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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Avaliação da influência do sistema de polimento na topografia superficial de diferentes resinas compostas

Correia, Ayla Macyelle de Oliveira 29 January 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Several polishing protocols have been assessed for their effect on the surface roughness of restorative materials. However, the effect of polishing systems on surface roughness depend on the composite used. The aim of this study was to evaluate the influence of two different polishing systems (Diamond Pro, FGM - DP; Jiffy® Polishers, Ultradent Products - JP) combined to three composites: nanoparticle (Filtek ™ Z350 XT, 3M / ESPE), nanohybrid (IPS Empress Direct, Ivoclar Vivadent Ltd.) and microhybrid (Vit-l-escence®, Ultradent Products). Fifty-four pecimenss were prepared in a metallic matrix (10 mm x 2 mm) and polymerized under a polyester strip. The specimens were identified and randomly distributed into six groups (n = 9) in accordance to the polishing system. Surface roughness was measured at baseline E0 (polyester strip), E1 (diamond burs), E2D (Diamond Pro) and E2J (Jiffy® polishers) by a profilometer. Data were collected and analyzed. To qualitatively analyze the surface, one specimen from each group was analyzed by atomic force microscopy (AFM). According to the Paired t-test (p <0.05), there was no significant difference between the roughness values obtained in E0 and E2D for nanoparticle composites (p = 0.463) and nanohybrid (p = 0.423). However, for microhybrid composite, using both polishing systems led to significantly rougher surfaces than E0. The AFM showed that surface roughness is related to particle morphology. It was concluded that the surface roughness is dependent on composite and polishing system. / Diversos protocolos de polimento têm sido avaliados quanto ao seu efeito sobre a rugosidade superficial de materiais restauradores. No entanto, o efeito dos sistemas de polimento pode variar a rugosidade superficial de acordo com o compósito utilizado. Desta forma, o objetivo deste estudo foi avaliar a influência de dois diferentes sistemas de polimento (Diamond Pro, FGM; Jiffy® Polishers, Ultradent Products) na rugosidade superficial de três resinas compostas: nanoparticulada (Filtek™ Z350 XT, 3M/ESPE), nanohíbrida (IPS Empress Direct, Ivoclar Vivadent Ltda) e microhíbrida (Vit-l-escence®, Ultradent Products). Cinquenta e quatro amostras foram confeccionadas em uma matriz metálica (10 mm x 2 mm) e polimerizadas contra uma tira de poliéster. Em seguida, as amostras foram identificadas e distribuídas aleatoriamente em seis grupos (n=9) de acordo com a resina composta e o sistema de polimento a ser utilizado. Para cada amostra, a rugosidade superficial foi mensurada em E0 (baseline - tira de poliéster), E1 (pontas diamantadas), E2DP (Diamond Pro) ou E2JP (Jiffy® Polishers) por meio de um rugosímetro Mitutoyo SJ-410. Os dados encontrados foram coletados e analisados em software IBM SPSS Statistics, versão 21. Para caracterização da superfície, uma amostra de cada grupo foi analisada em microscópio de força atômica (MFA), modelo Agilent 5500. Segundo o teste T Pareado (p<0,05), não houve diferença significativa entre os valores de rugosidade obtidos em E0 e E2DP para as resinas compostas nanoparticulada (p=0,463) e nanohíbrida (p=0,423). Contudo, para a resina composta microhíbrida, a utilização de ambos os sistemas de polimento provocaram superfícies significativamente mais rugosas do que em E0. As observações de MFA confirmaram que a rugosidade da superfície está relacionada com a morfologia da partícula. Concluiu-se que a rugosidade da superfície foi afetada pelo tipo de compósito e sistema de polimento.
32

Comparación in vitro de la rugosidad superficial de resinas Bulk Fill sometidos a diferentes sistemas de pulidos / In Vitro comparison of the surface roughness of Bulk Fill resins using different polishing systems

Flores Angulo, Maricielo, Julca Chávez, Stefany Christel 07 September 2020 (has links)
Objetivo: Comparar in vitro la rugosidad superficial de resinas Bulk Fill sometidos a diferentes sistemas de pulido. Materiales y métodos: Noventa especímenes de resinas compuestas: Tetric® N-Ceram Bulk Fill (TNC), Filtek™ Bulk Fill (FB) y Opus Bulk Fill (OBF) fueron divididos en 9 grupos (n=10). Cada grupo fue sometido a un sistema de pulido: Cauchos Politip (CP), Discos Sof-lex™ (DS) y Discos Diamond Pro (DDP). La rugosidad superficial inicial y final fue evaluada mediante un rugosímetro. Los datos fueron analizados mediante estadística descriptiva (media ± d.e) y para la comparación de diferencias de rugosidad inicial y final se utilizó la prueba de Kruskal Wallis (p<0.05). Resultados: La rugosidad superficial inicial (media + d.e, CP/DS/DDP) fue: TNC (1.23± 1.30µm/0.94±0.53µm/0.90±0.57µm); FB (0.53±1.29µm/0.59±0.54µm/0.63±0.26µm) y OBF (0.74±0.50µm/0.96±0.62µm/0.65±0.25µm). La rugosidad final fue: TNC (0.19± 0.04µm/0.32±0.23µm/0.28±0.22µm); FB (0.29±0.17µm/0.22±0.19µm/0.25±0.19µm) y OBF (0.15±0.05µm/0.26±0.24µm/0.20±0.14µm). No se encontraron diferencias estadísticamente significativas entre la rugosidad inicial y la rugosidad final TNC (p=0.479); FB (p=0.163) y OBF (p=0.919). Conclusión: Existe una disminución en los valores de rugosidad superficial de las resinas Bulk Fill evaluadas después de ser sometidas a tres sistemas de pulidos. / Aim: To compare in vitro the surface roughness of Bulk Fill resins using different polishing systems. Materials and methods: Ninety specimens: Tetric® N-Ceram Bulk Fill (TNC), Filtek™ Bulk Fill (FB) and Opus Bulk Fill (OBF) were divided into 9 groups (n=10). Each group was polished using a different polishing system: Politip Polishers (PP), Sof-lex Polishing Discs™ (SPD) and Diamond Pro Sandpaper Disk (DPSD). The initial and final roughness were assessed using a profilometer. The results were analyzed using descriptive statistics (mean ±s.d) and for the comparison of differences in initial and final roughness was analyzed using the Kruskal Wallis test (p<0.05). Results: The initial surface roughness (mean ± s.d, PP/SPD/DPSD) was: TNC (1.23 ±1.30um/0.94±0.53um/0.90±0.57um); FB (0.53±1.29um/0.59±0.54um/0.63±0.26um) and OBF (0.74±0.50um/0.96±0.62um/0.65±0.25um). The final surface roughness was: TNC (0.19±0.04um/0.32±0.23um/0.28±0.22um); FB (0.29±0.17um/0.22±0.19um/0.25±0.19um) and OBF (0.15±0.05um/0.26±0.24um/0.20±0.14um). There were no significant differences between the initial and the final roughness measurements: TNC (p=0.479); FB (p=0.163) and OBF (p=0.919). Conclusion: There is a minor decrease in the surface roughness measurements of the Bulk Fill resins after using three different polishing systems. / Tesis

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