Orientadores: Marcus Alexandre Finzi Corat, Anderson de Oliveira Lobo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T10:38:02Z (GMT). No. of bitstreams: 1 Paula_MirianMichelleMachadode_M.pdf: 2407271 bytes, checksum: 8f5ae942d781fb23b3d817baa3c8a868 (MD5) Previous issue date: 2014 / Resumo: As promessas da utilização de nanotubos de carbono (CNTs) para fins biomédicos se esbarram em algumas dificuldades. Muitos estudos de nanotoxicologia foram realizados analisando propriedades destes materiais em causar injúrias no tecido vivo. Apesar das evidências da citotoxicidade dos CNTs, existe também um grande número de publicações de estudos de biomateriais baseados em CNTs que suportam sua biocompatibilidade. Segundo Lobo et al, 2009 (1), os nanotubos de carbono de parede múltipla (MWCNT) foram suficientes para obter biocompatibilidade. As estruturas de VAMWCNT alinhados revelaram que um ínfimo contato entre as estruturas das células e a nanotopografia é decisivo para garantir a bioatividade e eficiência no crescimento e espalhamento celular sem produzir efeitos citotóxicos. Resultados do nosso grupo mostrou características da adesão celular em substrato contendo VAMWCNT alinhado através da análise de proteínas envolvidas no mecanismo de adesão, assim como, estudo comparativo de preferência de substrato para proliferação e viabilidade celular onde verificou-se um melhoramento de adesão e espalhamento celular de acordo com o substrato de VAMWCNT utilizado, com ou sem tratamento de funcionalização a plasma de oxigênio. No entanto os substratos de VAMWCNT, apesar de atóxico, parecem provocar mudanças no comportamento celular principalmente no primeiro contato e durante o processo de adesão das células ao substrato. Neste estudo verificou-se que os substratos com VAMWCNT-O promoveram respostas pró-inflamatórias comparado ao controle. Os substratos com tratamento a plasma de oxigênio mostraram promover um maior estimulo celular dos macrófagos quanto a expressão de interleucina 6 além disso, verificou uma correlação entre os substratos hidrofílicos em maior produção de citocinas com o aumento de migração celular de células mononucleares da medula óssea in vivo. Mostrando, assim, que estes substratos podem acarretar uma melhora na estimulação do recrutamento celular e que podem favorecer o processo regenerativo de um tecido lesionado. Estes resultados demonstram um potencial do uso deste biomaterial na medicina regenerativa no futuro / Abstract: The promise of the use of carbon nanotubes (CNTs) for biomedical purposes faces some difficulties. Many studies of nanotechnology has been realized by analyzing the properties of these materials causing tissue injury in vivo. Despite evidence of cytotoxicity of CNTs, there are also a large number of published studies of biomaterials based on CNTs that support the idea of their biocompatibility. According to Lobo et al, 2009 (1), carbon nanotube multi-wall (MWCNT) showed biocompatibility. Vertically aligned VAMWCNT revealed that the contact between the structures of the cells and nanotopography is crucial to ensure bioactivity, cell growing and cell spreading, avoiding cytotoxic effects. Results from our group have showed cell adhesion on substrate containing VAMWCNT, as well as, variability of cell adhesion and spreading according to wet-ability features after oxygen plasma treatment (VAMWCNT-O) and density of the VAMWCNT substrate. However, VAMWCNT-O substrates, although nontoxic, seem to cause changes in cell behavior in the first contact and during the process of cell adhesion to the substrate. To better understand the behavior of cells on the substrates of VAMWCNT-O, in the present study, we analyzed the properties of macrophages to trigger inflammatory response in contact with substrates containing CNTs correlating it with mononuclear bone marrow cells migration. It was found that substrates with carbon nanotubes promoted pro-inflammatory responses compared to the control. The substrates after oxygen plasma treatment showed higher stimulation of macrophages as expression of interleukin 6 and SDF-1. They showed direct correlation with increasing bone marrow cell migration in vitro and in vivo. These substrates leaded to an improvement to cell recruitment and stimulation, which might support the process of regenerating an injured tissue by using them in regenerative medicine / Mestrado / Clinica Medica / Mestra em Clínica Médica

Orientadores: Paulo Kharmandayan, Ivan Felizardo Contrera Toro / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T14:18:09Z (GMT). No. of bitstreams: 1 Calderoni_DaviReis_D.pdf: 2411163 bytes, checksum: f124b9aeaf19c6f4e86c382fef12ffeb (MD5) Previous issue date: 2014 / Resumo: Introdução: A reparação de um defeito craniano é um procedimento desafiador, que requer não somente o preenchimento da falha óssea mas também estabilidade a longo prazo do material empregado e restabelecimento do contorno e simetria. Diversos tipos de materiais com diferentes características bem como diferentes métodos de produção dos implantes vêm sendo testados, sem que ainda haja um substituto ósseo considerado ideal. No presente estudo foram investigadas as propriedades de osteointegração de implantes da liga Ti6Al4V construídos por prototipagem com poros tridimensionalmente conectados considerando a influência do recobrimento dos mesmos com uma camada delgada de ?-fosfato tricálcico nestas propriedades. Método: Trinta ratos foram submetidos à criação de defeitos ósseos bilaterais na calvária, que foram preenchidos com implantes, recobertos ou não com ?-fosfato tricálcico, de modo aleatório. Os animais foram distribuídos em grupos e sacrificados 15, 45 e 90 dias após o procedimento. A integração dos implantes foi inicialmente avaliada por ensaio de compressão. A interface osso-implante foi analisada por meio de microscopia eletrônica de varredura. Resultados: A força máxima para produzir o deslocamento inicial dos implantes foi aumentando durante o período estudado, alcançando valores da ordem de 100N para ambos os tipos de implante. Foi observada integração entre o osso e a superfície dos implantes, com crescimento ósseo progressivo no interior dos poros. Não foram observadas diferenças significativas entre implantes recobertos e não recobertos por ?-fosfato tricálcico. Conclusão: Foi alcançada uma adequada osteointegração nas reconstruções cranianas utilizando implantes prototipados da liga Ti6Al4V com as características de porosidade e superfície descritas, sem influência do recobrimento cerâmico adotado. Os resultados sugerem que as características de construção utilizadas podem ser incorporadas aos implantes para reconstrução craniana para melhorar os resultados cirúrgicos / Abstract: Background: The repair of a calvarial defect is a challenging procedure, requiring not only filling of the bone gap but long term stability of the employed material and satisfactory contour and symmetry. Several types of materials with different characteristics have been studied, as well as various methods of implant production. However, to date no ideal bone substitute has been found. The osseointegration properties of porous prototyped implants with tridimensionally interconnected pores made of the Ti6Al4V alloy and the influence of a thin layer of calcium phosphate coating were investigated. Methods: Bilateral critical size calvarial defects were produced in thirty rats and filled with coated and uncoated implants in a randomized fashion. The animals were distributed in groups and kept for 15, 45 and 90 days before sacrifice. Implant mechanical integration to bone was evaluated with a push-out test. Bone-implant interface was analyzed using scanning electron microscopy. Results: The maximum force to produce initial displacement of the implants increased during the study period, reaching values around 100N for both types of implants. Intimate contact between bone and implant surface was present, with progressive bone growth into the pores. No significant differences were seen between coated and uncoated implants. Conclusion: Adequate osseointegration can be achieved in calvarial reconstructions using prototyped Ti6Al4V scaffolds with the described physical characteristics of surface and porosity. The results suggest that the proposed implant design characteristics can be incorporated into calvarial implants to improve reconstructive results. / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências

Orientador: Marcelo Ferraz Mesquita / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-27T20:29:16Z (GMT). No. of bitstreams: 1 Rodrigues_SabrinaAlessandra_D.pdf: 2058256 bytes, checksum: 25d619422634beb160a254baa71e150a (MD5) Previous issue date: 2015 / Resumo: O objetivo neste estudo foi avaliar o comportamento de estruturas fundidas em titânio, soldadas à LASER (Light Amplification by Stimulated Emission of Radiation) e à TIG (Tungsten Inert Gas), em relação ao desajuste marginal (bi e tridimensional), força de destorque dos parafusos protéticos, fadiga mecânica, corrosão e tensão induzida aos análogos de mini pilares protéticos. Cinquenta estruturas foram fundidas em titânio comercialmente puro (Ti-cp); vinte infraestruturas (n=20) simulando próteses fixas múltiplas de três elementos; e trinta halteres (n=30). Para cada infraestrutura foram confeccionados dois tipos de index, simulando um desajuste marginal de 200 µm. Um index em gesso especial, para desenvolvimento da análise de tensão, e outro em resina fotoelástica, para avaliação do desajuste marginal (bi e tridimensional), força de destorque, fadiga mecânica e corrosão. Antes e após os procedimentos de soldagem (LASER ou TIG) foram realizadas as seguintes avaliações: mensuração do desajuste marginal, por meio de microscópio óptico (bidimensional) e microtomógrafo de raio-X (tridimensional); análise da tensão induzida aos mini pilares protéticos, por meio da técnica extensométrica; e mensuração da força de destorque dos parafusos protéticos. Os procedimentos de soldagem foram relizados com os seguintes parâmentros: LASER (370/9ms); TIG (36A/60ms). Após a realização dos procedimentos de soldagem (LASER ou TIG) as infraestruturas foram submetidas à ciclagem mecânica ( 280 N/ 106 ciclos /2Hz) para avaliação da força de destorque dos parafusos protéticos pós-ciclagem. A longevidade das estruturas intactas e soldadas (LASER ou TIG) também foi avaliada, por meio de ensaios mecânicos de fadiga, e o comportamento à corrosão, por meio de testes eletroquímicos de espectroscopia de impedância eletroquímica e polarização potenciodinâmica. Os resultados foram analisados estatisticamente (ANOVA fator único/ Teste de Tukey HSD/Teste t de Student/ (?=0,05)). Ambos os procedimentos de soldagem diminuíram o nível de desajuste marginal (bi e tridimensionalmente), aumentaram a intensidade da força de destorque e reduziram a tensão induzida aos mini pilares protéticos. Contudo, após a ciclagem mecânica houve diminuição da intensidade da força de destorque dos parafusos protéicos. As estruturas soldadas à LASER tiveram maior resistência a fadiga, comparada as estruturas soldadas à TIG. O teste de espectroscopia de impedância foi significativo para as infraestruturas soldadas à TIG, comparado com as infraestruturas intactas e soldadas à LASER. Conclui-se que os procedimentos de soldagem tiveram influência sobre a adaptação marginal das infraestruturas, proporcionando maior estabilidade ao sistema implantossuportado. A ciclagem mecânica teve influência sobre a estabilidade dos parafusos protéticos, sendo necessárias proservações periódicas durante o uso da prótese para reaperto e/ou troca dos parafusos. Estruturas fundidas em titânio e soldadas à LASER possuem maior resistência à fadiga do que estruturas soldadas à TIG. Eletroquimicamente, o procedimento de soldagem à LASER possuem melhor comportamento à corrosão comparado ao procedimento de soldagem à TIG / Abstract: The aim of this study was to evaluate titanium casted structures behavior, welded by LASER (Light Amplification by Stimulated Emission of Radiation) and TIG (Tungsten Inert Gas), on marginal misfit (two and three-dimensional), prosthetic screws detorque strength, mechanical fatigue, corrosion and stress induced to the prosthetic mini abutment analogs. Fifty structures were casted in commercially pure titanium (cp-Ti); twenty frameworks (n=20) simulating multiple prostheses of three elements; and thirty dumbbells (n=30). From the frameworks were fabricated two type of index, simulating a marginal misfit of 200µm. One index was fabricated in special plaster to the development of stress analysis, and other in epoxy resin to the development of marginal misfit analysis (two and three-dimensional), detorque strength, mechanical fatigue and corrosion. Before and after welding procedures (LASER or TIG) were developed the following evaluation: marginal misfit analysis, by optical microscope (two-dimensional) and X-ray microtomography (three-dimensional); induced stress analysis on prosthetic mini abutment analogs, by extensometric technique; and measurement of prosthetic screws detorque strength. The welding procedures were made with the following parameters: LASER (370V/9ms); TIG (36A/60ms). After welding procedures (LASER or TIG), the frameworks were submitted to cyclic mechanical (280N; 106 cycles; 2 Hz) by oblique compressive load to evaluation of the detorque strength after the cycling. The longevity of the welded structures was also evaluated by mechanical fatigue testing, and the corrosion behavior by electrochemical tests of electrochemical impedance spectroscopy and potentiodynamic polarization. The results were analyzed statistically (one-way ANOVA / Tukey HSD test / Student-t test (? = 0.05)). Both the welding procedures decreased the marginal misfit level (two and three-dimensionally), increased the detorque strength and decreased of stress induced on prosthetic mini abutment analogs. However, after the mechanical cycling there was decrease of detorque strength of prosthetic screws. The structures welded by LASER had high fatigue resistance than the structures welded by TIG. The impedance spectroscopy test was only significant for frameworks welded by TIG, compared with intact and LASER welded LASER frameworks. It is concluded that welding procedures had influence on marginal fit, providing more stability to the implant-supported system. The mechanical cycling had influence on prosthetic screws stability, being necessary periodic following up to tighten and/or exchange of prosthetic screws. The titanium casted and LASER welded structures were more fatigue resistance than that TIG welded structures. Electroless, LASER welding procedure have better corrosion behavior compared to TIG welding procedure / Doutorado / Protese Dental / Doutora em Clínica Odontológica

No description available.

No description available.

OBJECTIVES: The purpose of this in vitro study is to measure and compare the accuracy of the conventional impression, the intraoral scanner, and the photogrammetry techniques for full-arch implant-supported dental prostheses at the abutment level. METHODS: An edentulous maxillary master model containing 6 implant abutment replicas (RP analog for screw-retained abutment straight from NobelReplace® Multi-unit Abutment Plus Replica) was fabricated. A reference STL of the master model was obtained using a desktop scanner (inEos X5, Dentsply Sirona) with high trueness and precision and served as the control STL. Three impression techniques were performed: the intraoral scanning (IOS) group (TRIOS 3 Battery Cart, 3Shape A/S), the photogrammetry (PTG) group (ICam 4D Generation 3, Imetric), and the conventional (CNV) group. Ten impressions from each group were tested. Scan bodies in each STL file acquired from the different impression techniques were converted to implant abutment replicas using a digital library. Three tests were completed to compare the different registration techniques. A 3D deviation test between the experimental group and the reference was done on an inspection software (IScan4D Dental Version 9.1.104; Imetric) using a “best fit” algorithm to obtain the root mean square values, and on another inspection software (IScan3D Dental Version 9.1.104; Imetric) using spatial similarity transformation. The second test was meant to assess the angular deviations of the implant abutment replicas using a reverse engineering software (Geomagic Control X 2020.1; 3D Systems). The final test for cross-arch distances was done on an inspection software (IScan3D Dental Version 9.1.104; Imetric) which allows to determine the 3-dimensional coordinates for each implant by using the origin point and compare the cross-arch distance deviations as well as deviations at the x-, y-, and z- coordination. Trueness and precision were the two parameters used to define the accuracy of a system. The term "trueness" was used to see how close the measurements from the experimental files of each group were to those of the reference file. The term "precision" was defined as to see how close the measurements of each experimental files were to each other within the same group. The 3D discrepancies were then calculated and the trueness and precision of the three impression techniques were assessed and compared statistically (α = 0.05). RESULTS: The root mean square of 3D deviation values through the ICP “best-fit” method showed statistically significant differences between the PTG and CNV group (p < .0001), and the PTG and IOS group (p < .0001). The CNV and IOS group did not show statistically significant differences (p = 0.8626) through the “best-fit” method, but significant differences were observed via the “spatial similarity” method (p = 0.0041). Both methods however showed the best results in terms of trueness for the PTG group, followed by the CNV group and least the IOS group. In terms of precision, PTG showed the best results, followed by the IOS group and least the CNV group. The angular deviation test using the “best-fit” alignment method showed that the PTG and CNV had no statistically significant difference (p = 0.7955) and were equivalent. However, both showed a statistically significant difference to the IOS group (p < .0001), which had the highest angular deviation. Finally, in terms of cross-arch distances, the photogrammetry group showed optimal results followed by the IOS group and then the CNV group. In general, the shorter the inter-arch distance, the lower the deviation was. A larger deviation was observed on longer inter-arch distances. Considering the deviations on the 3 axes of each implant, the CNV technique had the highest deviation in the X-axis (longitudinal) and the IOS technique showed the highest deviation on the Y-axis (lateral) and Z-axis (vertical). The PTG technique experienced significantly less deviation on the X-axis, Y-axis, and the Z-axis. CONCLUSION: Within the scope of this study, the photogrammetry technique reported the best accuracy in terms of trueness and precision of implant positions for complete-arch implant rehabilitation. Conventional impressions showed better accuracy results than intraoral scanning in the 3D deviations test and global angular deviation test, however the latter exhibited better results in terms of accuracy in terms of cross-arch distances test. / 2023-08-11T00:00:00Z

Esophageal and biliary stents are indwelling devices used in the treatment of selected gastrointestinal and biliary disorders. Stenting is accepted as a standard procedure for palliation of malignant obstruction of the esophagus and biliary system. Review of the early and late complications associated with these devices is made with emphasis on the clinical and radiographic features. A suggested approach to diagnosis and treatment recommendations are made for each complication that the emergency department physician may encounter.

No description available.

No description available.

Mål: Målet med den retrospektiva studien var att bedöma den kliniska kvaliteten av metallkeramiska broar i titan-porslin (Ti) och kobolt-krom-porslin (Co-Cr) med en minsta uppföljningstid på två år.Material och metod: 49 patienter behandlades med metallkeramiska broar i Ti och Co-Cr på avdelningen för Oral Protetik på Odontologiska fakulteten i Malmö under perioden 2007-2010. År 2012 kontaktades dessa patienter efter att tandteknikerfakturor gåtts igenom. 21 patienter (10 män och 11 kvinnor), med en medelålder på 59,2 år och 25 broar (13 Ti och 12 Co-Cr), deltog i studien. Broarnas kliniska kvalitet bedömdes med hjälp av en modifierad version av California Dental Association (CDA) kvalitetbedömningssystem. En bedömning av lyckande- och överlevnadsfrekvens genomfördes. Statistisk analys gjordes med hjälp av Fishers’ exact test vid bedömning av skillnaden mellan grupperna. För bedömning av skillnaden mellan bedömarna beräknades kappa värdet.Resultat: Det förelåg ingen statistiskt signifikant skillnad mellan grupperna vad gäller bedömningen med CDA kvalitetbedömningssystem. Sju broar i Ti-gruppen, och åtta i Co-Cr-gruppen bedömdes som ”acceptable”. Sex Ti-broar och tre Co-Cr-broar bedömdes vara i behov av revision (”correct/replace”). Överlevnadsfrekvensen var 81,3 % för Ti-broarna och 92,3 % för Co-Cr-broarna. Tre Ti-broar och två Co-Cr-broar hade frakturer i fasadporslinet – s.k. "chip-off”-frakturer. Inom vardera grupp fanns en bro med karies på stödtänderna.Slutsatser: Broarna visade acceptabel kvalitet inom båda grupperna. Med tanke på begränsningarna för den här studien bör försiktighet vidtas när man drar slutsatser utifrån resultaten. / Aim: The aim of this retrospective study was to evaluate the clinical quality of titanium (Ti) metal-ceramic and cobalt-chromium (Co-Cr) metal-ceramic fixed dental prostheses(FDPs) with a minimum follow up period of 2 years.Methods: In 2012, 49 patients treated with FDPs during 2007-2010 at the Department of Prosthetic Dentistry, Faculty of Odontology, Malmö University, Sweden, were contacted after auditing dental technician bills. Twenty-one patients with a mean age of 59.2 years with 25 FDPs (13 Ti and 12 Co-Cr FDPs) agreed to participate in the study (10 men and 11 women). Evaluation of the metal-ceramic FDPs was made using a modified version of the California Dental Association (CDA) evaluation system. Success and survival rates were assessed. Statistical analysis was performed using Fisher’s exact test for differences between groups and for inter-examiner reliability the kappa value was calculated.Results: The two groups did not differ significantly concerning the ratings according to the CDA evaluation system. Seven FDPs in the Ti group were evaluated as acceptable while there were 8 in the Co-Cr group. Six Ti and 3 Co-Cr FDPs were evaluated as correct/replace. The survival rate for the Ti FDPs was 81.3% and for the Co-Cr FDPs 92.3%. Three Ti FDPs showed chip-off fractures while two were recorded in the Co-Cr group. In either group one FDP exhibited caries on the abutment teeth.Conclusions: Within the limitations of this study the clinical quality of the fixed dental prostheses was acceptable in both groups.