribution over the socket contact area and pain which decreases their mobility. Since 2001, close to 28,500 American troops have been wounded in combat in Iraq and Afghanistan. Greater than 24,600 of them have survived their injury, the highest survival rate of any war in the history of the United States. Sadly, 700 of these services members have lost at least one limb from amputations. Lower limb amputations are still performed above the knee as not enough bone can be preserved below the knee for prosthesis. Osseointegration with limb-salvaging techniques could enhance mobility and quality of life for those individuals who sacrifice their limbs defending our freedoms.

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Vasconcelos, Karla de Faria 1983. "Análise microestrutural de sítios ósseos implantares da maxila reconstruídos com enxerto autógeno e xenógeno = Micro-computed tomography of maxillary implant sites reconstructed with autogenous and xenogenous bone graft." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288877.

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Orientador: Frab Norberto Boscolo
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O conhecimento da microarquitetura óssea desempenha importante papel no sucesso das reconstruções ósseas e posterior reabilitação com implantes dentários. Os objetivos dessa pesquisa foram: 1. Avaliar a microarquitetura óssea de sítios da maxila, que foram reconstruídos com enxertos ósseos, autógeno e xenógeno e 2. Avaliar tridimensional e bidimensionalmente a formação óssea na superfície dos parafusos de fixação (BIC-Bone-to-implant contact). Doze amostras contendo parafusos de fixação recobertos por 0,5 a 1mm de osso humano foram removidas com auxílio de uma broca trefina, após seis meses da colocação de blocos de enxerto em maxila de 8 pacientes, cinco mulheres e três homens, com média de idade entre 50 anos. Sete de sítios xenógenos e cinco de autógenos. As amostras foram avaliadas por meio de imagens obtidas pelo microtomógrafo SkyScan 1173 e por meio da técnica histológica de Stevenels blue e Van Giesen red. Para caracterizar a microarquitetura foram avaliados: a razão volume ósseo/volume tecidual, espessura das trabéculas, distância trabecular, número de trabéculas e densidade de conectividade, em três áreas distintas (enxerto/transição/osso nativo). O cálculo do BIC 2D foi realizado em imagens histológicas e microtomográficas. O BIC 3D foi viabilizado em áreas selecionadas em 17 amostras, entretanto, apenas em imagens adquiridas por microtomografia. Quando os parâmetros da microarquitetura foram comparados entre as áreas, foram observadas diferenças estatísticas (p<0,05) na espessura e distância das trabéculas, entre a área de osso nativo e do enxerto, apenas nas amostras autógenas. As amostras xenógenas não apresentaram diferenças entre as áreas. Quando os dois tipos de enxerto foram comparados entre si, diferenças estatísticas (p<0,05) foram encontradas entre o volume de tecido ósseo, espessura entre as trabéculas e a distância entre as trabéculas. O cálculo do BIC 2D revelou semelhança entre as técnicas (p=0,802) e também entre os tipos de enxerto (p=0,097). Avaliando os valores do BIC 3D, observou-se diferença estatística significante nos valores do BIC entre as diferentes áreas, osso e enxerto, com valores mais altos nas áreas de osso nativo. Esses dados estruturais e observações obtidas a partir de imagens microtomográficas proporcionam valiosa caracterização desses sítios e oportunidade de futuras correlações com estudos de elementos finitos e resultados clínicos
Abstract: The knowledge of bone microarchitecture is an important role in the success of bone reconstructions and following rehabilitation with dental implants. Thus, the main objectives of this study were: 1) To characterize the microarchitecture of implant bone sites reconstructed with bone grafts and 2) To assess in two and three-dimensions the percentage of bone in contact with bone graft fixing screws (BIC-Bone-implant contact). Six months after graft placement of blocks in the maxilla of eight patients (five women and three men, with a mean of 50 years of age) twelve samples containing fixing screws covered by 0.5 to 1 mm of human bone were removed using a trephine drill. Five were from sites that had received autogenous grafts and seven from sites that had received xenogeneic grafts. Samples were evaluated by micro tomography images obtained by the SkyScan 1173 (Bruker, Kontich, Belgium) device and by histological technique with Stevenels blue e Van Giesen red solutions. To characterize the bone microarchitecture, bone volume, trabecular thickness, trabecular distance, trabecular number and connectivity in three distinct areas (graft / transition / native bone) were evaluated. The 2D BIC was performed in histological and microtomography images. The 3D BIC was performed only in images acquired by microtomography in whole sample. When the microtomography bone parameters were compared between areas, statistical differences were noted only in the thickness and distance of the trabecular area between the native bone and autogenous graft (p<0.05). No statistically significant differences were observed between these areas in the xenogenous sample. When the parameters were compared between two types of grafts, statistical differences were found between the bone volume (p<0.05), the trabecular thickness (p<0.05) and trabecular separation (p<0.05).While calculating the BIC 2D revealed similarity when comparing values obtained by both techniques (p=0.802), and both grafts (p=0.097). It was observed statistically significant difference in values of BIC 3D in different areas (bone and graft) (p=0.0021) with the highest values in areas of native bone. The structural data and observations obtained from micro-computed tomography images provided valuable characterization of sites that received bone grafts and the opportunity for future correlations with finite element studies and clinical outcomes
Doutorado
Radiologia Odontologica
Doutora em Radiologia Odontológica

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Kayatt, Fernando Esgaib [UNESP]. "Análise experimental de copolímero na estabilidade primária de implantes osseointegráveis: avaliação microscópica em ratos." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/101055.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Sin Implantes
A estabilidade primária na instalação de implantes dentários é uma das determinantes principais no processo de osseointegração. Algumas situações clínicas impossibilitam o travamento adequado do implante. A diástase provocada por sobrefresagem ou implantações pós-exodônticas indicam o uso de materiais para ocupar este espaço. O objetivo deste estudo foi analisar o uso de copolímero a base de ácido poliláctico na estabilidade primária de implantes osseointegráveis, realizando uma avaliação microscópica através de fluorocromos. Para isso, foram utilizados 14 cilindros de Ti cp GII instalados na tíbia de ratos, divididos em: Grupo Implante Travado (GIT) e Grupo Implante e Biomaterial (GIB), nos períodos de 7, 15 e 21 dias. Resultado: Os implantes suportaram 3N.cm de torque reverso e não foram encontradas diferenças estatisticamente significantes, nos períodos finais, entre as médias das áreas ao redor do implante. O copolímero de PLA/PGA proporcionou o posicionamento dos implantes e não obstou a deposição óssea.
The primary stability in the installation of dental implants is one of the main prerequisite in the osseointegration process. Some clinical situations disable the adequate stability of the implantation. A gap occurred between the bone and the implant provoked by overdrilling or tooth extractions sockets implantations indicates the use of biomaterials to occupy this space. The aim of this study was to analyze the use of PLA/PGA copolymer in the primary stability of osseointegrated implants, through removal torque test and a microscopic evaluation with fluorescent bone markers. For this, 14 cylinders of Ti cp GII had been installed in the tibia of rats, divided in: Group Implant with Stability (GIT) and Group Implant and Biomaterial (GIB), in the periods of 7, 15 and 21 days. Result: The implantations had supported 3N.cm of removal torque and had not been found differences statistically significant, in the final periods, between the averages of the areas of the periphery of the implants. The PLA/PGA copolymer kept the implants position and did not hinder the bone deposition.

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Martinez, Miró Marina Verfasser], and Michael [Akademischer Betreuer] [Veith. "Topographical control and characterization of Al/Al2O3 nanowire coatings for improved osseointegration of implant materials / Marina Martinez Miró. Betreuer: Michael Veith." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2013. http://d-nb.info/1052904602/34.

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Santos, Marco Paulo Soares dos. "A new concept model for instrumented active orthopaedic implants." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16315.

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Doutoramento em Engenharia Mecânica
Total hip replacement (THR) is one of the most performed surgical procedures around the world. Millions of THR are carried out worldwide each year. Currently, THR revision rates can be higher than 10%. A signiﬁcant increase of the number of primary and revision THRs, mainly among patients less than 65 years old (including those under 45 years old) has been predicted for the forthcoming years. A worldwide increase in the use of uncemented ﬁxation has also been reported, incidence caused mainly by the signiﬁcant increase of more active and/or younger patients. Besides the signiﬁcant breakthroughs for uncemented ﬁxations, they have not been able to ensure long-term implant survival. Up to date, current implant models have shown evidences of their inability to avoid revision procedures. The performance of implants will be optimized if they are designed to perform an eﬀective control over the osseointegration process. To pursue this goal, improved surgical techniques and rehabilitation protocols, innovative bioactive coatings (including those for controlled delivery of drugs and/or other bio-agents in the bone-implant interface), the concepts of Passive Instrumented Implant and Active Instrumented Implant have been proposed. However, there are no conclusive demonstrations of the eﬀectiveness of such methodologies. The main goal of this thesis is to propose a new concept model for instrumented implants to optimize the bone-implant integration: the self-powered instrumented active implant with ability to deliver controlled and personalized biophysical stimuli to target tissue areas. The need of such a new model is demonstrated by optimality analyses conducted to study the performance of instrumented and non-instrumented orthopaedic implants. Promising results on the potential of a therapeutic actuation driven by cosurface-based capacitive stimulation were achieved, as well as for self-powering instrumented active implants by magnetic levitation-based electromagnetic energy harvesting.
A artroplastia total da anca (THR) é um dos procedimentos cirúrgicos mais realizados à escala global. Milhões de THRs são realizadas todos os anos em todo o mundo. Atualmente, as taxas de revisão destas artroplastias podem ser superiores a 10%. O número de THRs primárias e de revisão têm aumentado e estima-se que cresçam acentuadamente nos próximos anos, principalmente em pacientes com idades inferiores a 65 anos (incluindo aqueles com menos de 45 anos). Também se tem veriﬁcado uma tendência generalizada para o uso de ﬁxações não cimentadas, incidência principalmente causada pelo aumento signiﬁcativo de pacientes mais jovens e/ou activos. Embora se tenham realizado avanços científicos no projeto de implantes não cimentados, têm-se veriﬁcado o seu insucesso a longo-prazo. Encontram-se evidências da ineﬁcácia dos modelos de implantes que têm sido desenvolvidos para evitar procedimentos de revisão. O desempenho dos implantes será otimizado se estes foram projetados para controlarem eﬁcazmente o processo de osseointegração. Para se alcançar este objetivo, têm sido propostas a melhoria das técnicas cirúrgicas e dos protocolos de reabilitação, a inovação dos revestimentos (onde se incluem os revestimentos ativos projetados para a libertação controlada de fármacos e/ou outros bio-agentes) e os conceitos de Implante Instrumentado Passivo e Implante Instrumentado Ativo. Contudo, não existem demonstrações conclusivas da eﬁcácia de tais metodologias. O principal objetivo desta tese é propor um novo modelo de conceito para implantes instrumentados para se otimizar a integração osso-implante: o implante instrumentado ativo, energeticamente auto-suﬁciente, com capacidade de aplicar estímulos biofísicos em tecidos-alvo de forma controlada e personalizada. A necessidade de um novo modelo é demonstrada através da realização de análises de otimalidade ao desempenho dos implantes instrumentados e não-instrumentados. Foram encontrados resultados promissores para o controlo otimizado da osseointegração usando este novo modelo, através da atuação terapêutica baseada na estimulação capacitiva com arquitetura em co-superfície, assim como para fornecer energia elétrica de forma autónoma por mecanismos de transdução baseados em indução eletromagnética usando conﬁgurações baseadas na levitação magnética.

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Jayme, Sérgio Jorge. "Efeito de diferentes tempos de ativação sobre a estabilidade e resposta óssea ao redor de implantes dentários. Estudo por análise de freqüência de ressonância e histomorfométrico em cães." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-11052009-170456/.

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Propósito: O objetivo deste estudo foi avaliar a estabilidade primária com análise de freqüência de ressonância e a resposta óssea por histomorfometria em implantes sob tratamento com carga imediata e carga precoce. Material e método: Foram colocados três implantes Replace Select (Nobel Biocare, Suécia) em cada lado da mandíbula de 8 cães, totalizando 48 implantes no estudo. Um par de implantes foi selecionado para o protocolo de carga imediata (CI). Após sete dias, o segundo par de implantes recebeu as próteses para o protocolo de carga precoce (CP). Catorze dias após a colocação dos implantes, o terceiro par de implantes recebeu as próteses para o protocolo de carga precoce tardia (CPT). Em cada período foi medida a estabilidade dos implantes por freqüência de ressonância. Após o período total de doze semanas da colocação das próteses os animais foram sacrificados e os espécimes foram preparados para análise histomorfométrica. As diferenças entre os tempos de carregamento para os seguintes parâmetros: estabilidade, contato ossoimplante (COI), densidade óssea (DO) e perda da crista óssea (PCO) foram avaliadas usando ANOVA. Resultados: Os valores iniciais de estabilidade (ISQ) dos implantes foram: 77,88 ± 4,61 para CI, 79,73 ± 3,55 para CP e 79,64 ± 3,00 para CPT, sem diferença estatisticamente significante (p=0,30). Os valores finais de estabilidade foram 80,46 ± 4,23 para CI, 81,88 ± 3,55 para CP e 81,88 ± 3,42 para CPT, também sem diferença estatística (p=0,47). Para avaliar a estabilidade dos implantes em função do tempo, foi realizada ANOVA para amostras repetidas e para cada grupo foi detectado aumento significativo da estabilidade ao final do experimento (p=0,003). A interação método de carregamento versus tempo não foi significativa (p=0,97). A porcentagem de COI para CI foi 77,9 ± 1,71%, para CP foi 79,25 ± 2,11% e para CPT foi 79,42 ± 1,49%. A porcentagem de DO para CI foi 69,97 ± 3,81%, para CP foi 69,23 ± 5,68% e para CPT foi 69,19 ± 2,90%. A PCO para CI foi 1,57 ± 0,22 mm, para CP foi 1,23 ± 0,19 mm e para CPT foi 1,17 ± 0,32 mm. Não foi observada diferença estatística para nenhum dos parâmetros avaliados (p>0,05). Conclusão: Considerando a estabilidade primária, contato osso-implante, densidade óssea ao redor do implante e perda da crista óssea em cães, conclui-se que não existem diferenças estatisticamente significantes num prazo de até 12 semanas para implantes submetidos à ativação imediata, em 7 dias ou 14 dias após a cirurgia.
Purpose: The aim of this study was to evaluate the implant stability through frequency resonance analysis and the effect that different loading time will have on the bone response around implants through a histomorphometric analysis. Material and Methods: Three Replace Select implants were placed on each side of the mandible in 8 dogs totaling 48 implants in the study. One pair of implants was selected for immediate loading protocol (IL). After seven days the second pair of implants received the prostheses for the early loading protocol (EL). In each period, the implant stability measurements were performed by means of resonance frequency. After 12 weeks, a new reading of the implant stability was performed. Fourteen days after the implant placement the third pair of implants received the prostheses for the advanced early loading (AEL). Following a period totaling twelve weeks of prosthetics, the animals were sacrificed and the specimens were prepared for histomorphometric analysis. The differences between loading time in the following parameters: bone-to-implant contact (BIC), bone density (BD) and crestal bone loss (CBL) were evaluated through ANOVA. Results: The mean values of initial stability (ISQ) in different loading times were 77.88 ± 4.61 (IL), 79.73 ± 3.55 (EL) and 79.64 ± 3.00 (AEL). The data were subject to ANOVA and a significant difference was not detected (p = 0.30). The mean values of final stability in different loading times were 80.46 ± 4.23 (IL), 81.88 ± 3.55 (EL) and 81.88 ± 3.42 (AEL). The data were subject to ANOVA and a significant difference was not detected (p = 0.47). To evaluate the implant stability in function of time, a variance analysis for repeated samples was performed, and there was significant difference (p = 0.003), indicating, for each group, a significant increase in stability at the end of the experiment. The time versus method interaction did not show significant difference (p = 0.97), indicating that the variations are similar in the studied groups. The percentage of BIC for IL was 77.9 ± 1.71%, for EL was 79.25 ± 2.11% and for AEL was 79.42 ± 1.49%. The percentage of BD for IL was 69.97 ± 3.81%, for EL was 69.23 ± 5.68% and for AEL was 69.19 ± 2.90%. The CBL for IL was 1.57 ± 0.22mm, for EL was 1.23 ± 0.19mm and for AEL was 1.17 ± 0.32mm. There was no statistical difference for any of the parameters evaluated (p>0.05). Conclusion: Considering primary stability, bone-to-implant contact, bone density around the implants and crestal bone loss, there are no significant differences until 12 weeks after surgery for the stability of immediate, 7 or 14 days after placement activated implants.

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Carlfjord, Caspar, and Elin Hedström. "Long-term Evaluation of Bone Augmentation Procedures with Autogenous Bone or Bone Substitutes in Association with Implant Treatment." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19845.

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Syfte. Syftet med denna systematiska litteraturöversikt var att undersöka det vetenskapliga underlaget avseende långsiktig stabilitet hos olika typer av benersättningsmaterial i kombination med implantatinstallation.Material och metod. En elektronisk sökning gjordes med hjälp av PubMed och Web of Science. Block med sökord konstruerades och skrevs in i sökmotorerna för att hitta studier med implantatbehandling i kombination med benaugmentation, med en radiologisk uppföljning efter minst 2 år. Funna artiklar granskades i förhållande till förutbestämda inklusions- och exklusionskriterier. Data från inkluderade studier registrerades. Risken för bias i de inkluderade studierna bedömdes enligt modifierade protokoll.Resultat. Den elektroniska sökningen resulterade i 1183 studier, varav 14 studier med antingen autogent, allogent, xenogent eller alloplastiskt benersättningsmaterial inkluderades i denna litteraturöversikt. Resultatet från studierna visade en stor skillnad i både tekniker och material.Slutsats. Den generella slutsatsen i denna studie är att den marginella benförlusten vid dentala implantat som placerats i augmenterat ben inte överstiger 1 mm inom två år. En mer exakt slutsats om den marginella bennivåns stabilitet kunde inte dras på grund av de stora skillnaderna mellan de inkluderade studierna. Det finns ett behov av fler högkvalitativa studier med långtidsuppföljning som undersöker och jämför den marginella bennivåns stabilitet för olika benersättningsmaterial.
Aim. The purpose of this systematic review was to investigate the literature available regarding long-term stability of different bone augmentation materials in combination with dental implant treatment.Material and methods. An electronic search was done using PubMed and Web of Science. Blocks with keywords were constructed and inserted into the search engines to find studies involving implant treatment in combination with bone augmentation, with a radiographic follow-up of at least 2 years. Found articles were reviewed in relation to predetermined inclusion- and exclusion criteria. Data from included studies was extracted. Included studies were assessed of risk of bias according to modified protocols. Results. The electronic search yielded 1183 studies. 14 studies using either autogenous, allogeneic, xenogeneic or alloplastic augmentation materials was included in this review. The results from the data extraction process showed a wide variation in both materials and techniques used.Conclusion. The general conclusion drawn from this study is that marginal bone loss around dental implants placed in augmented bone does not exceed 1 mm within two years post-operatively. A more precise conclusion regarding marginal bone level stability could not be drawn due to the heterogeneity of the included studies. There is a need for additional high-quality studies with long-term follow-up, investigating and comparing marginal bone level stability for different bone augmentation materials.

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Mateus, Christiano Pavan. "Avaliação do composto ósseo de Ricinus granulado e hidroxiapatita sintética na osteointegração em coelhos: estudo histológico." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-02092010-104316/.

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Com o crescimento empenho da medicina humana e veterinária na busca de biomateriais osteointegráveis, o estudo histológico se faz presente na interpretação e apresentação por resultados histomorfológicos das interações dos materiais implantados com o tecido ósseo, possibilitando o conhecimento da velocidade de neoformação óssea. A proposta deste trabalho foi avaliar por estudo histológico a bioatividade do composto ósseo de Ricinus granulado e hidroxiapatita sintética, implantados no osso ilíaco de coelhos, possibilitando uma melhor compreensão das interações das interfaces osso/implante, frente aos resultados histomorfológicos, sendo interpretados e apresentados por análise descritiva qualitativa. Foram selecionados 30 coelhos, fêmeas, Oryctolagus cuniculus, grupo geneticamente modificado - Botucatu, idade adulta de 90 dias, peso entre 2,55 e 3,1 Kg divididos em 3 grupos de 10 animais (G1, G2 e G3) sendo que o tempo de pós-operatório foi de G1 com 45 dias, G2 com 70 dias e G3 com 120 dias. Cada animal recebeu 3 defeitos ósseos no osso ilíaco, sendo que dois foram preenchidos pelos biomateriais: hidroxiapatita sintética e composto ósseo de Ricinus granulado e o terceiro para controle. Após a eutanásia, o osso ilíaco foi removido, identificado e submetido ao procedimento histológico. Concluiu-se através da avaliação histológica a crescente modificação da estrutura inicial para a deposição de nova formação óssea, sobressaindo células gigantes de corpo estranho (em alguns casos), fibroblastos e abundante presença de tecido conjuntivo sem diferenciação óssea. E os materiais foram considerados como biocompatíveis e biologicamente ativos.
With the growing commitment of human and veterinary medicine in the search for biomaterials osseointegration, the histological study is present in the interpretation and presentation of results of histomorphologic interactions of materials implanted with bone tissue, providing a speed of bone formation. The proposal was evaluated by histological study the bioactivity of the compound of granulated Ricinus and synthetic hydroxyapatite implanted in rabbit iliac bone, allowing a better understanding of the interactions of bone-implant interface, as compared with histopathologic results, and interpreted and presented by qualitative descriptive analysis. We used 30 female rabbits, Oryctolagus cuniculus, group - Botucatu, adulthood in 90 days, weighing between 2.55 and 3.1 kilograms divided into 3 groups of 10 animals (G1, G2 and G3) and that the length after surgery was 45 days with G1, G2 in 70 days and G3 with 120 days. Each animal received 3 bone defects in the pelvic bone, two of which were completed by biomaterials: synthetic hydroxyapatite and compound of granulated Ricinus and the third for control. After euthanasia, the iliac bone was removed, identified and subjected to histological procedures. It was concluded by the increasing histological modification of the initial structure for the deposition of new bone formation, towering giant cells of foreign body (in some cases), fibroblasts and abundant presence of connective tissue without bone differentiation. And the materials were considered as biocompatible and biologically active.

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Lemo, Vagner Samy [UNESP]. "Avaliação clínica e radiográfica dos tecidos peri-implantares de implantes osseointegrados que receberam carregamento imediato." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/96199.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Um estudo clínico e radiográfico foi realizado para analisar o resultado do tratamento com implantes unitários e unidos (prótese protocolo), instalados e imediatamente carregados. O estudo inclui 10 pacientes que receberam 10 implantes e próteses provisórias unitárias e 5 pacientes que receberam 25 implantes, 5 implantes cada paciente entre os foramens mentoniano, estes foram unidos e receberam uma prótese tipo protocolo. Todas as próteses foram instaladas imediatamente após a cirurgia. Em um intervalo de 6 e 12 meses todos os pacientes foram radiografados e avaliados clinicamente. Não foram registradas perdas no grupo de implantes unitários e o grupo de implantes que recebeu prótese protocolo perdeu 2 implantes. Não houve alterações nos parâmetros periodontais (clínicos e radiográficos) entre os períodos de 6 e 12 meses, e as diferenças encontradas entre os implantes unitários e unidos, parecem estar mais relacionados ao local de inserção (maxila - mandíbula). Podemos concluir que a carga imediata é um procedimento previsível tanto para implantes unitários como em implantes unidos.
The study includes 10 patient that received 10 implants and unitary temporary prostheses and 5 patient that received 25 implants, 5 implants each patient one in the area previous of jawbone, these were united and they received a prosthesis type protocol. All of the prostheses were installed immediately after the surgery. In an interval of 6 and 12 months all the patients were x-rayed and evaluated clinically. Losses were not registered in the group of unitary implants and the group of implants that it received prosthesis protocol lost 2 implants. There were not alterations in the periodontal parameters (clinical and radiographic) among the periods of 6 and 12 months, and the differences found among the unitary and united implants, they seem to be more related to the insert place (jawbone - jaw). We can conclude that the immediate load is a previsible procedure so much for unitary implants as in united implants.

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33

Lekeš, Jonáš. "Výroba dentálních náhrad." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230811.

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Tato práce popisuje části dentálních náhrad, lékařské pojmy, které se s nimi vážou a vysvětluje proces a problematiku koncepce a výroby těchto částí. Různé druhy biomateriálů jako kovy, keramika, polymery či kompozity jsou zde popsány, hlavní důraz je však kladen na titanové a chrom kobaltové slitiny a korozivzdorné oceli. Experimentální část nabízí 2 řešení zlepšení výroby součásti. První část experimentální části se zabývá zlepšením kvality styčné plochy pilíře zvýšením hustoty síťování součásti. Druhá část nabízí nahrazení operace frézování operací vrtání. Byly vybrány nástoje od 4 výrobců. Pro nalezení vhodného nástroje jsou provedeny 2 testy vrtání a vybrán nástroj vhodný pro obrábění titanové a chrom kobaltové slitiny.

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Deco, Camila Porto de. "Influência da osteoporose e álcool na osseointegração de implantes em ratas /." São José dos Campos : [s.n.], 2009. http://hdl.handle.net/11449/87938.

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Orientador: Leonardo Marchini
Banca: Rosilene Fernandes da Rocha
Banca: Célia Marisa Rizzatti Barbosa
Resumo: O consumo de álcool e a osteoporose, individualmente, podem afetar o metabolismo ósseo e ter influência negativa sobre tratamentos com implantes odontológicos, comprometendo sua estabilidade biomecânica. Entretanto, os efeitos da associação entre esses dois fatores na osseointegração de implantes é desconhecido. O objetivo deste trabalho foi investigar parâmetros histomorfométricos da osseointegração em ratas sob consumo de álcool associado à osteoporose. Noventa e seis ratas foram divididas conforme o tipo de dieta e quanto à presença ou ausência hormonal. Grupo G1: Sham (ovariectomia simulada), água e ração ad libitum; G2: Sham, ração e solução de etanol a 20% ad libitum; G3: Sham, ração e solução de sacarose controladas para assegurar uma dieta isocalórica à de G2; G4: ovariectomia, água e ração ad libitum; G5: ovariectomia, ração e solução de etanol a 20% ad libitum; G6: ovariectomia, ração e solução de sacarose controladas para assegurar uma dieta isocalórica à de G5. Cada grupo foi subdividido em A e B, de acordo com o tempo de osseointegração: 4 ou 6 semanas, respectivamente. Um mês após a ovariectomia ou Sham foi iniciada a dieta e um mês depois foi realizada a cirurgia para colocação dos implantes de titânio nos fêmures dos animais. Após a eutanásia, os fêmures foram avaliados por histomorfometria para quantificação da superfície de contato direto entre osso e implante. Os grupos G5 e G6 foram os que apresentaram a menor porcentagem de contato direto ossoimplante quando comparados aos demais. Conclusão: A associação entre a deficiência estrogênica, provocada pela ovariectomia, e o consumo crônico de álcool pode prejudicar a osseointegração, assim como a associação entre deficiência estrogênica e redução no consumo de nutrientes.
Abstract: Alcohol intake and osteoporosis can, separately, affect bone physiology and have presented negative impacts on dental implant therapy. However, the effects of the association of both factors in the osseointegration are unknown. The aim of this study was evaluate osseointegration in rats alcohol fed and presenting induced osteoporosis. Methodology: Ninety-six female rats were divided according to diet and hormonal condition. Group G1: Sham (simulated ovariectomy), food and water ad libitum; G2: Sham, food and ethanol 20% solution ad libitum; G3: Sham, food and sucrose solution controlled to warranty an isocaloric diet in relation to G2; G4 ovariectomy, food and water ad libitum; G5 ovariectomy, food and ethanol 20% solution ad libitum; G6: ovariectomy, food and sucrose solution controlled to warranty an isocaloric diet to G5. The groups were subdivided according to time of osseointegration 4 or 6 weeks. Implants surgery was done one month after ovariectomy or Sham. After euthanasia, the femurs were removed and evaluated by histomorfometry. Results: Groups G5 and G6 showed the worse osseointegration condition. Conclusion: The association between estrogen deficiency and alcohol intake and the association between estrogen deficiency and reduced intake of nutrients can negatively affect osseointegration.
Mestre

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35

Magnusson, Emelie. "FE analysis and design of the mechanical connection in an osseointegrated prosthesis system." Thesis, Linköpings universitet, Mekanik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69402.

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In this master thesis the connection between the two major parts of an osseointegrated prosthesis system for lower limb amputees has been investigated by finite element (FE) analysis. The prosthesis system is developed by Integrum and the current design consists of a fixture, which is integrated in the residual bone, an abutment that penetrates the skin and an abutment screw that holds the parts together. The connection between the fixture and the abutment has a hexagonal section and a press-fit section that together form the connection. Due to wear and fracture problems it is desired to improve the connection. A tapered connection could be an alternative and three different taper angles, the effect of the length of the taper and the smoothness of the outer edge of a tapered fixture have been investigated. The results show that the taper has potential to function well and that a longer connection will give lower stresses in the system, but further investigations are needed.

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Lemo, Vagner Samy. "Avaliação clínica e radiográfica dos tecidos peri-implantares de implantes osseointegrados que receberam carregamento imediato /." Araraquara : [s.n.], 2004. http://hdl.handle.net/11449/96199.

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Resumo: Um estudo clínico e radiográfico foi realizado para analisar o resultado do tratamento com implantes unitários e unidos (prótese protocolo), instalados e imediatamente carregados. O estudo inclui 10 pacientes que receberam 10 implantes e próteses provisórias unitárias e 5 pacientes que receberam 25 implantes, 5 implantes cada paciente entre os foramens mentoniano, estes foram unidos e receberam uma prótese tipo protocolo. Todas as próteses foram instaladas imediatamente após a cirurgia. Em um intervalo de 6 e 12 meses todos os pacientes foram radiografados e avaliados clinicamente. Não foram registradas perdas no grupo de implantes unitários e o grupo de implantes que recebeu prótese protocolo perdeu 2 implantes. Não houve alterações nos parâmetros periodontais (clínicos e radiográficos) entre os períodos de 6 e 12 meses, e as diferenças encontradas entre os implantes unitários e unidos, parecem estar mais relacionados ao local de inserção (maxila - mandíbula). Podemos concluir que a carga imediata é um procedimento previsível tanto para implantes unitários como em implantes unidos.
Abstract: The study includes 10 patient that received 10 implants and unitary temporary prostheses and 5 patient that received 25 implants, 5 implants each patient one in the area previous of jawbone, these were united and they received a prosthesis type protocol. All of the prostheses were installed immediately after the surgery. In an interval of 6 and 12 months all the patients were x-rayed and evaluated clinically. Losses were not registered in the group of unitary implants and the group of implants that it received prosthesis protocol lost 2 implants. There were not alterations in the periodontal parameters (clinical and radiographic) among the periods of 6 and 12 months, and the differences found among the unitary and united implants, they seem to be more related to the insert place (jawbone - jaw). We can conclude that the immediate load is a previsible procedure so much for unitary implants as in united implants.
Orientador: Elcio Marcantonio
Coorientador: Elcio Marcantonio Junior
Banca: Roberto Henrique Barbeiro
Banca: Wilson Trevisan Junior
Mestre

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37

Piskounova, Sonya. "Biomaterials for Promoting Self-Healing of Bone Tissue." Doctoral thesis, Uppsala universitet, Polymerkemi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-158939.

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The present work addresses poor bone/implant integration and severe bone defects. In both conditions external stimuli is required for new bone to form. A multilayered functional implant coating, comprised of an inner layer of crystalline titanium dioxide (TiO2) and an outer layer of hydroxyapatite (HAP), loaded with bone morphogenetic protein-2 (BMP-2), was proposed as a tool for providing both improved initial bone formation and long-term osseointegration. The in vitro characterization of the implant coatings showed that TiO2 and HAP were more favorable for cell viability, cell morphology and initial cell differentiation, compared to native titanium oxide. Furthermore, significantly higher cell differentiation was observed on surfaces with BMP-2, indicating that a simple soaking process can be used for incorporating bioactive molecules. Moreover, the results suggest that there could be a direct interaction between BMP-2 and HAP, which prolongs the retention of the growth factor, improving its therapeutic effect. For treating severe bone defects a strategy involving BMP-2 delivery from hyaluronan hydrogels was explored. The hydrogels were prepared from two reactive polymers – an aldehyde-modified hyaluronan and a hydrazide-modified poly(vinyl alcohol). Upon mixing, the two components formed a chemically crosslinked hydrogel. In this work the mixing of the hydrogel components was optimized by rheological measurements. Furthermore, an appropriate buffer was selected for in vitro experiments by studying the swelling of hydrogels in PBS and in cell culture medium. A detection method, based on radioactive labeling of BMP-2 with 125I was used to monitor growth factor release both in vitro and in vivo. The results showed a biphasic release profile of BMP-2, where approximately 16 % and 3 % of the growth factor remained inside the hydrogel after 4 weeks in vitro and in vivo, respectively. The initial fast release phase corresponded to the early ectopic bone formation observed 8 d after injection of the hydrogel formulation in the thigh muscle of rats. The hydrogel formulation could be improved by incorporation of HAP powder into the hydrogel formulation. Furthermore, bone formation could be increased by pre-incubation of the premixed hydrogel components inside the syringe prior to injection. Crushed hydrogels were also observed to induce more bone formation compared to solid hydrogels, when implanted subcutaneously in rats. This was thought to be due to increased surface area of the hydrogel, which allowed for improved cell infiltration.

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Зеленська, Н. В. "Морфо-функціональні особливості кістки при введенні металевих імплантантів різного складу." Thesis, Сумський державний університет, 2017. http://essuir.sumdu.edu.ua/handle/123456789/50910.

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Дисертація присвячена вивченню морфофункціональних особливостей процесів остеоінтеграції металевих імплантатів різного складу та процесів перебудови віддалених ділянок кістки в різні терміни після імплантації. Вперше встановлені зміни в різних ділянках стегнової кістки при імплантації сплавів різного складу. Встановлені особливості процесів остеоінтеграції в залежності від виду сплаву та наявності гідроксиапатитного покриття. Доведені структурні зміни діафізу та дистального епіфізу в ранні та віддалені періоди після імплантації металевих простезів та прослідковані особливості змін в залежності від типу імплантату. В роботі визначені зміни хімічного складу у віддалених ділянках кістки, які викликані процесами дифузії складових компонентів імплантату та встановлений факт зменшення вивільнення елементів за умов нанесення гідроксиапатитного напилення на поверхню імплантатів. Використання гідроксиапатиту в якості покриття металевих імплантатів створює оптимальні умови для адгезії клітин на поверхні простезу та стимулює розвиток кісткової тканини, що забезпечує його оптимальну фіксацію. Визначені особливості показників мікротвердості кісткової тканини в різних ділянках органу в залежності від типу імплантату та встановлена можливість зменшення втрати міцності кістки при використанні гідроксиапатитного покриття.
Диссертация посвящена изучению морфофункциональных особенностей процессов остеоинтеграции металлических имплантатов различного состава и процессов перестройки отдаленных участков кости в разные сроки после имплантации. Впервые установлены изменения в различных участках бедренной кости при имплантации сплавов различного состава. Установлены особенности процессов остеоинтеграции в зависимости от вида сплава и наличии гидроксиапатитного покрытия. Доказаны структурные изменения диафиза и дистального епифиза в ранние и отдаленные периоды после имплантации металлических простезов и прослежены особенности изменений в зависимости от типа имплантата. В работе определены изменения химического состава в отдаленных участках кости, вызванные процессами диффузии составляющих компонентов имплантата и установлен факт уменьшения высвобождения элементов в условиях нанесения гидроксиапатитного напыления на поверхность имплантатов. Использование гидроксиапатита в качестве покрытия металлических имплантатов создает оптимальные условия для адгезии клеток на поверхности простеза и стимулирует развитие костной ткани, обеспечивает его оптимальную фиксацию. Определены особенности показателей микротвердости костной ткани в различных участках органа в зависимости от типа имплантата и установлена возможность уменьшения потери прочности кости при использовании гидроксиапатитного покрытия.
Dissertation is devoted to the study of morphological and functional features of the osseointegration of metal implants of various compositions and processes of bone remodeling at different times after the implantation. We indicate the changes in various parts of the femur after implantation of alloys of different compositions. The features of osteointegration processes depending on the type of alloy and the presence of a hydroxyapatite coating. We proved the structural changes in diaphysis and distal epiphisis in early and late periods after implantation of metal prostheses and features depending on the type of implant. We identified a change in chemical composition in different parts of the bones that caused by diffusion of components of implants, and indicated the fact of reducing the release of elements in a hydroxyapatite coating deposition on the surface of the implant. Implantation of TiVT6 alloy in distal epiphysis leads to the formation of woven bone around prosthesis and small amount of connective tissue and activation of remodeling both in periimplant area and in other parts of bone. After the implantation of KTC alloy we can observed same features of bone remodeling as well as micro-fracture of bone tissue distant from implant. β-(Ti-Zr) alloy with low Young Module leads of cortical bone formation in 3 month after implantation and mild morphological, chemical and biomechanical changes in all terms of observation. The use of hydroxyapatite as the coating of metal implants creates optimal conditions for cell adhesion on the prosthesis surface and stimulates bone growth, ensuring its optimal fixation. Optimization of osseointegration leads to lower remodeling activity, including reducing the number of Remodeling units to 3,3 ± 0,1 (p = 0.042) compared with alloys without coating and prevents the loss of calcium and bone microhardness. β-(Ti-Zr) alloy with hydroxyapatite coating prevent ‘stress-shielding’ effect and development of bone microdamages. The chemical composition of bone after the implantation of metal prosthesis characterized by loss of calcium and phosphorus in all parts of the bone. The higher difference from the control is observed for TiVT6 alloy implant - up to 35.89% (p=0.0082) and 24.58% (p=0.017), respectively, and maintained until the end of observation. Activating the bone cells around the implant caused the implant electrochemical erosion and release of ions that appear in periimplant zone and in distant areas of bone in an amount from 0.4 to 2.7% weight %. Coating the implants reduces the loss of calcium to 7.5% (p=0.045) and reduced the release of elements of implant and their migration to surrounding tissues and distant sites. We indicate the features of bone microhardness in different areas depending on the type of the implant and indicate reduce of bone strength loss using a hydroxyapatite coating.

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Oliveira, Sérgio Ricardo de [UNESP]. "Estudo da influência de corticóides no processo inicial de osseointegração de implantes de titânio instalados em maxilas de ratos." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/104710.

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As modalidades terapêuticas que envolvem implantes dentais têm se expandido gradativamente, sendo implantados em uma variedade de estruturas ósseas. Dessa forma, o propósito do presente trabalho foi estudar a influência de corticóides no processo inicial de osseointegração de implantes de titânio instalados em maxilas de ratos. Foram utilizados implantes de titânio c.p., grau II, cônico de 1,4mm de diâmetro e 2,7mm de comprimento, com superfície tratada. Trinta e oito ratos wistar tiveram seus primeiros molares superiores esquerdo e direito extraídos. Após 30 dias de reparo alveolar, dois animais foram sacrificados para confirmar o fim desse processo. Os demais animais tiveram os implantes instalados bilateralmente e foram divididos randomicamente em três grupos: Controle (Ctr/n=12) que não receberam nenhum tipo de tratamento; Placebo (Pl/n=12) e Tratado (Tra/n=12), que receberam injeções diárias de 1 ml de solução salina e corticosterona na dosagem de 5mg/kg, respectivamente. Trinta dias após a implantação, todos os animais foram eutanasiados e tiveram a concentração plasmática do corticóide mensurada: Ctr (101,31 ± 26,7 ng/ml), Pla (95,22 ± 25,36 ng/ml) e Tra (281,37 ± 64,72 ng/ml); e o contato osso-implante determinado: Ctr (96,67%), Pla (82,22%) e Tra (15,73%), nos quais o grupo Tra apresentou-se estatisticamente diferente dos demais grupos (p<0,05). Assim, diante da metodologia empregada, foram evidenciadas menor formação óssea e conseqüente redução da área de tecido ósseo neo-formado na interface osso-implante.
The therapeutic modalities which involves dental implants has been gradually expanded, being implanted in a variety of bone structures. In this way, the aim of the present work was to study the corticoid influence at the initial process of bone integration of titanium implants installed in rat jaws. It were used titanium implants c.p.; grade II, conic with 1,4mm diameter and 2,7mm length, with treated surface. Thirty eight wistar rats had their first upper left and right molars extracted. After 30 days of alveolar repair, two animals were sacrificed to confirm the end of this process. The others had their implants installed bilaterally and they were splited randomly in three groups: Control (Ctr/n=12) which did not receive any kind of treatment; Placebo (Pla/n=12) and Treated (Tre/n=12) which received 1ml daily shots of salt solution and corticosterone at a dosage of 5mg/Kg, respectively. Thirty days after the implantation, all the animals were euthanasiated and the plasmatic concentration of corticoid was measured: Ctr (101,31 ± 26,7 ng/ml), Pla (95,22 ± 25,36 ng/ml) and Tre (281,37 ± 64,72 ng/ml); and the bone implant contact was determined: Ctr (96,67%), Pla (82,22%) and Tre (15,73%), in which the Tre group presented statistically different from the other groups (p<0,05). Thus, front the employed methodology it was shown lesser bone formation and consequent reduction of the bone tissue area neo-formed at bone-implant interface.

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Carvalho, Lais Morandini. "Análise in vivo da modulação óssea em implantes de titânio com superfície em nanoescala." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152408.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Nas últimas décadas houve um aumento considerável na utilização dos implantes metálicos para aplicações na área da ortopedia e odontologia, por isso as pesquisas têm como foco estudar os mecanismos biológicos de interação osso-implante. A nanotopografia de superfície de implantes osseointegráveis apresenta efeito direto sobre a resposta biológica óssea. No entanto a maneira como afeta a osseointegração in vivo ainda não está totalmente elucidada. O objetivo neste estudo foi comparar in vivo a influência da superfície em nanoescala (nano) confeccionada em implantes de titânio comercialmente puro (Ticp), comparado-a a superfície lisa (controle) em modelo experimental de camundongos osterix-mcherry (Osx-mcherry), os quais expressam proteína fluorescente concomitante com a expressão do gene osterix (Osx). Os animais receberam implantes de superfície lisa no fêmur direito e com nanoescala no fêmur esquerdo. Após diferentes períodos de eutanásia baseados na metodologia empregada foram realizados nas peças e nas células os seguintes testes biológicos: microscopia eletrônica de varredura (MEV) para avaliação da adesão celular e da superfície do implante; histologia e nanotomografia (nanoCT) para observação e quantificação de osso neoformado na interface osso/implante; citometria de fluxo para quantificação de células marcadas pelo gene osterix; PCR em tempo real (qPCR) para avaliação da expressão gênica; coloração fosfatase ácida resistente ao tartarato (TRAP) para contagem de osteoclastos. Nossos resultados mostraram que a maioria dos genes estudados estavam superexpressos nas amostras com superfície em nanoescala sendo que alguns deles apresentaram diferenças estatísticas (Teste t, p < 0.05), tais como: Osx (osterix), Alp (fosfatase alcalina), Prx1(homeobox relacionado emparelhado -1), Dmp1 (Dolicol-fosfatase mannosiltransferase subunidade 1), Bsp (sialoproteína óssea) e Ocn (osteocalcina). Os testes estatísticos ANOVA two way seguido do Teste de Tukey quando necessário, foram utilizados para os demais experimentos e o nível de significância foi estabelecido em p < 0.05. Diferenças estatísticas foram encontradas para o nanoCT e histologia entre as superfícies e períodos avaliados e os melhores resultados foram observados para a nanoescala. A coloração TRAP também mostrou diferenças estatísticas entre as superfícies e períodos estudados, com a superfície lisa mostrando melhores resultados aos 3 dias e a nano aos 5 e 7 dias. Não houve diferença estatística para a citometria de fluxo, porém a superfície em nanoescala mostrou melhores resultados que a lisa em todos os períodos analisados. Concluímos que a superfície em nanoescala possui propriedades osteocondutivas e favorece os eventos biológicos que ocorrem na superfície do implante melhorando o processo de osseointegração.

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Sverzut, Alexander Tadeu 1975. "Estudo da perda precoce de implantes osseointegraveis realizados na Faculdade de Odontologia de Piracicaba - Unicamp no periodo de julho de 1996 a julho de 2004." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288777.

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Orientador: Roger William Fernandes Moreira
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: As perdas de implantes dentários podem ser classificadas em precoces ou tardias segundo BUSER et al. (1991). Esse trabalho objetivou analisar a perda precoce de implantes dentários e os fatores de risco associados. Foram utilizados para análise os prontuários clínicos dos pacientes tratados pela Área de Cirurgia Buco-Maxilo-Facial da Faculdade de Odontologia de Piracicaba-Unicamp que foram submetidos à instalação de implantes dentários no período de julho de 1996 a julho de 2004. Foram selecionados pacientes submetidos à instalação de implantes osseointegráveis e que foram submetidos à segunda fase cirúrgica. As variáveis selecionadas para o estudo foram: gênero, idade, uso do tabaco, uso do álcool, protocolo de instalação de implantes, reconstruções prévias, comprimento do implante, diâmetro do implante, área de instalação do implante, tipo de superfície do implante, uso de contraceptivos orais, terapia de reposição hormonal, hipertensão arterial, hipotireoidismo, hipertireoidismo e diabetes. Foram catalogados 1403 prontuários sendo que 660 prontuários efetivamente foram utilizados no estudo. Foram instalados e analisados 1649 implantes, 62 destes sofreram perda precoce. Os dados coletados foram analisados através de estatística univariada e regressão logística multivariada, demonstrando a significância e o fator de risco quanto à perda precoce de implantes dentários. De acordo com a metodologia empregada a conclusão do estudo foi que a infecção precoce é o maior fator de risco relacionado à perda precoce de implantes dentários, aumentando em 44 vezes chance de falha relacionadas a implantes que não apresentaram nenhum tipo de infecção, implantes curtos 6-9mm exibem um fator de risco quanto à perda precoce 4 vezes maiores que implantes com comprimentos maiores e processos reconstrutivos prévios, condições sistêmicas, vícios, gênero, idade, não influenciam a perda precoce de implantes
Abstract: Dental implant failures can be classified in early or delayed, according to BUSER et al. (1991). The purpose of this study was to evaluate the risk factors related to early loss of dental implants. The clinical files of all patients subjected to the installation of dental implants in the Oral and Maxillofacial area, Piracicaba Dental School, State University of Campinas, in the period from 1996 to 2004, were analyzed. The inclusion criterion was the installation of dental implants in patients that had been subjected to the second surgical phase. The selected variables were: gender, age, tobacco use, alcohol use, implant installation protocol, previous reconstructive procedures, implant length, implant width, area of installation of the implants, implant surface, hormonal contraceptive use, hormone reposition therapy, arterial hypertension, hypothyroidism, hyperthyroidism and diabetes. A total of 1403 files were evaluated and 660 could be used in the study. A number of 1649 implants were installed and analyzed, and 62 of them had suffered early loss. The collected data were analyzed through univariate statistics and multivariate logistic regression, showing the significance and risk factors for early loss of dental implants. According to the employed methodology, it could be concluded that early infection is the main factor of risk related to early dental implant loss, increasing in 44 times the failure possibility when compared to implants without any type of infection; short implants (6-9mm) increase the risk of early implant loss in 4 times. Narrow implants presented significance for early loss, but are not considered risk factors. Previous reconstructive procedures, systemic conditions, addictions, gender and age did not present statistical significance and are not risk factors for early loss of dental implants
Mestrado
Cirurgia e Traumatologia Buco-Maxilo-Faciais
Mestre em Clínica Odontológica

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Senna, Plinio Mendes 1984. "Analyzes of the surface integrity of dental implants and the influence of nitriding and amino-functionalization treatments on osteogenesis = Análises da integridade da superfície de implantes dentais e da influência dos tratamentos de nitretação e amino-funcionalização na osteogênese." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287990.

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Orientador: Altair Antoninha Del Bel Cury
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Os implantes dentais recebem diversos tratamentos para criar micro- e nano-estruturas na superfície, aumentando a área de contato com o osso e favorecendo a osseointegração. O objetivo deste trabalho foi quantificar por meio de parâmetros de rugosidade as alterações de superfície causadas pelo processo de inserção no tecido ósseo e investigar a presença de partículas soltas de titânio na interface osso-implante (Capítulo 1); avaliar a influência do tratamento de nitretação por plasma nas propriedades de superfície do titânio e na sua biocompatibilidade (Capítulo 2); e avaliar a adsorção de proteínas in vitro e a osteogênese ao redor de implantes amino-funcionalizados instalados em coelhos (Capítulo 3). No Capítulo 1, a rugosidade de três grupos de implantes representando differences geometrias e tratamentos de superfície foi avaliada por interferometria antes e após a inserção dos mesmos em blocos de costela bovina. Os blocos também foram avaliados por microscopia para identificar partículas de titânio presentes na interface. A amplitude de todos os parâmetros de rugosidade das superfícies dos implantes foram menores após a inserção para todos os grupos e as imagens microscópicas revelaram a presença de partículas de titânio a alumínio na interface, concentradas principalmente no nível do osso cortical. Assim, concluiu-se que as superfícies moderadamente rugosas podem gerar partículas soltas de titânio na interface. No Capítulo 2, discos de titânio (12,7 × 2 mm) moderadamente rugosos foram nitretados por plasma a frio. Osteoblastos humanos (SAOS-2) foram cultivados sobre os discos por 1, 3, 5 e 7 dias. A proliferação e diferenciação celular foram avaliadas por MTS, produção de fosfatase alcalina e por qPCR. Foi observado, que a nitretação aumentou a quantidade de nitrogênio na superfície, além da dureza, molhabilidade e nanoestruturas. Não houve diferença no comportamento célular em relação ao grupo não nitretado. Assim, concluiu-se que a nitretação por plasma a frio aumentou a dureza da superfície e não prejudicou a biocompatibilidade do titânio. No Capítulo 3, o titânio foi aminofuncionalizado com 3-aminopropiltrietoxisilano. O perfil protéico adsorvido foi avaliado por espectrometria de massas após discos serem imersos em plasma sanguíneo humano por 3 h. Para a análise da osteogênese, implantes de titânio (3,75 × 6 mm) receberam o mesmo tratamento e foram instalados em 10 coelhos New Zealand adultos (1 na metáfise distal do fêmur e 2 na metáfise proximal da tíbia de ambas as patas). Os animais foram sacrificados após 3 e 6 semanas e os implantes e osso adjacente foram coletados, fixados e incluídos em blocos de resina. Em seguida, lâminas de 20 ?m de espessura foram preparadas na região central de cada implante e coradas com azul de toluidina. A análise histomorfométrica compreendeu a mensuração da área de contato osso-implante. A superfície tratada apresentou maior quantidade total de proteínas adsorvidas; no entanto, com menor abundância relativa de fibronectina. Não houve diferença para a área de contato osso-implante entre os dois grupos de implantes após 3 e 6 semanas. Assim, concluiu-se que a amino-funcionalização aumentou a quantidade de proteínas adsorvidas, mas não foi efetiva para acelerar a osteogênese.
Abstract: Dental implants receive surface treatments to create micro- and nanostructures on surface to increase the contacting area with bone, which favors osseointegration. However, the resistance of these structures in face of the friction against the bone tissue during the implant insertion is not evaluated yet. Thus, the objective in this study was to quantify by means of roughness parameters the surface wear caused by the insertion procedure in the bone tissue and to investigate the presence of loose titanium particles at bone-implant interface (Chapter 1); to evaluate the influence of plasma nitriding treatment on surface properties of titanium and on its biocompatibility (Chapter 2); and to investigate the protein adsorption in vitro and osteogenesis around amino-functionalized implants placed in rabbits (Chapter 3). In Chapter 1, roughness of three implants representing different geometries and surface treatments were evaluated by interferometry before and after insertion into bovine rib blocks. The blocks were also evaluated by microscopy to identify titanium particles at the interface. The amplitude of all roughness parameters were smaller after the insertion procedure for all implant groups and microscopic images revealed presence of loose titanium and aluminum particles at the interface, concentrated at the cortical crest. Therefore, it was concluded that moderately rough surfaces can release loose particles at the interface. In Chapter 2, titanium discs (12.7 × 2 mm) with moderately rough surface were nitrided by cold plasma. Human osteoblasts (SAOS-2) were cultivated on the discs for 1, 3, 5 and 7 days. Cell proliferation and differentiation were evaluated by MTS, production of alkaline phosphatase and by qPCR. It was observed that plasma nitriding increased the nitrogen content on surface, and also hardness, wettability and nanostructures. No significant difference between titanium and nitrided surface was seen on cell behavior. Therefore, it was concluded that nitriding treatment increase surface hardness and does not jeopardize the biocompatibility of titanium. In Chapter 3, titanium was amino-functionalized by 3-aminopropyltriethoxysilane. Protein profile was identified by mass spectroscopy after discs were immersed in human blood plasma for 3 h. To evaluate osteogenesis, titanium implants (3.75 × 6 mm) were placed in 10 New Zealand adult rabbits (1 in the femoral distal metaphysis and 2 in the tibial proximal metaphysis of both legs). The animals were sacrificed after 3 and 6 weeks and implants with adjacent bone were collected, fixed and included in resin blocks. After, 20 ?m thick slides were prepared at the central region of each implant and stained by toluidine blue. Histomorphometric analysis consisted of measuring the bone-to-implant contact (BIC). Treated surface exhibited higher amount of adsorbed proteins; however, lower relative abundance of fibronectin. No significant difference was identified between the groups for BIC values after 3 and 6 weeks. Therefore, amino-functionalization enhance protein adsorption but has no effect on early bone formation.
Doutorado
Protese Dental
Doutor em Clínica Odontológica

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Andrade, Dennia Perez de. "Biocompatibilidade in vitro em amostras densas e porosas de titânio-35nióbio submetidas a tratamento biomimético /." São José dos Campos : [s.n.], 2011. http://hdl.handle.net/11449/104658.

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Resumo: Titânio (Ti) é um dos melhores biomateriais para a confecção de implantes cirúrgicos, porém, estudos com novas ligas de Ti e variações da topografia visam otimizar os resultados da osseointegração. O objetivo deste estudo in vitro foi avaliar a biocompatibilidade de amostras densas e porosas da liga titânio- 35nióbio submetidas ou não ao tratamento biomimético, comparadas a amostras de Ti puro grau 2. As amostras foram divididas em 6 grupos (G): a) G1- Ti denso; b) G2 - Ti poroso; c) G3 - Ti poroso tratado; d) G4 - Ti-35Nb denso; e) G5 - Ti-35Nb poroso; f) G6 - Ti-35Nb poroso tratado. Células osteogênicas obtidas da calvária de ratos recémnascidos foram plaqueadas sobre as amostras e a adesão celular foi avaliada após 4 e 24 horas, enquanto a proliferação celular foi avaliada em 1, 3, 7 e 10 dias. A viabilidade foi avaliada em 1, 3, 7 e 10 dias. Para os demais testes as células foram cultivadas por 7, 10 e 14 dias. Após 14 dias, as culturas foram coradas com vermelho de Alizarina S para detecção dos nódulos de mineralização. As amostras foram caracterizadas por espectroscopia por dispersão de energia (EDS), difração de raio X (DRX), análise metalográfica e de rugosidade. Os dados da análise metalográfica foram submetidos ao teste de Kruskal Wallis e os dados das análises celulares foram comparados pelos testes Kruskal Wallis, Mann-Whitney e T-Student, (p<0,05). O EDS demonstrou a presença de íons sódio, fósforo, magnésio e cálcio nas amostras tratadas de ambos os grupos. O DRX demonstrou a presença dos metais titânio e nióbio na liga teste. A análise metalográfica demonstrou que as amostras porosas apresentavam poros interligados, com morfologia variada e a análise pelo rugosímetro demonstrou... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Titanium (Ti) is one of the best biomaterials for surgical implants fabrication. Studies with new titanium alloys and varied surface topographies seek for improved osseointegration results. The aim of the present in vitro study was to evaluate dense and porous titanium- 35 niobium alloys, submitted or not to biomimetic treatment in comparison to degree 2 pure titanium specimens. Specimens were divided into 6 groups (G): a) G1 - dense Ti; b) G2 - porous Ti; c) G3 - treated porous Ti; d) G4 - dense Ti-35Nb; e) G5 - porous Ti-35Nb and f) G6 - treated porous Ti-35Nb. Osteogenic cells from newborn rats calvarium were plated over the samples and cell adhesion assessed after 4 and 24 hours. Cell proliferation and viability were assessed at 1, 3, 7 and 10 days. Cells were cultured for 7, 10 and 14 days for further testings. Cell cultures were stained with Alizarin Red S after 14 days for mineralization nodules detection. Specimens were characterized by means of Energy Dispersion Spectrophotometry (EDS), X-Ray Diffraction (XRD), metallographic and profilometer analyses. Metallographic data were submitted to Kruskal Wallis, while cell analyses were assessed with Kruskal Wallis, Mann-Whitney and T-Student tests (P<0.05). EDS results detected the presence of sodium, phosphor, magnesium and calcium ions in treated specimens from both groups. XRD showed the presence of titanium and niobium for the test alloy. Metallographic analysis revealed interconnected pores and varied morphology within the porous specimens. Greater rugosity was detected by the profilometer analysis within the dense alloy specimens. In vitro tests revealed similar biocompatibility of Ti- 35Nb and degree 2 pure Ti. Porosity did not interfere, but in some scenarios improved alloy biocompatibility. The biomimetic treatment favor greater production... (Complete abstract click electronic access below)
Orientador: Yasmin Rodarte Carvalho
Coorientador: Carlos Alberto Alves Cairo
Banca: Débora Pallos
Banca: Adriana Aigotti Haberbeck Brandão
Banca: Renata Falchete do Prado
Banca: Maria Aparecida Neves Jardini
Doutor

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Bonsignore, Lindsay Ann. "SURFACE CONTAMINANTS INHIBIT THE OSSEOINTEGRATION OF ORTHOPAEDIC IMPLANTS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1341323221.

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Souza, Francisley Ávila [UNESP]. "Estudo comparativo in vivo de implantes Ti-cp com superfícies comerciais e modificadas por laser sem e com depósito de sílica: análises biomecânica, topográfica e histomorfométrica." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/101052.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Proposição: O objetivo deste estudo foi comparar o comportamento biológico e mecânico do tecido ósseo ao redor de implantes de superfícies comerciais modificada por condicionamento ácido (SA), e usinada (SU), com implantes de superfícies experimentais modificada por laser (SL), e modificada por laser com depósito de sílica (SS), empregando-se as análises biomecânica, topográfica e histométrica. Material e Métodos: Trinta coelhos receberam 120 implantes de 3,75x10mm em suas tíbias direita e esquerda, sendo dois implantes de cada superfície por tíbia. O implante localizado mais superior, instalado na metáfise tibial foi utilizado para o ensaio biomecânico, descrito no capítulo I; e o implante localizado abaixo deste, instalado na epífise tibial foi utilizado para o estudo histométrico, descrito no capítulo II. A morfologia das superfícies dos implantes foi analisada por microscopia eletrônica de varredura (MEV), e por espectroscopia de energia dispersiva de raios X (EDS) antes, e após 4 semanas de implantação e remoção por torque reverso. Medidas de rugosidade e secção transversal foram obtidas. Após períodos de 4, 8, e 12 semanas realizou-se o ensaio biomecânico, e após os animais sofreram eutanásia. As peças do implante localizado na epífise tibial foram levadas ao micrótomo para corte sem descalcificação. A análise histométrica foi realizada empregando-se microscopia óptica. Foi mensurada a extensão linear de contato entre osso e implante (ELCOI), e a área óssea (AO). Uma lâmina de cada superfície do período de 4 semanas foi metalizada para realização da análise do mapeamento elementar por MEV-EDS. Resultados: A caracterização topográfica mostrou diferenças entre as superfícies analisadas, e os valores de rugosidade média das SL e SS foram estatisticamente superiores (p<0,05) a SA. Na comparação estatística dos valores obtidos...
Purpose: The aim of this study was to compare the biologic and mechanical behavior of bone tissue around implants with commercially available surfaces, modified by acid etching (SA), and machined surfaces (SU), with the experimental surfaces modified by laser (SL), and modified by laser with silica deposition (SS), using biomechanical, topographic and histometric analyses. Materials and Methods: Thirty rabbits received 120 implants measuring 3,75x10mm in their right and left tibias, being two implants of each type of surface per tibia. The implant located in the uppermost position, inserted in the tibial metaphysis, was used for the biomechanical test, described in Chapter I; and the implant located below this, inserted in the tibial epiphysis, was used for the histometric study, described in Chapter II. The morphology of the implant surfaces was analyzed by scanning electron microscopy (SEM) and by energy dispersive X-ray spectrometry (EDS) before and after 4 weeks of implantation and removal by reverse torque. Mean roughness and cross-sectional measurements were obtained. After periods of 4, 8, and 12 weeks the biomechanical test was performed, and after this the animals were euthanized. The parts of the implant located in the tibial epiphysis were taken for cutting nondecalcified on a microtome. Histometric analysis was performed using an optical microscope. The bone interface contact (BIC), and the bone area (AO) were measured in percentages. A slide of each surface in the period of 4 weeks was metalized in order to analyze the element mapping by means of SEM-EDS. Results: The topographic characterization showed differences between the analyzed surfaces, and the mean roughness values of SL and SS were statistically higher (p<0,05) than those of SA. In the statistical comparison of the values obtained by the biomechanical test, it was... (Complete abstract click electronic access below)

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Zanicotti, Roberta Targa Stramandinoli. "Avaliação da interface osso- implante em mandíbula de miniporcos irradiados e o uso de células-tronco mesenquimais associadas ao plasma rico em plaquetas na osseointegração." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5155/tde-27022014-093927/.

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Introdução: Pacientes com câncer na região de cabeça e pescoço normalmente são tratados por combinação de cirurgia, radioterapia (RT) e quimioterapia. Em muitos casos, a reabilitação oral com próteses implanto-suportadas representa a melhor opção para uma recuperação funcional adequada. Entretanto, em pacientes irradiados procedimentos como exodontias e instalações de implantes dentários são fatores de risco ao desenvolvimento de osteorradionecrose. Diversos estudos experimentais têm demonstrado que o uso de células-tronco mesenquimais (CTMs) associadas a fatores de crescimento como plasma rico em plaquetas (PRP) proporciona melhora no reparo ósseo e na osseointegração, podendo ser considerada uma alternativa viável para defeitos ósseos ou injúria. Objetivos: Isolar e caracterizar as CTMs da medula óssea (MO) de miniporcos brasileiros (Minipigs BR-1), avaliar a interferência da RT e o efeito da associação de CTMs-MO+PRP no processo de osseointegração de implantes instalados em alvéolos frescos em mandíbulas de miniporcos, por análise histológica e histomorfométrica da interface osso-implante. Métodos: CTMs-MO de 12 miniporcos adultos machos foram isoladas da crista ilíaca. Após 21 dias de cultura, o potencial de diferenciação celular foi avaliado por meio de coloração e RT-PCR. O perfil imunofenotípico foi caracterizado por citometria de fluxo. Os animais foram divididos em três grupos: Grupo A (grupo controle, sem RT), Grupo B (implantes instalados 15 dias antes da RT) e Grupo C (implantes instalados três meses após a RT). A dose total de radiação para cada lado da mandíbula foi de 24 Gy, divididos em três doses de 8 Gy com intervalo de 7 dias entre as doses, a qual equivale biologicamente a aproximadamente 56 Gy, com 28 exposições de 2 Gy cada. Quatro implantes de titânio foram instalados nos alvéolos frescos, imediatamente após as extrações dos terceiro e quarto pré-molares, totalizando 48 implantes controles e 48 experimentais (uso de CTM-MO+PRP). Os animais foram eutanasiados 90 dias pós-implantação. Foram analisados o percentual de implantes perdidos (PIP), o contato osso-implante (COI), e a densidade óssea no interior das roscas (DOIR). Resultados: A eficiência de isolamento das CTMs-MO foi de 100% e em cultura as células apresentaram morfologia fibroblastóide. As células foram positivas para CD90 (88,6%), CD29 (89,8%), CD44 (86,9%) e negativas para CD34 (1,6%), CD45 (1,8%), CD14 (1,8%) e MHC-II (2,7%). As células foram diferenciadas em adipócitos, demonstrado pela presença de vacúolos lipídicos no interior das células; osteoblastos, pela mineralização da matriz extracelular e condrócitos pela presença de lacunas ao redor dos condrócitos jovens. A maior expressão gênica de AP2, ALP e COL II em células induzidas também confirmou o potencial de diferenciação (p < 0,001; p < 0,001; p = 0,031; respectivamente). Os PIP nos lados controle e experimental foram respectivamente 25,0% e 18,7% no grupo A (p = 0,686), 31,2% e 25,0% no grupo B (p=0,686) e 68,7% e 68,7% no grupo C (p =1,000). Na comparação entre os três grupos, o PIP apresentou diferença estatisticamente significante tanto no lado controle (p=0,041) como no experimental (p = 0,047). Os percentuais de COI nos lados controle e experimental foram respectivamente 39,0 e 27,7 no grupo A (p = 0,110); 20,9 e 16,7 no grupo B (p=0,347) e 16,0 e 7,1 no grupo C (p = 0,310), com diferença estatística entre os grupos tanto no lado controle (p = 0,033) quanto no experimental (p=0,046). As DOIR nos lados controle e experimental foram respectivamente 46,8 e 36,5 no grupo A (p = 0,247); 29,3 e 24,1 no grupo B (p = 0,379) e 21,0 e 11,6 no grupo C (p = 0,421), porém com diferença estatisticamente significante entre os três grupos somente no lado controle (p=0,025). Conclusões: As CTMs-MO de Minipigs BR-1, obtidas com o protocolo utilizado neste estudo são células-tronco, podendo ser aplicadas em ensaios pré-clínicos na medicina regenerativa. Os resultados mostraram um efeito negativo da radiação ionizante na neoformação óssea periimplantar tanto no grupo B quanto no C. Após a RT a perda de implantes foi três vezes maior que em osso não irradiado. A RT realizada 15 dias após a instalação dos implantes não interferiu na perda de implantes, sugerindo que este seria o melhor momento para reabilitação bucal com implantes dentários. Com a metodologia empregada, o uso da associação CTMs-MO+PRP previamente à instalação de implantes não apresentou efeito positivo significante na neoformação óssea periimplantar
Introduction: Patients with head and neck cancer are usually treated by a combination of surgery, radiotherapy (RT) and chemotherapy. In many cases, oral rehabilitation with implant-supported prostheses is the best option for a proper functional recover. However, in irradiated patients procedures as dental extractions and implants are risk factors for developing osteoradionecrosis. Several experimental studies have shown that the use of mesenchymal stem cells (MSCs) associated with growth factors such as platelet-rich plasma (PRP) provides improvement in bone regeneration and osseointegration, being considered an alternative to bone defects or injury. Objectives: To isolate and characterize MSCs from bone marrow (BM) of Brazilian minipigs (Minipigs BR-1), to evaluate the effect of RT and of BM-MSCs+PRP in the osseointegration of implants placed in fresh sockets, by histological and histomorphometric analysis of the bone-implant interface. Methods: BM-MSCs from 12 adult male minipigs were isolated from the iliac crest. After 21 days of culture, cell differentiation potential was assessed by staining and RT-PCR. The immunophenotypic profile was characterized by flow cytometry. The animals were divided into three groups: Group A (control group, no RT), Group B (implants placement 15 days before RT) and Group C (implants placement three months after RT). The total radiation dose for each side of the mandible was 24 Gy, divided into 3 doses of 8 Gy with a 7 dayinterval for each dose, which is biologically equivalent to approximately 56 Gy, with 28 sections of 2 Gy each. Four titanium implants were installed in the alveoli fresh, immediately after the extraction of the third and fourth premolars of each hemimandible, totalling 48 implants on the control side and 48 on the experimental side (using BM-MSCs+PRP). The animals were euthanized 90 days post-implantation. The implant loss rate (ILR), the bone-implant-contact (BIC) and bone density inside the threads (BDIT) were determined in each group. Results: The efficiency of the isolation of BM-MSCs was 100%, and in culture, the cells showed fibroblastoid morphology. Cells were positive for CD90 (88.6%), CD29 (89.8%), CD44 (86.9%) and negative for CD34 (1.6%), CD45 (1.8%), CD14 (1.8%) and MHC-II (2.7%). Cells were differentiated into adipocytes, as demonstrated by the presence of lipid vacuoles in the cells, osteoblasts, by mineralization of extracellular matrix and chondrocytes, by the presence of gaps around the young chondrocytes. The higher gene expression of AP2, ALP and COL II at induced cells also confirmed the differentiation potential (p < 0.001, p < 0.001, p=0.031; respectively). The ILR in control and experimental sides were respectively 25.0% and 18.7% in group A (p=0.686), 31.2% and 25.0% in group B (p = 0.686) and 68.7% and 68.7% in group C (p =1.000), with a statistically significant difference between the three groups at the control side (p = 0.041) and at the experimental side (p = 0.047). The percentage of BIC in control and experimental sides were respectively 39.0 and 27.7 in group A (p = 0.110), 20.9 and 16.7 in group B (p = 0.347) and 16.0 and 7.1 in group C (p = 0.310), with statistical significance between the groups at the control side (p = 0.033) and at the experimental side (p = 0.046). The BDIT in experimental and control sides were respectively 46.8 and 36.5 in group A (p = 0.247), 29.3 and 24.1 in group B (p = 0.379) and 21.0 and 11.6 in group C (p = 0.421), with statistical significance between the three groups only at the control side (p = 0.025). Conclusions: The BM-MSCs of Minipigs BR-1 obtained with this protocol can be used in pre-clinical regenerative medicine since they are stem cells. The results showed a negative effect of RT in peri-implant bone regeneration in group B and C. The implant loss was three times higher in irradiated bone than in non-irradiated one. The RT performed 15 days after implant placement did not interfere with implant loss, suggesting that this would be the best time for oral rehabilitation with dental implants. With this methodology, the use of BM-MSCs+PRP before the implant placement did not show any significant positive effect on peri-implant bone regeneration

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Konan, S. "Augmenting osseointegration of implants using bone marrow stromal cells." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1382600/.

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Introduction: The greatest challenge facing the success of orthopaedic implants is improving their fixation to bone to enhance their longevity. Bone marrow stromal cells (BMSC), are a population of plastic-adherent cells derived from the bone marrow. The main hypothesis of this thesis is that viable BMSC can be applied to implants using a fibrin glue-spray system; and increase bone formation adjacent to the implants and improve bone-implant contact. Methods: The experiments were undertaken in a large animal model. Four scenarios were tested 1) The ability of BMSC to improve implant fixation using models of total hip replacement, massive endoprosthetic replacement and bone defect around pins. 2) The effect of varying cell dosages of BMSC in their ability to produce new bone and improve bone implant contact. 3) The effect of differentiating the BMSC along the osteogenic pathway in their ability to produce new bone and improve bone implant contact. 4) The effect of using semi-permeable barriers around BMSC sprayed on implants to prevent cell migration Results: 1) BMSC sprayed on the surface of implants resulted in increased bone formation in the total hip replacement, massive endoprosthetic replacement and bone defect around pin models. 2) Bone formation was higher with osteogenic 10x106 BMSC (112.67 ± 30.75 mm2) compared to osteogenic 2x106 BMSC (76.84 ± 2.25 mm2). No significant difference was noted in bone formation between undifferentiated 1x105 BMSC (30.76 ± 9.43%) and undifferentiated 10x106 BMSC (28.27 ± 14.64%). 3) Osteogenic differentiated 10x106 BMSC (112.67 ± 30.75 mm2) produced more bone than undifferentiated 10x106 BMSC (58.22 ± 17.22 mm2). 4) Using semipermeable barriers resulted in significantly increased bone formation when undifferentiated 1x105 BMSC (61.32 ± 6.94% vs 30.76 ± 9.43%) or undifferentiated 10x106 BMSC (57.46 ± 4.39% vs 28.27 ± 14.64%) was used. This difference was not noted when osteogenic differentiated 10x106 BMSC was used. The experiments confirm that viable BMSC can be successfully isolated from bone marrow aspiration, differentiated along the osteogenic pathway and sprayed on the surface of various orthopaedic implants to improve bone-implant contact. Conclusion: This technique of using BMSC may be an ideal alternative to improve osseointegration of implants in challenging clinical scenarios with deficient bone stock.

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da, Silva Barros Sara Maria. "Development of hybrid coatings for osseointegration improvement of metal dental implants." Doctoral thesis, Universitat Jaume I, 2016. http://hdl.handle.net/10803/398841.

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Los implantes de titanio presentan comprobada biocompatibilidad no obstante carecen de propiedades osteoinductoras. Las estrategias actuales de modificación superficial de los implantes no resultan plenamente efectivas en casos particulares de baja calidad del hueso receptor. La presente tesis doctoral plantea una nueva estrategia basada en recubrimientos superficiales bioabsorbibles de base silicio para mejorar el éxito de dichos implantes. Para alcanzar dicho objetivo se han sintetizado vía sol-gel diversos recubrimientos a partir de los precursores de silicio trimetoximetilsilano (MTMOS), 3-glicidoxipropiltrimetoxisilano (GPTMS) y tetraetoxisilano (TEOS). Se ha realizado una detallada caracterización de los recubrimientos, especialmente en lo que a sus propiedades físicas, químicas y biológicas se refiere. Los resultados obtenidos muestran que todos los recubrimientos se encuentran bien adheridos a la superfície metálica, además, el prototipo final ha demostrado ser claramente biocompatible con los tejidos vivos sin mermar las propiedades osteoconductivas de los implantes de titanio comerciales.
Titanium dental implants have proved biocompatibility, nevertheless, they lack of osteoinductive properties. The usual strategy of modifying titanium dental implants' surfaces is not fully effective in the special situations of poor bone quality. THis work focuses on a new strategy that consists on developing synthetic and biologically absorbable silica-based external coatings to improve these implants' success. In order to achieve this purpose, sol-gel technology was used to synthesize several coatings based on the precursors trimethoxymethylsilane (MTMOS), 3-glycidyloxypropylsilane (GPTMS) and tetraethoxysilane (TEOS). The coatings were thoroughly characterized, specifically focusing on their physical and chemical properties as well as on their biological performance. Resukts show taht all the synthesized coatings were well adhered to the metal surface and the final prototype shows clear biocompatibility with living tissues without affecting the osteoconductive properties of the commercial titanium dental implants.

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Carvalho, Marcelo Diniz. "Avaliação histometrica do efeito da fumaça de cigarro sobre o reparo e qualidade ossea ao redor de implantes de titanio em ratas com deficiencia induzida de estrogeno." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290844.

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Orientadores: Enilson Antonio Sallum, Francisco Humberto Nociti Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-04T03:11:36Z (GMT). No. of bitstreams: 1 Carvalho_MarceloDiniz_M.pdf: 838460 bytes, checksum: d0aff5d2298e732ab336cd58428d002a (MD5) Previous issue date: 2005
Resumo: O objetivo do presente estudo foi avaliar a influência da fumaça de cigarro na presença da deficiência de estrógeno sobre o reparo ósseo ao redor de implantes de titânio. Foram utilizadas 45 ratas (Wistar) divididas em 3 grupos: ovariectomia simulada (SHAM, n=15), ovariectomia (OVX, n=15) e exposição a fumaça de cigarro (EFM) associada a OVX (EFM+OVX, n=15). No grupo EFM+OVX, a EFM iniciou-se 60 dias antes da colocação dos implantes e manteve-se até o fim do período experimental. Todos animais receberam um implante em uma das tíbias e no mesmo período cirúrgico foram realizadas as OVX e SHAM. Sessenta dias após as cirurgias, os animais foram mortos e secções não descalcificadas obtidas para avaliação dos seguintes parâmetros: porcentagem de osso na região adjacente ao implante (500 µm) (OA), porcentagem de preenchimento ósseo dentro dos limites das roscas de cada implante (PR) e porcentagem de contato ósseo direto com a superfície do implante (CD). As medidas foram obtidas separadamente para região A (cortical) e B (medular). Os resultados deste estudo mostraram que, na região A, o grupo EFM+OVX apresentou uma menor OA e um menor CD quando comparado aos outros grupos (p<0,05). Na região B, menores valores de CD e OA foram observados no grupo EFM+OVX, seguidos dos grupos OVX e SHAM, respectivamente (p<0,05). Já para PR, os grupos EFM+OVX e OVX se comportaram de maneira semelhante diferindo do grupo SHAM (p<0,05). Conclui-se que, dentro dos limites deste estudo, a exposição à fumaça de cigarro amplificou os efeitos da deficiência de estrógeno, prejudicando a qualidade e o reparo ósseo ao redor de implantes de titânio inseridos em tíbias de ratas ovariectomizadas
Abstract: Background: Smoking has been considered one of the main risk factors for osteoporosis. Cigarette smoke inhalation and estrogen deficiency have been proving to negatively affect bone healing around titanium implants. Thus, the purpose of this study was to investigate the effect of cigarette smoking inhalation on bone around titanium implants in estrogen deficiency rats. Methods: Fourth-five female wistar rats had the tibia surface exposed for the placement of a screw-shaped titanium implant (4.0mm in length; 2.2mm in diameter). The animals were randomly assigned to group SHAM (sham operated rats / n=15), group OVX (ovarectomized rats / n=15) and group CSI+OVX (2 months of intermittent cigarette smoke inhalation (CSI) prior and 2 months after implant placement in ovariectomized rats/ n=15). The implants were placed at the same time of OVX or Sham surgery. After 60 days the animals were sacrificed and undecalcified sections obtained. Percentage of bone in a 500mm-wide zone lateral to the implant (BO), bone filling within the limits of the threads (BF) and bone-to-implant contact (BC) was measured in cortical (zone A) and cancellous (zone B) bone separately. Results: Data analysis showed that, in zone A, a decreased BO and BC was observed for CSI+OVX (p <0.05). In zone B, the CSI+OVX group showed the lowest values for BO and BC, followed by groups OVX and SHAM, respectively (p<0.05). Similar values of BF were observed for CSI+OVX and OVX groups, that were lower than the ones obtained by SHAM group (p <0.05). Conclusion: Within the limits of the present investigation, cigarette smoke inhalation amplified the effects of estrogen deficiency on bone around titanium implants inserted in ovariectomized rats
Mestrado
Periodontia
Mestre em Clínica Odontológica

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Garcia, Ricardo Vieira [UNESP]. "Utilização de plasma rico em plaquetas (PRP) associado a implantes intra-ósseos em mandíbulas de cães: análise histológica." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/104737.

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Made available in DSpace on 2014-06-11T19:33:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02-23Bitstream added on 2014-06-13T19:04:24Z : No. of bitstreams: 1 garcia_rv_dr_arafo.pdf: 835717 bytes, checksum: a0b9b5864c4b43379791c577605859ae (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo deste estudo foi investigar através de análise histológica a influência do plasma rico em plaquetas (PRP) na neoformação óssea dos espaços peri-implantares de implantes osseointegráveis instalados em mandíbula de cães. Foram utilizados 9 cães sem raça definida. Inicialmente foram realizados exodontias dos segundos e terceiros pré-molares, bilateralmente. Após 60 dias, as áreas foram preparadas para instalação de implantes osseointegráveis, sendo que os implantes instalados do lado direito da mandíbula não receberam tratamento com PRP, servindo como controle. Para o lado esquerdo, os implantes foram instalados em associação ao PRP, caracterizando o grupo experimental. Biópsias ósseas foram obtidas nos períodos de 15, 30, 55 dias após instalação dos implantes. Pelos resultados histológicos, de modo geral, pode-se concluir que o tratamento com PRP, conforme a metodologia empregada, não favoreceu a neoformação óssea e em alguns espécimes promoveu a formação de tecido fibroso.
This study was designed to evaluate, by means of histological analysis, the effect of platelet-rich plasma (PRP) on bone formation in the interface with osseointegrated implants placed in the dog mandible. Nine dogs of mixed race were used. Initially, the second and third inferior premolars were extracted bilaterally. After 60 days, osseointegrated implants were placed. On the right side of the mandible no treatment was done and those implants served as controls. On the left side, the implants were placed in association with PRP. Bone biopsies were taken after 15, 30 and 55 days. Results showed that PRP did not enhance bone formation and favored fibrosis in some specimens.

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