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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

Aplica??o de polifenois na dentina humana : estudo in vitro da morfologia interfacial e da resist?ncia de uni?o

Paludo, Tamara 10 January 2018 (has links)
Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-03-19T17:50:17Z No. of bitstreams: 1 TAMARA_PALUDO_DIS.pdf: 786437 bytes, checksum: 24d142989a1f4e1aac8bb4a9d2a1548c (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-04-04T11:42:36Z (GMT) No. of bitstreams: 1 TAMARA_PALUDO_DIS.pdf: 786437 bytes, checksum: 24d142989a1f4e1aac8bb4a9d2a1548c (MD5) / Made available in DSpace on 2018-04-04T11:50:01Z (GMT). No. of bitstreams: 1 TAMARA_PALUDO_DIS.pdf: 786437 bytes, checksum: 24d142989a1f4e1aac8bb4a9d2a1548c (MD5) Previous issue date: 2018-01-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / (Artigo 1 Effect of a collagen stabilizing acid conditioner on adhesion to enamel and dentin) The aim was to evaluate the effect of different concentrations of phosphoric acid with grape seed extract (GSE) on the enamel acid etching, on the immediate bond strength to enamel, and on the bond strength to dentin after 12 months storage. Three different phosphoric acid formulations with GSE were obtained: GSE5 - 5% phosphoric acid + 20% ethanol + 2% GSE; GSE10 -10% phosphoric acid + 20% ethanol + 2% GSE; GSE20 - 20% phosphoric acid + 20% ethanol + 2% GSE; GC (control) - 37% phosphoric acid. The enamel and dentin surfaces of third molars, extracted for therapeutic reasons, were etched with 37% phosphoric acid for 15 s, and with the modified acids for 30 s. The acid was rinsed, followed by application of Adper Scotchbond Multipurpose adhesive system, and a block of composite resin was built. In enamel, the etching pattern was evaluated by scanning electron microscopy (SEM) and the bond strength was evaluated by conventional tensile test. In dentin, the microtensile bond strength (?TBS) was evaluated after 24 h and 1 year of storage. SEM images showed that GSE5 caused a more superficial enamel etching. According to ANOVA and Tukey?s test, enamel bond strength did not differ significantly between GC (49.00 MPa), GSE5 (42.78 MPa), GSE10 (51.55 MPa) and GSE 20 (36.18 MPa) (p> 0.05).According to two-way ANOVA and Tukey?s test, the interaction of factors (treatment x storage time) was significant (p=0.0001). At the 24 h of storage, GC (28.43 MPa) obtained the highest ?TBS, and did not differ significantly from GSE20 (24.11 MPa). GC and GSE20 were significantly higher to the others (p<0.05).The GSE10 (17.53 MPa) and GSE5 (16.75 MPa) did not differ significantly from each other. At the 12 months of storage, there was no significant difference in ?TBS between GC (17.71 MPa), GSE5 (20.97 MPa), GSE10 (17.59 MPa) and GSE20 (18.52 MPa). Only GSE5 and GSE10 did not significantly decrease ?TBS after 12 months of storage. It was concluded that GSE5 caused a more superficial enamel etching pattern in relation to the acid concentrations at 37%, 20% and 10%. However, there was no significant difference in the bond strength to enamel among the four concentrations. GSE5 and GSE10 promoted stability of the bond strength to dentin after 12 months of storage. (Artigo 2 Effect of phosphoric acid with polyphenols on dentin collagen : Atomic force microscopy study) Objective: The aim was of this study to evaluate the effect of different concentrations of phosphoric acid with grape seed extract (GSE) on the structure of the collagen fibrils of dentin. Materials and methods: Samples (0.3 mm thickness and 8 mm diameter) of the middle third of the coronal dentin of sound human molars were obtained. Half of the dentin of each tooth was etched with phosphoric acid (5%, 10%, or 20%) for 30 s, and the other half was etched with its corresponding phosphoric acid with 2% GSE for 30 s. The dentin of each sample was observed using an Atomic Force Microscope (AFM). Results: AFM images showed that phosphoric acid at concentrations of 5%, 10% and 20% demineralized the dentin and exposed the collagen fibrils and their pattern of periodicity. Phosphoric acid at each concentration with 2% GSE changed the collagen fibril periodicity, and the collagen fibrils formed globular structures. This change was more significant in dentin treated with 5% phosphoric acid and less significant with 20% phosphoric acid. Conclusions: The use of 5% phosphoric acid with 2% GSE produced denser collagenous globular structures. This conformational change in the collagen can make it more mechanically and enzymatically resistant. / (Artigo 1 Efeito de um condicionador ?cido estabilizador de col?geno na ades?o ao esmalte e ? dentina) O objetivo foi avaliar o efeito de diferentes concentra??es de ?cido fosf?rico com extrato de semente de uva (GSE) no padr?o de condicionamento ?cido em esmalte, na resist?ncia de uni?o imediata ao esmalte e ap?s 12 meses de armazenamento em dentina. Tr?s diferentes formula??es de ?cido fosf?rico com GSE foram obtidas: GSE5 - 5% de ?cido fosf?rico + 20% de etanol + 2% de GSE; GSE10 -10% de ?cido fosf?rico + 20% de etanol + 2% de GSE; GSE20 - 20% de ?cido fosf?rico + 20% de etanol + 2% de GSE; GC (controle) - ?cido fosf?rico 37%. As superf?cies do esmalte e da dentina de dentes terceiros molares, extra?dos por raz?es terap?uticas, foram condicionadas com ?cido fosf?rico 37% por 15 s e com os ?cidos modificados por 30 s, seguido de lavagem e aplica??o do sistema adesivo Adper Scotchbond Multiuso (convencional de tr?s passos) e da constru??o de um bloco em resina composta. Em esmalte, o padr?o de condicionamento foi avaliado em microscopia eletr?nica de varredura (MEV) e a resist?ncia de uni?o foi avaliada pelo ensaio de tra??o convencional. Em dentina, a resist?ncia de uni?o ? microtra??o (R?T) foi avaliada ap?s 24 h e 12 meses de armazenamento. As imagens em MEV evidenciaram que o GSE5 causou um condicionamento mais superficial do esmalte. De acordo com ANOVA de 2 fatores e Tukey, a resist?ncia de uni?o ao esmalte n?o diferiu estatisticamente entre GC (49,00 MPa), GSE5 (42,78 MPa), GSE10 (51,55 MPa) e GSE20 (36,18 MPa) (p>0,05). De acordo com ANOVA de duas vias e Tukey, a intera??o tratamento x tempo de armazenamento foi significativa (p=0,0001). No tempo de armazenamento de 24 h, GC (28,43 MPa) obteve a maior R?T, n?o diferindo estatisticamente do grupo GSE20 (24,11 MPa), sendo ambos estatisticamente superiores aos demais (p<0,05). O grupo GSE10 (17,53 MPa) e o GSE5 (16,75 MPa) n?o diferiram estatisticamente entre si. No tempo de armazenamento de 12 meses, n?o houve diferen?a estat?stica na R?T entre o GC (17,71 MPa), GSE5 (20,97 MPa), GSE10 (17,59 MPa) e GSE20 (18,52 MPa). Apenas GSE5 e GSE10 n?o tiveram redu??o significativa da R?T ap?s 12 meses de armazenamento. Concluiu-se que o GSE5 causou um condicionamento mais superficial do esmalte em rela??o ?s concentra??es de 37%, 20% e 10%. No entanto, n?o houve diferen?a estat?stica nos valores de resist?ncia ? tra??o imediata ao esmalte entre as quatro concentra??es. GSE5 e GSE10 promoveram a estabilidade da resist?ncia de uni?o ? dentina ap?s 12 meses de armazenamento.
2

Avaliar a interfer?ncia do condicionamento ?cido com ?cido fosf?rico na resist?ncia de uni?o do sistema adesivo universal na dentina afetada por c?rie. / To assess the interference of acid etching with phosphoric acid on the bond strength of the universal adhesive system in dentin affected by caries

Pavanello, Renata Eliza 02 February 2018 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2018-03-15T13:19:19Z No. of bitstreams: 1 RENATA ELIZA PAVANELLO.pdf: 1818495 bytes, checksum: 584f82239d012d948febe192c32331a9 (MD5) / Made available in DSpace on 2018-03-15T13:19:20Z (GMT). No. of bitstreams: 1 RENATA ELIZA PAVANELLO.pdf: 1818495 bytes, checksum: 584f82239d012d948febe192c32331a9 (MD5) Previous issue date: 2018-02-02 / The aim of this paper was to evaluate the influence of acid etching on the bond strength of the universal adhesive system in caries-affected-dentin. For this experimental study, 40 erupted permanent third molars were selected at the Dental Clinic of the PUC-Campinas with Free and Informed Consent Term signed by the patients. Removal of the occlusal third with double - sided diamond disc and flat dentin surfaces obtained by sanding was done. The lesion of the caries was developed by microbiological method with S. mutans strain ATCC25175. The teeth were divided into 4 groups (n = 10): AF-I: phosphoric acid conditioning and application of the Universal Single Bond adhesive system - immediate microtensile test; AF-DC: phosphoric acid conditioning and application of the Universal Single Bond adhesive system and microtensile test after cariogenic challenge; SAF-I: application of the Universal Single Bond adhesive system without acid etching and immediate microtensile test and SAF-DC: application of the Universal Single Bond adhesive system without acid etching and microtensile test after carig?nico challenge. A composite resin block was made in the affected dentin. Each tooth / adhesive / resin block was sectioned with diamond discs coupled to the Isomet cutting machine in parallel planes obtaining test pieces in the shape of sticks, with a cross-sectional area of 1 mm2. Microtensile test was performed. Only adhesive / mixed fractures were considered for bond strength calculation. The results were evaluated by the Kruskal-Wallis test (Student-Newman-Keuls) and Friedman. The higher bond strength occurred in the groups in which the phosphoric acid conditioning was done (p <0.05). There was no significant difference in union strength after cariogenic challenge (p> 0.05). The type of fracture was predominantly adhesive. It was concluded that phosphoric acid caused increased bond strength of the Universal Single Bond adhesive system in caries affected dentin and the cariogenic challenge did not interfere in the bond strength of the Universal Single Bond adhesive system in dentin affected by caries. / O objetivo deste trabalho foi avaliar a interfer?ncia do condicionamento ?cido na resist?ncia de uni?o do sistema adesivo universal na dentina afetada por c?rie. Para este estudo de car?ter experimental foram selecionados 40 terceiros molares permanentes erupcionados com Termo de Consentimento Livre e Esclarecido assinado pelos pacientes na Cl?nica Odontol?gica da PUC-Campinas. Foi feita a remo??o do ter?o oclusal com disco diamantado dupla face e superf?cies dentin?rias planas obtidas atrav?s de lixamento. A les?o de c?rie foi desenvolvida pelo m?todo microbiol?gico com cepa padr?o S. mutans ATCC25175. Os dentes foram divididos aleatoriamente em 4 grupos (n=10): AF-I: condicionamento com ?cido fosf?rico e aplica??o do sistema adesivo Single Bond Universal - teste imediato de microtra??o; AF-DC: condicionamento com ?cido fosf?rico e aplica??o do sistema adesivo Single Bond Universal e teste de microtra??o ap?s desafio cariog?nico; SAF-I: aplica??o do sistema adesivo Single Bond Universal sem condicionamento ?cido e teste imediato de microtra??o e SAF-DC: aplica??o do sistema adesivo Single Bond Universal sem condicionamento ?cido e teste de microtra??o ap?s desafio carig?nico. Um bloco de resina composta Charisma foi confeccionado na dentina afetada. Cada bloco dente/adesivo/resina foi seccionado com discos diamantados acoplados a m?quina de corte Isomet em planos paralelos obtendo corpos de prova em forma de palitos, com ?rea de sec??o transversal de 1 mm2. Para realiza??o do teste de microtra??o. Apenas fraturas adesivas /mistas foram consideradas para c?lculo de resist?ncia de uni?o. Os resultados foram avaliados pelo teste Kruskal-Wallis (Student-Newman-Keuls) e Friedman. A maior resist?ncia de uni?o ocorreu nos grupos em que foi feito o condicionamento com ?cido fosf?rico (p<0.05). N?o houve diferen?a significante na resist?ncia de uni?o ap?s o desafio cariog?nico (p>0.05). O tipo de fratura predominante foi adesiva. Pode-se concluir que o ?cido fosf?rico acarretou aumento na resist?ncia de uni?o do sistema adesivo Single Bond Universal na dentina afetada por c?rie e o desafio cariog?nico n?o interferiu na resist?ncia de uni?o do sistema adesivo Single Bond Universal na dentina afetada por c?rie.

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