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Nowadays, researches have been investigated new materials for biomedical applications. The aim of this study iso optimize the behavior of the material / biological environment interface. Among the most used materials are titanium and its alloys due to properties such as resistance to corrosion and biocompatibility. Studies have shown cellular behavior can be influenced by surface morphology. Therefore, the objective of this study was to associate the deposition of PCL polymer fibers with the growth of TiO2 nanotubes on the surface of the Ti-30Ta alloy for biomedical applications. The electrospinning process was used for the production of 200nm polymer nanofibers. The use of biocompatible polymers for the viability of cell growth is a promising alternative to improve osseointegration. Characterization techniques such as scanning electron microscopy (SEM-FEG) were used to investigate the surface of the samples. Adult stem cells derived from human adipose tissue (ADSC) were also used to study the cellular response of these biomaterials. Cell viability was determined by the Cell Titer-Blue assay after 1 and 7 days. The results indicated the nanoarchitecture of the nanostructures in the micro-topography has a is a promising in the biomedical field. En los últimos años, se han llevado a cabo varias investigaciones en busca del desarrollo de materiales para aplicaciones biomédicas. Y uno de los objetivos de estos estudios es optimizar el comportamiento de la interfaz material / entorno biológico. Entre los materiales más utilizados se encuentran el titanio y sus aleaciones debido a sus propiedades como la resistencia a la corrosión y la biocompatibilidad. Los estudios han encontrado que el comportamiento celular puede verse influenciado por los cambios en la morfología de la superficie. Por lo tanto, el objetivo de este estudio fue asociar la deposición de fibras poliméricas de PCL con el crecimiento de nanotubos de TiO2 en la superficie de la aleación Ti-30Ta para aplicaciones biomédicas. El proceso de electrohilado se utilizó para la producción de nanofibras de polímero de 200 nm, debido en gran parte al mayor interés en las propiedades y tecnologías a nanoescala. El uso de polímeros biocompatibles para la viabilidad del crecimiento celular es una alternativa prometedora para mejorar la osteointegración. Se utilizaron técnicas de caracterización como la microscopía electrónica de barrido (SEM-FEG) para investigar la superficie de las muestras. Las células madre adultas derivadas del tejido adiposo humano (ADSC) también se utilizaron para estudiar la respuesta celular de estos biomateriales. La viabilidad celular se determinó mediante el ensayo Cell Titer-Blue después de 1 y 7 días. Los resultados indicaron que los cambios en la nanoarquitectura de las características morfológicas de las nanoestructuras en la micro-topografía, pueden ser prometedores en el campo biomédico debido a la modulación de la respuesta celular. Nos últimos anos, diversas pesquisas têm sido realizadas buscando o desenvolvimento de materiais para aplicações biomédicas. E, um dos objetivos desses estudos, é otimizar o comportamento da interface material/meio biológico. Dentre os materiais mais utilizados, estão o titânio e suas ligas devido às suas propriedades como resistência à corrosão e biocompatibilidade. Estudos constataram que o comportamento celular pode ser influenciado por alterações na morfologia das superfícies. Dessa maneira, o objetivo deste estudo foi associar a deposição de fibras poliméricas de PCL com o crescimento de nanotubos de TiO2 na superfície da liga Ti-30Ta para aplicações biomédicas. O processo de eletrofiação foi usado para a produção de nanofibras de polímero com 200 nm, devido em grande parte, ao aumento do interesse em propriedades e tecnologias em nanoescala. O uso de polímeros biocompatíveis para a viabilidade do crescimento celular é uma alternativa promissora para melhorar a osseointegração. Técnicas de caracterização como microscopia eletrônica de varredura (MEV-FEG) foi usado para investigar a superfície das amostras. Também foram utilizadas células-tronco adultas derivadas de tecido adiposo humano (ADSC) para estudar a resposta celular desses biomateriais. A viabilidade celular foi determinada pelo ensaio Cell Titer-Blue após 1 e 7 dias. Os resultados indicaram que as alterações na nanoarquitetura das características morfológicas das nanoestruturas na micro-topografia, podem ser promissoras no campo biomédico devido à modulação da resposta celular.

Made available in DSpace on 2022-04-30T09:53:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-03-01 This study evaluated the in vitro antibiofilm effect of 5 different commercial mouthwashes (Cepacol Traditional, Colgate Plax Fresh Mint, Listerine Cool Mint, Oral-B Complete, and Sensodyne) on Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Escherichia coli, and Pseudomonas aeruginosa. The cytotoxic effect of the mouthwashes on gingival fibroblasts was also analyzed. A colorimetric assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was used to investigate the viability of biofilms after 48 hours and gingival fibroblasts after 24 hours. The biofilms were exposed to the mouthwashes for 2 different lengths of time: T1, the time recommended by the manufacturer (30 or 60 seconds); and T2, double the recommended time (60 or 120 seconds). All antiseptic mouthwashes caused a significant reduction of biofilm (P < 0.05) as well as a significant reduction of viable gingival fibroblasts (P < 0.05) with both exposure times (T1 and T2). It can be concluded that the commercial mouthwashes demonstrated effective antibiofilm activity; they were more effective on bacteria than on C albicans. A significant cytotoxic effect on gingival fibroblasts was also observed. Department of Biosciences and Oral Diagnosis São Paulo State University Institute of Science and Technology Department of Biosciences and Oral Diagnosis São Paulo State University Institute of Science and Technology

Made available in DSpace on 2022-04-29T18:07:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-03-01 The purpose of this study was to evaluate the efficacy of different techniques for removal of combined calcium hydroxide [Ca(OH)2&] and chlorhexidine paste from root canals. Fifty single-rooted human teeth were prepared by oscillatory and rotary systems and filled with a paste of Ca(OH)2 and 2% chlorhexidine gel. After incubation for 14 days, the specimens were divided into 5 groups (n = 10), and the medication was removed by 1 of 5 different procedures. In group 1 (control), removal procedures involved a master apical file, foraminal debridement, and 5 mL of saline solution applied with the NaviTip irrigation needle. Group 2 was treated the same as group 1, but in addition 0.5 mL of 17% ethylenediaminetetraacetic acid was used for 3 minutes. In group 3, ultrasonic agitation was performed for 1 minute. Group 4 was treated as group 2, but the NaviTip FX needle was used for irrigation. In group 5, a master apical file, foraminal debridement, and 3-minute application of 5 mL of citric acid were used. After the root-cleaning procedures, the crowns were removed at the cementoenamel junction, and the roots were split longitudinally into halves. The success of intracanal medicament removal was observed under stereoscopic microscope and scanning electron microscope. Remnants of Ca(OH)2& were found in all experimental groups, regardless of the removal technique used. There was no statistically significant difference in cleanliness in the apical third of the root canal among groups 1, 2, and 3. Group 4 showed the best and group 5 the worst results with statistically significant differences. Overall, the NaviTip FX irrigation needle technique was more efficient in removing a Ca(OH)2-chlorhexidine paste from the root canal. Department of Restorative Dentistry Institute of Science and Technology São Paulo State University Department of Biosciences Department of Restorative Dentistry Institute of Science and Technology São Paulo State University

Made available in DSpace on 2022-04-28T21:24:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-01 Purpose: To quantify the amount of peroxide penetration from the pulp chamber to the external surface of teeth during the walking bleaching technique. Methods: Seventy-two bovine lateral incisors were randomly divided over five experimental groups and one control (n= 12 per group): (1) 35% hydrogen peroxide (HP); (2) 35% carbamide peroxide (CP); (3) sodium perborate (SP); (4) (HP+SP); (5) (CP+SP) and (6) Control (CG), deionized water. All groups were treated according to the walking bleach technique. After 7 days at 37°C in an acetate buffer solution, 100 μl violet leukocrystal coloring and 50 μl peroxidase was added, producing a blue stain that could be measured in a spectrophotometer and then converted into peroxide μg/ml. Results: G5 exhibited the greatest penetration, while G2 and G3 produced the lowest values. All bleaching agents penetrated from the pulp chamber to the external root surface. There was a direct correlation between the presence of oxidative agents and penetration potential. Sodium perborate in distilled water was less oxidative and appeared to be the least aggressive bleaching agent. Department of Endodontics São Paulo State University, Araraquara, SP Department of Biochemistry São Paulo State University, São José dos Campos, SP University of Connecticut, Farmington, CT Department of Endodontics São Paulo State University, Araraquara, SP Department of Biochemistry São Paulo State University, São José dos Campos, SP

Made available in DSpace on 2014-06-11T19:24:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-08-03Bitstream added on 2014-06-13T20:31:52Z : No. of bitstreams: 1 camargo_sea_me_sjc.pdf: 698707 bytes, checksum: 21ecc468a433f0633cef989558394cc9 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Acredita-se que a penetração de peróxido de hidrogênio através do esmalte e dentina pode causar danos à polpa. A proposta deste trabalho foi avaliar a quantidade de peróxido de hidrogênio no interior da câmara pulpar de dentes bovinos e humanos com ou sem restauração, após clareamento pela técnica de consultório. Os dentes foram seccionados 3mm à junção amelo-cementária e divididos em dois grupos: A (setenta terceiros molares humanos) e B (setenta incisivos laterais bovinos) que foram subdivididos em: A1 e B1 restaurados com resina composta (Esthetic-X, Dentsply), A2 e B2 com CIV (Vidrion-R, SSWhite), A3 e B3 com CIV modificado por resina (CIV-MR) (Vitremer, 3M); A4, A5, B4 e B5 não foram restaurados. No interior da câmara pulpar de todos os dentes foi colocado tampão acetato. Os subgrupos A1 a A4 e B1 a B4 foram expostos ao peróxido de hidrogênio 38% (Opalescence XtraBoost, Ultradent) por 40 min. Os subgrupos A5 e B5 permaneceram em água deionizada por 40 min. O tampão acetato foi transferido a um tubo de ensaio reagindo com corante violeta leucocristal e peroxidase. A densidade óptica da solução foi avaliada em espectrofotômetro, os valores de absorbância convertidos em microgramas de peróxido e submetidos aos testes de Dunnett, Kruskal-Wallis, ANOVA e Tukey (5%). Verificou-se maior penetração de peróxido nos dentes bovinos (0,79l0,61æg) e humanos (2,27l0,41æg) restaurados com CIV-MR. A penetração do agente clareador foi maior em dentes humanos para qualquer situação experimental. Concluiu-se que a penetração de peróxido depende do material restaurador e que dentes humanos são mais susceptíveis à penetração do agente clareador para o interior da câmara pulpar do que dentes bovinos. It is believe that externally applied bleachings agents could penetrate into the pulp chamber.This study was conducted to evaluate pulp chamber penetration of peroxide bleaching agent in human and bovine teeh, after office bleach technique. All the teeth were sectioned 3mm apical of the cemento-enamel junction and were divided into 2 groups: A (70 third human molars) and B (70 bovine lateral incisor) that were subdivided in: A1 and B1 restored using composite resin (Esthetic-X, Dentsply), A2 and B2 using glass ionomer cement (Vidrion-R, SSWhite), A3 and B3 using resin-modified glass ionomer cement (Vitremer, 3M); A4, A5, B4 and B5 were not restored. Acetate buffer was placed in the pulp chamber and the treatment agent was applied for 40 min as follow: A1 to A4 and B1 to B4 38% hydrogen peroxide exposure and A5 and B5 immersion into distilled water. The buffer solution was transferred to a glass tube where leuco crystal violet and horseradish peroxidase were added, producing a blue solution. The optical density of the blue solution was determined determined by spectrophotometer and converted into microgram equivalents of hydrogen peroxide. Data were submitted to ANOVA and Dunnett, Kruskal-Wallis, and Tukey tests (5%). A higher level of hydrogen peroxide penetrated into the pulp chamber in resin-modified glass ionomer cements groups, bovine (0,79l0,61æg) and human (2,27l0,41æg). The bleaching agent penetration was higher in human teeth for any experimental situation. The penetration of the hydrogen peroxide depend on restorative materials and that human teeth are more susceptible to penetration of bleaching agent into the pulp chamber than bovine teeth.