Processo E Equipamento De Cura Localizada De Resina Termosensìvel E Estereolitografia Com Laser Na Região Espectral Do Infravermelho Para Construção De Protótipos

Nova técnica de prototipagem rápida denominada esterolitografia destinada ao estudo e confecção de peças tridimensionais com geometrias desejadas, feitas através da interação do laser de CO2, com comprimento de onda de 10,41m, com resinas termosensíveis de alta viscosidade, como resina epóxi. Esta técnica combina a computação gráfica, com um software especialmente desenvolvido, a ciência dos polímeros e a tecnologia do laser operando na região espectral do infravermelho. Onde o processo é composto pelas seguintes etapas principais: (a) preparação da resina termosensível ; (b) definição do modelo a ser executado através de um software próprio ou qualquer software disponível no mercado (CAD), em finas seções transversais ou por fatiamento do sólido ou peça; (c) determinação da trajetória do Laser através de microvetores de acordo com o desenho fatiado da peça; (d) efetivação da varredura do Laser pela superfície da resina, com velocidade variável, de acordo com o programa e as especificações já definidas; (e) efetivação da cura localizada nas áreas iluminadas pelo Laser, efetivando a solidificação da camada de finida pelo fatiamento, cada vez que este cobre ou desenha uma nova seção da peça; (f) repetição do processo para cada camada da peça definida pelo software até a obtenção da peça final. E onde o equipamento trata-se de um sistema estereolitográfico consistindo basicamente de um módulo de controle de varredura laser opto-eletrônico (1), um laser de CO 2 (2), um dispositivo desenvolvido para dispersão da resina de alta viscosidade (3), uma plataforma elevadora (4) e um software próprio de apoio (5).BR0207464 (A)B23K26/38B23K26/38BR20020207464B23K26/38B23K26/3

Viability assays of PLLA fibrous membranes produced by rotary jet spinning for application in tissue engineering

Tissue engineering suggests different forms to reconstruct tissues and organs. One of the ways is through the use of polymeric biomaterials such as poly(L-lactic acid) (PLLA). PLLA is a recognized material in tissue engineering due to its characteristics as biocompatibility and bioresorbability. In this work PLLA fibrous membranes were produced by a simple technique known as rotary jet spinning. The rotary jet spinning consists of fibrous membranes production, with fibers of scale nano/micrometric, from a polymeric solution through the centrifugal force generated by the equipment. The membranes formed were subjected to preliminary in vitro assays to verify the cytotoxicity of the membranes made in contact with the cells. Direct cytotoxicity assays were performed through the MTT, AlamarBlue® and Live/Dead® tests, with fibroblastic and osteoblastic cells. The results obtained in this study showed that PLLA membranes produced by rotary jet spinning showed promising results in the 24-hours contact period of the cells with the PLLA fibrous membranes. The information presented in this preliminary study provides criteria to be taken in the future procedures that will be performed with the biomaterial produced, aiming at its improvement62COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informação2008/57680-

Custom-made temporomandibular joint prosthesis: computer aided modeling and finite elements analysis

Temporomandibular Joint (TMJ) is a bilateral joint that works to perform the main activities of speaking and chewing. Because of this cyclic loading, TMJ disorders are common and greatly affect the quality of life. For this reason, it becomes necessary to replace the non-functioning joint with a prosthetic device. Since the 1930s, different TMJ implants have been developed to restore the correct functioning of TMJ and improve patient quality of life. TMJ prosthesis is a two-component replacement device composed of a condyle, placed t mandible extremities, and a glenoid fossa, localized in temporal bone and these are fixed to healthy bone by screw. In recent years, thanks to technological advancement, TMJ replacement devices can be developed starting from specific tomographic data of each patient, calling them as custom-made prosthesis. The customization process is a computational process of Computer Aided Modeling (CAM) and Computer Aided Design (CAD). It starts from tomographic data to create a tridimensional model of patient mandible and skull, then, based on computational model, TMJ prosthesis is designed and finally it is fabricated by additive manufacture. Follow-up data available in literature show that the main unresolved problem of TMJ prostheses is a kinematics that is still different from the natural one, resulting in hypomobility of implanted condyle compared to the natural one. In this panorama, this study aims to show TMJ CAM customization process and to evaluate mechanical and kinematic response of a unilateral TMJ custom-made prosthesis through Finite Elements Analysis (FEA) with Ansys software. Bilateral bite to incisors and unilateral bite to molar are simulated and mechanical stress and strain generated are evaluated7414891494CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP573661/2008-12008/57860-

Microstructural and mechanical characterization of a custom-built implant manufactured in titanium alloy by direct metal laser sintering

Custom-built implants manufacture has always presented difficulties which result in high cost and complex fabrication, mainly due to patients' anatomical differences. The solution has been to produce prostheses with different sizes and use the one that best suits each patient. Additive manufacturing technology, incorporated into the medical field in the late 80's, has made it possible to obtain solid biomodels facilitating surgical procedures and reducing risks. Furthermore, this technology has been used to produce implants especially designed for a particular patient, with sizes, shapes, and mechanical properties optimized, for different areas of medicine such as craniomaxillofacial surgery. In this work, the microstructural and mechanical properties of Ti6Al4V samples produced by direct metal laser sintering (DMLS) are studied. The microstructural and mechanical characterizations have been made by optical and scanning electron microscopy, X-ray diffraction, and microhardness and tensile tests. Samples produced by DMLS have a microstructure constituted by hexagonal alpha ' martensite with acicular morphology. An average microhardness of 370 HV was obtained and the tensile tests showed ultimate strength of 1172 MPa, yield strength of 957 MPa, and elongation at rupture of 11%CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP573661/2008-12008/57860-3; 2010/05321-

Processo De Craqueamento E Petróleo Com Laser De Co2

PROCESSO DE CRAQUEAMENTO DE PETRÓLEO COM LASER DE CO2. Um processo para o craqueamento rápido de petróleos pesados e resíduos ultra pesados de petróleo foi proposto com a finalidade de romper as cadeias de hidrocarbonetos pelo aquecimento (craqueamento) através da energia térmica gerada pela interação laser de CO2/petróleo. O processo é operado sob uma ampla variedade de condições de irradiação em uma faixa de temperatura entre 200 a 1000°C, suficiente para dar inicio as reações de craqueamento térmico.BRPI0900271 (E2); BRPI0900271 (A2)C10G15/10BR2009PI00271C10G15/1

Influence of unit cell and geometry size on scaffolds electrochemical response

Additive manufacturing is a recent tool in medicine able to fabricate scaffolds to replace or regenerate bone tissues. The process permits the user to control scaffolds parameters such as size, unit cell, porosity, wall thickness, etc. However, the use of these three-dimensional geometries might negatively affect their corrosion behaviour. This paper studies the influence of Ti-6Al-4V ELI scaffold unit cell and, geometry size on the electrochemical response. Three different types of scaffold unit cell and three different geometry sizes were fabricated by additive manufacturing technique. The porosity of the scaffolds was studied by X-ray microtomography while surface changes, by scanning electron microscopy. Electrochemical behaviour was evaluated by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in a phosphate buffered saline solution at 37 degrees C. Potentiodynamic polarization curves show that scaffolds showed a higher pitting susceptibility than solid samples at potentials higher than 1 V. EIS spectra show that the scaffolds geometry size promotes narrowing of the maximum phase angle at the high frequency range (10(2)-10(5)) due to a non-homogeneous distribution of current and potential853CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ141221/2015-1; 158744/2018-7National Council for Scientific and Technological Development (CNPq)National Council for Scientific and Technological Development (CNPq) [141221/2015-1, 158744/2018-7]; Spanish Ministry of Science, Innovation and Universities BaCTeria Project [MAT2017-86163-C2-R

Polyurethane fibrous membranes tailored by rotary jet spinning for tissue engineering applications

Polymeric membranes have gained popularity as fibrous structures for tissue regeneration. This research focuses on the rotary jet spinning (RJS) process combined with a polymer as a strategy for designing membranes. To this end, RJS-polyurethane (RJS-PU) membranes with different microstructures were produced. Considering the effects of solution properties on fiber production, the viscosity of PU solutions was evaluated. Membrane morphology was studied based on scanning electron microscopy and 2D fast Fourier transform analysis. The chemical and thermal properties were characterized by Fourier-transform infrared spectroscopy and thermogravimetric analysis, respectively. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Live/Dead cell assays were performed to determine the material cytotoxicity by assessment of the profile of proliferation and cell viability. The results indicated that the combination of PU and RJS was an effective one for the production of fibrous structures for tissue engineering applications, demonstrating good compatibility with the cultured osteoblastic cell line13711FAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo2017/13273‐6; 2008/57860‐

An assessment of biomedical CoCrMo alloy fabricated by direct metal laser sintering technique for implant applications

CoCrMo alloys have been used for several decades in implantable devices due to their favourable mechanical properties, low wear rate in addition to good biocompatibility and high corrosion resistance. These alloys are conventionally produced via casting and/or forging route, however additive manufacturing techniques being recently employed in their fabrication. In this work, CoCrMo samples were produced by direct metal laser sintering additive manufacturing process. The microstructure and surface composition were examined employing scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy (XPS). The corrosion resistance was measured in 0.14 M sodium chloride solution and in phosphate buffered solution (PBS) both with and without addition of albumin at pH 7.4 and 37 degrees C. For this, potentiodynamic tests in addition to electrochemical impedance spectroscopy were employed. The studied CoCrMo alloy exhibits a good corrosion resistance in solutions tested being the highest in PBS solution without albumin addition. The XPS analysis showed that the passive film composition and its thickness are not modified by the adsorbed layer. Microstructural analysis revealed occurrence of strain-induced martensitic transformation107COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP50/20112016/09350-2; 2007/54829-

Poliuretano A Base De AÇai E Uso Para BiofabricaÇÃo De Dispositivos MÉdicos

POLIURETANO A BASE DE AÇAÍ E USO PARA BIOFABRICAÇÃO DE DISPOSITIVOS MÉDICOS. O presente pedido de patente de invenção refere-se a espumas rígidas de poliuretano poroso e uso da mesma como biomaterial de suporte para crescimento celular (scaffold). A invenção também se refere ao processo de produção das espumas rígidas de poliuretano citadas. Mais espeficamente, a espuma rígida de poliuretano poroso é produzida pela reação entre um poli-isocianato alifático e um poliol de base natural e renovável, o açaí, resultando em um produto apropriado para biomateriais. Uma das grandes vantagens da invenção é que o poliol do açaí possui numerosos tipos de fitoquímicos como antocianinas e flavonóides, atualmente considerados como "alimentos funcionais" com potencial para atividades anti-inflamatórias, anti-oxidantes e antitrombogênicas. Como o poliol é de base natural e renovável o poliuretano proposto possui grande aplicabilidade em biofabricação.BRPI1105296 (A2)C08G18/10C08G18/02BR2011PI05296C08G18/10C08G18/0