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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.
1

Rugosidade superficial e ades?o bacteriana em comp?sitos com nanopart?culas ap?s acabamento e polimento

Costa, Giovanna de F?tima Alves da 12 December 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-22T21:16:09Z No. of bitstreams: 1 GiovannaDeFatimaAlvesDaCosta_DISSERT.pdf: 9340416 bytes, checksum: b55d9a3f32743415d64d3bda38bbd9d5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-22T21:32:13Z (GMT) No. of bitstreams: 1 GiovannaDeFatimaAlvesDaCosta_DISSERT.pdf: 9340416 bytes, checksum: b55d9a3f32743415d64d3bda38bbd9d5 (MD5) / Made available in DSpace on 2016-08-22T21:32:13Z (GMT). No. of bitstreams: 1 GiovannaDeFatimaAlvesDaCosta_DISSERT.pdf: 9340416 bytes, checksum: b55d9a3f32743415d64d3bda38bbd9d5 (MD5) Previous issue date: 2014-12-12 / Objetivo: avaliar in vitro a rugosidade superficial e a ades?o bacteriana de comp?sitos nanoparticulados, ap?s serem submetidas a diferentes sistemas de acabamento e polimento. Materiais e M?todos Foram confeccionados 60 corpos de prova, distribu?dos em 6 grupos (n=10). Em todos os grupos foi utilizada tira matriz de poli?ster sobre a superf?cie das amostras, e cada tipo de resina foi submetido aos sistemas de acabamento e polimento: discos Sof-Lex Pop-On (3M ESPE, St.Paul, USA) e sistema AstropolTM (Ivoclar Vivadent,NY,USA), caracterizando o grupo experimental; o grupo controle n?o foi submetido a nenhum tipo de t?cnica de acabamento e polimento. A rugosidade m?dia (Ra) em ambos os grupos foi mensurada atrav?s de um rugos?metro (Taylor Hobson Brazil, Ltda., S?o Paulo, SP, Brazil) na configura??o de 0,25mm (cut off) e as imagens da superf?cie obtidas com fotomicrografias captadas por um microsc?pio eletr?nico de varredura (MEV) com aumento de 500 vezes. A ades?o bacteriana foi avaliada por meio da leitura de espectrofotometria com configura??o de 570?m. Os resultados foram submetidos ? an?lise de vari?ncia (ANOVA dois fatores. Resultados: Foram encontradas diferen?as estat?sticas significativas entre os grupos quanto ? rugosidade e ? ades?o bacteriana. Para a resina Filtek Z350 XT houve diferen?as entre os sistemas de acabamento e polimento testados, onde o sistema que apresentou menor rugosidade superficial foi o Sof-lex Pop-On. Para a resina IPS Empress Direct, o sistema de acabamento e polimento Astropol, obteve menores resultados de rugosidade superficial. Quanto ? ades?o bacteriana, o menor valor de densidade ?ptica para a resina Filtek Z350 XT foi para o grupo que utilizou o sistema de acabamento e polimento Sof-Lex Pop-On e para a resina IPS Empress Direct o grupo que utilizou o sistema Astropol. Al?m disso, verificou-se uma correla??o positiva entre a rugosidade superficial e ades?o bacteriana nas superf?cies polidas (r = 0,612, p <0,001) Conclus?es: a rugosidade superficial e a ades?o bacteriana est?o estreitamente relacionadas. O sistema de acabamento e polimento Sof-Lex Pop-On est? mais indicado para a resina nanoparticulada Filtek Z350 XT e o sistema de acabamento e polimento Astropol para a resina nanoh?brida IPS Empress Direct. / Objective: To evaluate in vitro the surface roughness and bacterial adhesion of nanoparticle composites, after being subjected to different finishing and polishing systems. Materials and Methods: 66 specimens were prepared, and 30 with Filtek Z350 XT (3M ESPE, USA) and 30 with the resin IPS Empress Direct (Ivoclar Vivadent, USA), divided into 6 groups (n = 10 ). Six specimens were prepared for analysis in scanning electron microscopy (SEM) .Each kind of resin was subjected to finishing and polishing systems: Sof-Lex Pop-On discs (3M ESPE, USA) and AstropolTM system (Ivoclar Vivadent , USA), featuring the experimental group. The control group did not undergo any kind of finishing and polishing technique. The average roughness (Ra) in both groups was measured using a roughness in the setting of 0.25 mm (cut off) and surface images obtained with photomicrographs taken with a scanning electron microscope (SEM) magnified 500 times. Bacterial adherence was evaluated by determining the absorbance (OD) of the suspension of adhered cells by spectrophotometer at 570 nm. The results were submitted for analyzed with 2-way ANOVA at ?=.05 and Tukey multiple comparison tests. Results: Statistically significant differences were found between the groups in terms of roughness and bacterial adhesion. Filtek Z350 XT for resin were no differences between the tested finishing and polishing systems, where the system of lowest surface roughness was the Sof-Lex Pop-On. To the resin IPS Empress Direct, the finishing and polishing system Astropol, had lower results of surface roughness. As for bacterial adhesion, the lowest optical density value for Filtek Z350 XT was for the group that used the finishing and polishing system Sof-Lex Pop-On and the resin IPS Empress Direct the group that used the Astropol system. In addition, there was a positive correlation between surface roughness and bacterial adhesion on polished surfaces (r = 0.612) Conclusions: surface roughness and bacterial adhesion are closely related. The finishing and polishing Sof-Lex Pop-On system is more suitable for nanoparticulate Filtek Z350 XT and the finishing and polishing system Astropol for resin nanoh?brida IPS Empress Direct.
2

Efeito das varia??es de pH e do ?cido g?strico na superf?cie de resinas compostas de incremento ?nico

Somacal, Deise Caren 10 January 2018 (has links)
Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-03-14T13:07:26Z No. of bitstreams: 1 DEISE_CAREN_SOMACAL_DIS.pdf: 3724441 bytes, checksum: 7f1a32555f56a0c3c48079417ccb5782 (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-03-21T13:30:22Z (GMT) No. of bitstreams: 1 DEISE_CAREN_SOMACAL_DIS.pdf: 3724441 bytes, checksum: 7f1a32555f56a0c3c48079417ccb5782 (MD5) / Made available in DSpace on 2018-03-21T13:51:59Z (GMT). No. of bitstreams: 1 DEISE_CAREN_SOMACAL_DIS.pdf: 3724441 bytes, checksum: 7f1a32555f56a0c3c48079417ccb5782 (MD5) Previous issue date: 2018-01-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / (Artigo 1 Efeito das varia??es do pH na superf?cie de resinas compostas de incremento ?nico) Aim: To evaluate, in vitro, quantitatively and qualitatively, the effect of pH variations on surface roughness (Ra) and bacterial adhesion (Cn) of Bulk-Fill composite resins followed by simulated toothbrushing. Materials and Methods: Thirty samples of each composite resin were obtained: G1 (control): Z250; G2: Filtek Bulk-Fill (FTK); G3: Tetric N Ceram Bulk-Fill (TTC); G4: Aura Bulk-Fill (AUR). After 24 h, the samples were polished and then alternated by DES/RE solutions for 15 cycles of 24 h each at 37?C. Then, the samples were submitted to simulated toothbrushing. The Ra and Cn measurements were quantitatively analyzed in three stages: after polishing (Ra0 and Cn0), after pH cycles (Ra1 and Cn1) and after simulated toothbrushing (Ra2 and Cn2). Measurements on new samples submitted only to simulated toothbrushing were also performed (Ra* and Cn*). The Ra values were submitted to two-way ANOVA, followed by the Tukey?s test (?=0.05). The Kruskal-Wallis test followed by multiple comparisons was applied for Cn analysis. Surface topography and bacterial adhesion were observed by Scanning Electron Microscopy (SEM). Results: Z250, FTK and TTC showed no significant change in Ra regardless of the treatment performed, except for AUR which obtained superior Ra at Ra2 (p <0.05). In the bacterial count, FTK differed from the others in Cn0 and Cn1. In Cn2 there was no difference between the composite resins. Only after Cn*, the Z250 differed from all other materials. SEM images showed cracking and exposure of fillers in Ra1, with detachment of the exposed fillers. Microcavities were observed in all composite resins in Ra2. Bacterial adhesion occurred in all composite resins regardless of the treatment. There was greater bacterial adhesion in Cn1 for Z250 and FTK. Conclusion: The pH cycles did not alter the Ra of composite resins Z250, FTK, TTC and AUR. Simulated toothbrushing after pH cycles caused Ra increase only for AUR, and reduced bacterial adhesion in Z250 and FTK composite resins. There was degradation of the surface of all composite resins, as well as bacterial adhesion. (Artigo 2 Effect of gastric acid on the surface of bulk-fill composite resins) Aim: To evaluate, in vitro, quantitatively and qualitatively, the effect of gastric acid on surface roughness and bacterial adhesion in Bulk-Fill composite resins followed by simulated toothbrushing. Materials and Methods: 30 samples of each Bulk-Fill composite resin were obtained: G1 (control): Z250; G2: Filtek Bulk- Fill (FTK); G3: Tetric N-Ceram Bulk-Fill (TTC); G4: Aura Bulk-Fill (AUR). The samples were polished after 24 h and immersed in 10 ml of gastric acid for 24 h at 37?C. Following, the samples were submitted to simulated toothbrushing. Ra and Cn were obtained in three different stages: initial (Ra0 and Cn0), after gastric acid (Ra1 and Cn1) and after gastric acid and simulated toothbrushing (Ra2 and Cn2). Additional samples were submitted to the simulated toothbrushing test only and received the same measurements (Ra* and Cn*).Two-way ANOVA was used to evaluate Ra, followed by the Tukey test. Regarding the Cn analysis, the Kruskal-Wallis test was used, followed by multiple comparisons. The significance level was of 5%. Results: Z250 and FTK had a significant increase in surface roughness in Ra1. In Ra2, the four composite resins did not significantly differ from Ra0, but there was a significant reduction of the means in Ra2 of Z250 and FTK compared to Ra1. For Cn, Z250 and FTK allowed an increased biofilm accumulation in comparison with TTC and AUR. SEM images showed crack formation and exposure of fillers in Ra1, occurring detachment of the exposed fillers. Microcavities were observed in all composite resins in Ra2. Bacterial adhesion occurred in all composite resins regardless of the treatment. There was higher bacterial adhesion in Cn1, followed by reduction of bacterial adhesion in Cn2 for all tested materials, except for AUR. Conclusion: Gastric acid increased the surface roughness of Z250 and FTK composite resins, as well as promoted higher bacterial accumulation compared to TTC and AUR composite resins. There was degradation of the surface of all composite resins, as well as bacterial adhesion. / (Artigo 1 Efeito das varia??es do pH na superf?cie de resinas compostas de incremento ?nico) Objetivo: Avaliar, in vitro, de forma quantitativa e qualitativa, o efeito das varia??es de pH na rugosidade superficial (Ra) e na ades?o bacteriana (Cn) de resinas compostas de incremento ?nico seguido de escova??o simulada. Materiais e M?todos: Trinta amostras de cada resina composta (5mm de largura e 4mm de altura) foram obtidas -G1(controle): Z250; G2: Filtek Bulk-Fill (FTK); G3: Tetric N Ceram Bulk-Fill (TTC); G4: Aura Bulk-Fill (AUR). Ap?s 24 h, as amostras foram polidas e ent?o alternaram por solu??es DES/RE por 15 ciclos de 24 h cada a 37?C. Na sequ?ncia foram submetidas ? escova??o simulada. As medidas Ra e Cn foram analisadas quantitativamente em tr?s etapas: ap?s polimento (Ra0 e Cn0), ap?s ciclos de pH (Ra1 e Cn1) e ap?s escova??o simulada (Ra2 e Cn2). Medi??es em novas amostras submetidas apenas ? escova??o simulada foram realizadas (Ra* e Cn*). Para an?lise dos dados de Ra foi utilizada a ANOVA de dois fatores, seguida do teste de Tukey (?=0,05). O teste de Kruskal-Wallis seguido de compara??es m?ltiplas foi utilizado para an?lise de Cn. A topografia superficial e a ades?o bacteriana foram observadas em Microscopia Eletr?nica de Varredura (MEV). Resultados: Z250, FTK e TTC n?o tiveram altera??o significativa de Ra independente do tratamento realizado, com exce??o da AUR que obteve Ra superior em Ra2 (p<0,05). Em Cn, FTK diferiu das demais em Cn0 e Cn1. Em Cn2 n?o houve diferen?a entre as resinas compostas. Apenas ap?s Cn*, a Z250 diferiu dos outros materiais. Imagens em MEV evidenciaram forma??o de trincas e exposi??o de part?culas de carga em Ra1, com desprendimento das part?culas expostas. Houve forma??o de microcavidades em todas as resinas compostas em Ra2. Ocorreu ades?o bacteriana em todas as resinas compostas independente do tratamento. Houve maior ades?o bacteriana em Cn1 para Z250 e FTK. Conclus?o: Os ciclos de pH n?o alteraram Ra das resinas compostas Z250, FTK, TTC e AUR. A escova??o simulada ap?s os ciclos de pH causou aumento de Ra apenas para AUR e reduziu a ades?o bacteriana nas resinas compostas Z250 e FTK. Houve degrada??o da superf?cie de todas as resinas compostas, assim como ades?o bacteriana. (Artigo 2 Efeito do ?cido g?strico na superf?cie de resinas compostas de incremento ?nico) Objetivo: Avaliar de forma quantitativa e qualitativa o efeito do ?cido g?strico na rugosidade superficial e na ades?o bacteriana nas resinas compostas de incremento ?nico (Bulk-Fill) seguido de escova??o simulada. Materiais e M?todos: Trinta amostras de cada resina composta (di?metro de 5mm e altura de 4mm) foram obtidas - G1(controle): Z250; G2: Filtek Bulk-Fill (FTK); G3: Tetric N-Ceram Bulk-Fill (TTC); G4: Aura Bulk-Fill (AUR). As amostras foram confeccionadas e polidas ap?s 24 h. As amostras foram imersas em 10 ml de ?cido g?strico durante 24 h em 37?C. Na sequ?ncia, as resinas compostas foram submetidas ? escova??o simulada. As medidas de Rugosidade Superficial (Ra) e Contagem bacteriana (Cn) foram obtidas em tr?s diferentes etapas: inicial (Ra0 e Cn0), ap?s ?cido g?strico (Ra1 e Cn1) e ap?s ?cido g?strico e escova??o simulada (Ra2 e Cn2). Amostras adicionais foram submetidas unicamente ao teste de escova??o simulada e receberam as mesmas medi??es (Ra* e Cn*). ANOVA de dois fatores foi utilizada para avalia??o de Ra, seguida do teste de Tukey. Para an?lise de Cn foi utilizado o teste de Kruskal-Wallis, seguido de compara??es m?ltiplas. O n?vel de signific?ncia foi de 5%. A topografia superficial e a ades?o bacteriana foram observadas em microscopia eletr?nica de varredura (MEV). Resultados: Z250 e FTK tiveram aumento significativo na rugosidade superficial em Ra1. Em Ra2, as quatro resinas compostas n?o diferiram estatisticamente de Ra0, por?m houve redu??o significativa das m?dias em Ra2 da Z250 e FTK em compara??o a Ra1. Para Cn, Z250 e FTK permitiram maior ac?mulo de biofilme em rela??o ? TTC e AUR. Imagens em MEV evidenciaram forma??o de trincas e exposi??o de part?culas de carga em Ra1, ocorrendo desprendimento das part?culas de carga expostas. Microcavidades foram observadas em todas as resinas compostas em Ra2. A ades?o bacteriana ocorreu em todas as resinas compostas independente do tratamento. Houve maior ades?o bacteriana em Cn1, seguida de redu??o da ades?o bacteriana em Cn2 para todos os materiais testados, exceto pela AUR. Conclus?o: O ?cido g?strico aumentou a rugosidade superficial das resinas compostas Z250 e FTK, assim como promoveu maior ac?mulo bacteriano em rela??o ?s resinas compostas TTC e AUR. Houve degrada??o da superf?cie de todas as resinas compostas, assim como ades?o bacteriana.

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