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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

A scanning electron microscope study of surface preparation and bonding to tooth tissue

Bloxham, Graeme P. January 1984 (has links)
Thesis (M.S.)--University of Michigan, Ann Arbor, 1984. / Typescript (photocopy). Includes bibliographical references (leaves 96-108). Also issued in print.
2

A scanning electron microscope study of surface preparation and bonding to tooth tissue

Bloxham, Graeme P. January 1984 (has links)
Thesis (M.S.)--University of Michigan, Ann Arbor, 1984. / Typescript (photocopy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 96-108).
3

The morphology of dental calculus

Friskopp, Johan. January 1984 (has links)
Thesis (doctoral)--Karolinska Institutet, Stockholm, 1984. / Extra t.p. with thesis statement inserted. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 34-42).
4

The morphology of dental calculus

Friskopp, Johan. January 1984 (has links)
Thesis (doctoral)--Karolinska Institutet, Stockholm, 1984. / Extra t.p. with thesis statement inserted. Includes bibliographical references (p. 34-42).
5

Influência do material obturador e agentes de limpeza pós-obturação na composição e morfologia da dentina radicular decídua / Influence of the filling pastes and post- filling cleaning agents in the composition and morphology in primary teeth root dentin

Benetello, Vanessa, 1983- 03 January 2012 (has links)
Orientador: Regina Maria Puppin-Rontani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-20T03:04:08Z (GMT). No. of bitstreams: 1 Benetello_Vanessa_M.pdf: 1255246 bytes, checksum: 803f9952085605139f802d3ac1bca050 (MD5) Previous issue date: 2012 / Resumo: O objetivo neste estudo foi avaliar o efeito de diferentes pastas obturadoras e agentes de limpeza sobre a dentina radicular de dentes decíduos, sobre: a estrutura molecular; e a morfologia de superfície da dentina radicular em dentes decíduos. Foram utilizadas 80 raízes de dentes decíduos anteriores extraídos por razões clínicas. As coroas foram seccionadas na junção cemento-esmalte e descartadas; e as raízes seccionadas no sentido longitudinal expondo os condutos radiculares, as quais foram planificadas e sonicadas. As raízes foram fixadas com resina composta para facilitar o manuseio, em seguida os condutos foram instrumentados com limas tipo K (15 a 35) e irrigados a cada troca de lima com hipoclorito de sódio a 0,5% + EndoPTC. Então, os espécimes foram distribuídos em 4 grupos de acordo com as pastas obturadoras (n=20): Controle-CP (sem obturação), Calen® espessada com óxido de zinco-CZ, Calcipex II®-CII, Vitapex®-V. Após a obturação, os espécimes foram armazenamentos por 7 dias. Após esse período, as pastas obturadoras foram removidas e os espécimes foram subdivididos em 4 grupos de acordo com os agentes de limpeza (n=5): Controle-CL (Sem limpeza), Etanol-E, Tergenform®-T, Ácido fosfórico-AF 35%...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The aim of this study was to verify the effect the different filling pastes and cleaning agents in primary dentin root, as: molecular structure and morphologic structure the surface of root dentin in primary teeth. For the study were used 80 anterior primary teeth roots extracted for clinical reasons. The crowns of the teeth were sectioned at cement enamel junction and discarded. The roots were separated longitudinally exposing the root canal, which were ground flat and sonicated. The specimens were fixed using composite resin to facilitate manipulation, and then they were prepared with K-type files size #15-35 and irrigated with of 0.5% sodium hypochlorite solution + EndoPTC cream. Thus, were divided into 4 groups (n=20) according to the filling pastes: Control (without filling), Calen® paste thickened with zinc oxide, Calcipex II®, Vitapex®. Then, the specimens were stored for seven days. After that, filling paste was removed and the specimens were subdivided into 4 cleaning agents groups (n=5): Control (without cleaning agents), Ethanol, Tergenform®, Phosphoric acid (35%)...Note: The complete abstract is available with the full electronic document / Mestrado / Odontopediatria / Mestre em Odontologia
6

Nucleation and growth of inorganic crystals at the organic-inorganic interface /

Dennis, Shelli R. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [140]-152).
7

A systems approach to recognition imaging : micropatterning and scanning force microscopy in the development of engineered biomaterials /

Garrison, Michael David, January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 290-319).
8

Analise "in vitro" da infiltração bacteriana e das adaptações na interface implante/conector protetico de sistemas de implantes endosseos / In vitro analysis of bacterial leakage and the implant/abutment interface adaptation of systems of endosseous implants

Oliveira, Greison Rabelo de 20 February 2006 (has links)
Orientador: Jose Ricardo Albergaria Barbosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-06T03:00:59Z (GMT). No. of bitstreams: 1 Oliveira_GreisonRabelode_M.pdf: 6578630 bytes, checksum: 77bd8ffe12b316550fcd3c7a8ce3dc9c (MD5) Previous issue date: 2006 / Resumo: O propósito deste estudo foi avaliar in vitro a contaminação bacteriana através da interface implante/conector protético de quatro marcas comerciais de implantes endósseos de titânio comercialmente puro, buscando correlacioná-la com as dimensões dos microespaços e das adaptações na referida interface. Todos os sistemas empregados foram de fabricação nacional. Para isto, utilizaram-se, 80 implantes de dois estágios cirúrgicos, com seus respectivos conectores protéticos, sendo 40 Hexágonos Externo e 40 Hexágono Interno, divididos em 08 grupos de acordo com as marcas comercias e tipo de hexágono, contendo 10 implantes cada grupo. Grupo 1HE (10 implantes HE Master Screw®) e grupo 1HI (10 implantes HI Master Conect AR®), grupo 2HE (10 implantes HE INP Teres®) e grupo 2HI (10 implantes HI INP®), grupo 3HE (10 implantes HE Titamax®) e grupo 3HI (10 implantes HI Titamax II®), e grupo 4HE (10 implantes HE Serson®) e grupo 4 HI (10 implantes HI Serson Implus®). A análise microbiológica foi realizada após a incubação da espécie Streptococcus sanguis na parte interna do implante. Os implantes foram removidos das embalagens e manipulados com pinças estéreis ao redor do bico de Bunsen, de maneira que não perdessem as características de fabricação ou sofressem qualquer tipo de contaminação externa. Em seguida foi realizada a adaptação de um conector protético parafusado manualmente a um torque que variou de 20 a 30 Ncm de acordo com as recomendações dos fabricantes. A composição foi inserida em um meio de cultura BHI (Brain Heart Infusion) armazenada em uma estufa bacteriológica por um período de 30 dias até que ocorresse ou não contaminação externa do meio BHI. Leituras diárias para verificação da contaminação foram realizadas nesse período. Após os 30 dias todos os implantes foram submetidos a uma análise em microscopia eletrônica de varredura para a verificação das dimensões dos microespaços na interface implante/conector protético, com aumento variando de 25 vezes até 2500 vezes. Observou-se uma grande diferença no grau de contaminação bacteriana entre as marcas de implantes variando de 0 % para os implantes Titamax II® (Neodent - hexágono interno) e Serson® (Serson - hexágono externo), até 90% para os implantes Teres® (INP - hexágono externo), apresentando diferenças estatísticas significativas. Porém, considerando-se apenas os tipos de hexágono, de um modo geral, pode-se verificar que não houve diferença estatisticamente significante, no grau de contaminação bacteriana entre os implantes de hexágono externo e interno. Sendo que a média do microespaço na interface implante/conector protético, encontrada na análise de microscopia eletrônica de varredura não apresentou correlação com o grau de contaminação bacteriana / Abstract: The purpose of this study was to evaluate in vitro the bacterial contamination through the implant/ prosthetic connector interface of four commercial brands of commercially pure titanium endosseous implants, and correlate it with the microgap dimensions in this interface. All implant systems are nationally manufactured. Eighty two-stage implants and their respective prosthetic connectors (40 external hexagon - HE and 40 internal hexagon - HI) were divided into 8 groups of 10 implants each, according to the commercial brands and hexagon type. Group 1HE (10 implants HE Master Screw®), group 1HI (10 implants HI Master Conect AR®), group 2HE (10 implants HE INP Teres®), group 2HI (10 implants HI INP®), group 3HE (10 implants HE Titamax®), group 3HI (10 implants HI Titamax II®), group 4HE (10 implants HE Serson®) and group 4HI (10 implants HI Serson Implus®). The microbiological analysis was performed by incubation of Streptococcus sanguis in the internal part of the implants. The implants were removed from their packages and manipulated with sterile tweezers near a Bunsen burner, to prevent contamination or loss of their characteristics. A prosthetic connector was then adapted manually with a 20 to 30 Ncm torque, according to the manufacturers¿ recommendations. The composition was inserted in a Brain Heart Infusion (BHI) culture medium, and stored in a bacteriological stove for a period of 30 days, until the external contamination of the BHI medium could be assessed. Daily evaluations to verify the contamination were performed in this period. After 30 days, all implants were subjected to a scanning electron microscopic (SEM) analysis to assess the dimension of the microgaps in the implant/ prosthetic connector interface, under a 25 to 2500x magnification. Different contamination degrees of the groups could be observed, varying from zero% in brands Titamax II® (Neodent - internal hexagon) and Serson® (Serson - hexagon external), to 90% in the implants Teres® (INP - hexagon external), with statistically significant differences. However, when all HE and all HI implants were compared, there was no significant difference in the contamination degrees between external and internal hexagon implants. The mean microgap in the implant/ prosthetic connector interface, found in the SEM, did not present a correlation with the bacterial contamination degrees / Mestrado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Mestre em Clínica Odontológica
9

Analise dos efeitos da interação entre S mutans e materiais restauradores esteticos : caracteristicas do biofilme em microscopio confocal de varredura a laser e propriedades de superficie dos materiais apos 30 dias / Analysis of the interaction between S. mutans and esthetic restorative materials : biofilm chracteristics by confocal laser scanning microscopy and material surface properties after 30 days

Fúcio, Suzana Beatriz Portugal de 02 July 2007 (has links)
Orientadores: Regina Maria Puppin Rontani, Renata de Oliveira Mattos-Graner / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-08T10:43:29Z (GMT). No. of bitstreams: 1 Fucio_SuzanaBeatrizPortugalde_M.pdf: 1914666 bytes, checksum: 2dbf8bdbcedb3127f232b29d0b441c5b (MD5) Previous issue date: 2007 / Resumo: O desenvolvimento do biofilme de Streptococcus mutans sobre materiais restauradores e a biodegradação destes substratos em função dos metabólitos bacterianos podem ser influenciados pelas propriedades e características do material. A partir de uma revisão sistemática em que se verificou a carrência de estudos a respeito dos efeitos do biofilme na superície de materiais restauradores, foi proposto investigar algumas características quantitativas e qualitativas do biofilme após 30 dias de interação com materiais restauradores, além de analisar propriedades e microestrutura da superfície dos materiais que sofreram tal interação. Para cada material testado (cerâmica - C, resina composta nanoparticulada e cimentos de inúmero de vidro modificado por resina - CIVMR e convencional - CIVC), foram confeccionados 25 discos sob condições assépticas, para distribuição em 3 grupos de estocagem: 1) 100% de umidade relativa a 37ºC (n=5); 2) meio de cultura a 37ºC (BHI + 1% sacarose) (n=5); 3) biofilme de Streptococcus mutans e meio de cultura a 37ºC (n=15). Valores de dureza do grupo 1 (valores imediatos) foram obtidos previamente à estocagem, a fim de se verificar alterações ao longo do tempo quando estocados em umidade relativa apenas. Após 30 dias de estocagem, os discos do grupo 3 foram levados para observação do biofilme corado e hidratado em microscopia de varredura confocal a laser (CLSM). As imagens obtidas auxiliaram na obtenção de valores / Abstract: Streptococcus mutans biofilm development on restorative materials and biodegradation of those materials due to bacterial acids are influenced by material properties and characteristics. Since a systematic review found a deficiency concerning studies related to effects of biofilm on the surface of restorative materials, the proposition for this investigation was to analyze some quantitative and qualitative biofilm characteristics after 30-days interaction with restorative materials. In addition, it was investigated changes on the surface properties and microstructure of materials after 30-days interaction. Twenty-five disks of each material tested (ceramic - C, nanofill composite - NC, resin-modified glass ionomer - RMGIC and conventional glass ionomer cement - CGIC) were made, at aseptic conditions, and distributed in 3 storage groups: 1) 100% relative humidity at 37ºC (n=5); 2) growth medium at 37ºC (BHI + 1% sucrose) (n=5); 3) Streptococcus mutans biofilm and growth medium at 37ºC (n=15). Vickers hardness values from group 1 were obtained previously storage, in order to observe aging by relative humidity. After 30 days storage, disks were stained, kept hydrated and observed by confocal laser scanning microscopy, whose images supported to acquire values concerning biofilm thickness, bio-volume, roughness coefficient and surface to volume ratio. Qualitative analyses related to viable / non-viable cells distribution and biofilm architecture also were realized. Subsequently, all disks were ultrasonically washed and analyzed to surface roughness, hardness and microstructure. Biofilms presented a progression more viable cells in superficial regions of the biofilm to proportionally more nonviable cells in the deeper regions of the biofilms, near the disk. Besides, cellular aggregates and fluid-filled channels were observed in biofilm developed on all materials. Concerning biofilm quantitative properties, thickness was the unique with difference statistically significant among materials. C and NC accumulated thicker biofilms than RMGIC and CGIC. There was no difference statistically significant among immediate and storage groups related to C and NC surface roughness and hardness. However, group 3 of NC showed surface biodegradation microscopically. Group 1 of RMGIC and CGIC presented higher hardness values than immediate values. Nevertheless, hardness values from RMGIC group 3 decreased compared groups 1 and 2, while surface roughness values of group 3 increased statistically. Group 3 of CGIC showed higher roughness values than other groups and no difference statistically significant among three storage groups concerning hardness values. RMGIC and CGIC micrographs also demonstrated biodegradation on the surface materials. Within this study conditions, it was concluded that there was influence of restorative materials on biofilm development and influence of biofilm on the surface properties and microstructure characteristics of materials tested, being material -dependent / Mestrado / Materiais Dentarios / Doutor em Materiais Dentários
10

Efeito das tecnologias alternativas para preparo cavitario nos procedimentos adesivos com sistemas autocondicionates

Oliveira, Marcelo Tavares de 25 February 2005 (has links)
Orientadores: Marcelo Giannini, Simonides Consani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-04T03:24:00Z (GMT). No. of bitstreams: 1 Oliveira_MarceloTavaresde_M.pdf: 5082541 bytes, checksum: c0624f8aeb1f1de12e33ab3c2ce83f13 (MD5) Previous issue date: 2005 / Resumo: O objetivo deste estudo foi avaliar o efeito de técnicas de preparo cavitário nos procedimentos adesivos com sistemas autocondicionantes. Foram analisadas as resistências à tração da união após os tratamentos, assim como, em microscopia eletrônica de varredura (MEV), as características morfológicas das estruturas formadas na região da união dentina-compósito; a morfologia da superfície produzida pelos tratamentos utilizados para preparar a dentina e o padrão de fratura dos espécimes testados no ensaio de microtração. Foram utilizados 208 terceiros molares humanos, que tiveram a superfície oclusal removida para a exposição de dentina de profundidade superficial e foram divididos aleatoriamente em 32 grupos experimentais. As tecnologias de preparo cavitário foram: ausência de smear layer, abrasionamento com lixas de SiC 600, ponta diamantada (100µm),broca carboneto de tungstênio (10 lâminas), aplicação de jato de óxido de alumínio 271µm,aplicação de laser Er:YAG, ponta diamantada CVD em ultra-som e Carisolv®.Após o tratamento superficial foi aplicado um dos sistemas adesivos de acordo com as instruções dos fabricantes (Tyrian, Clearfil SE Bond, Unifil Bond e Single Bond), em seguida restaurados com o compósito Clearfil AP-X. Os dentes foram armazenados em água destilada a 3rC durante 24 horas. Após esse período, os dentes foram seccionados perpedicularmente a interface de união, nos sentidos mésio-distal e vestíbulo-lingual, com a finalidade de se obter palitos com área de secção transversal de 0,7mm2. Os espécimes foram testados com o ensaio de microtração numa velocidade de 0,5mm/min até a ruptura. Os resultados foram analisados com ANOVA dois-critérios e teste Tukey. Foi identificada uma interação entre os tratamentos e os sistemas adesivos (p<0,00003).O tratamento com o laser de Er:YAG na condição do experimento e a ponta diamantada CVD em ultra-som apresentaram os piores resultados para todos os sistemas. O Carisolv® apresentou valores de resistência de união intermediários, porém os adesivos autocondicionantes mostraram resultados inferiores ao Single Bond. A ponta diamantada, a broca carboneto de tungstênio e a lixa de SiC 600 mostraram os resultados semelhantes. A abrasão a ar proporcionou maiores valores de resistência de união para o Clearfil SE Bond que apresentou resultado superior ao Tyrian. Os sistemas Clearfil SE Bond e Single Bond foram superiores, obtendo os maiores valores na ausência de smear layer, no entanto, o Unifil Bond foi semelhante ao Single Bond. As análises em MEV revelaram variações na formação da camada híbrida e uma predominância do padrão de fratura com falha adesiva entre o sistema de união e a dentina, e parcialmente coesiva no sistema de união. Foi observado que existe uma forte dependência entre as tecnologias utilizadas para a realização dos preparos cavitários e os sistemas de união, porém a técnica do condicionamento com ácido fosfórico pode reduzir o efeito das tecnologias sobre a resistência de união, exceto pela aplicação do laser de Er:YAG e da ponta diamantada CVD em ultra-som / Abstract: The aim of this study was to evaluate the effect of alternative cavity preparation techniques on the adhesive procedures with self-etching adhesive systems. Microtensile bond strength tests (µTBS), as well as, analysis under scanning electron microscope (SEM) of the morphological characteristics of the bonded structures, treated dentin surfaces and the failure mode of the tested specimens were performed. 208 third human molars had their oclusal surface flattened in order to expose superficial dentin. Teeth were randomly assigned to 32 experimental groups. Cavity preparation techniques used in this study were: smear layer free surface, 600-grit SiC paper, diamond bur (100µm,)carbide bur (10 blades), air abrasion, Er:YAG laser, CVD diamond bur - sonoabrasion and Carisolv® gel. Following each surface treatment, adhesive systems (Tyrian, Clearfil SE Bond, Unifil Bond and Single Bond) were applied according to manufacturer's instructions and 6mm high blocks were incrementally built up with Clearfil AP-X (Kuraray) composite resin. The specimens were stored for 24 hours at 37°C in distilled water and were serially sectioned in both mesio-distal and buccal-lingual directions transversally to the bonded interface to obtain an array of bonded beams with a cross-sectional area of 0.7mm2. Beams were tested in tension (0.5mm/min - Instron 4411) and results were analyzed with two-way ANOVA and Tukey's test. It was found an interaction between adhesive systems and surface treatments (p<0.00003). Sonoabrasion and laser treatment yielded the lowest values for the tested adhesive systems; Carisolv® gel showed intermediate bond strength, however, self-etching adhesive systems were worse than Single Bond. Diamond bur, carbide bur and 600-grit SiC paper had similar results. Air-abrasion produced improved results for adhesion with Clearfil SE Bond that was significantly better than Tyrian. Clearfil SE Bond and Single Bond were superior, obtaining the highest values of The aim of this study was to evaluate the effect of alternative cavity preparation techniques on the adhesive procedures with self-etching adhesive systems. Microtensile bond strength tests (µTBS), as well as, analysis under scanning electron microscope (SEM) of the morphological characteristics of the bonded structures, treated dentin surfaces and the failure mode of the tested specimens were performed. 208 third human molars had their oclusal surface flattened in order to expose superficial dentin. Teeth were randomly assigned to 32 experimental groups. Cavity preparation techniques used in this study were: smear layer free surface, 600-grit SiC paper, diamond bur (100µm,)carbide bur (10 blades), air abrasion, Er:YAG laser, CVD diamond bur - sonoabrasion and Carisolv®gel. Following each surface treatment, adhesive systems (Tyrian, Clearfil SE Bond, Unifil Bond and Single Bond) were applied according to manufacturer's instructions and 6mm high blocks were incrementally built up with Clearfil AP-X (Kuraray) composite resin. The specimens were stored for 24 hours at 37°C in distilled water and were serially sectioned in both mesio-distal and buccal-lingual directions transversally to the bonded interface to obtain an array of bonded beams with a cross-sectional area of O.7mm2. Beams were tested in tension (0.5mm/min - Instron 4411) and results were analyzed with two-way ANOVA and Tukey's test. It was found an interaction between adhesive systems and surface treatments (p<0.00003). Sonoabrasion and laser treatment yielded the lowest values for the tested adhesive systems; Carisolv® gel showed intermediate bond strength, however, self-etching adhesive systems were worse than Single Bond. Diamond bur, carbide bur and 600-grit SiC paper had similar results. Air-abrasion produced improved results for adhesion with Clearfil SE Bond that was significantly better than Tyrian. Clearfil SE Bond and Single Bond were superior, obtaining the highest values of µTBS for the smear layer free surface, although in the comparison among the adhesive systems Unifil Bond and Single Bond were similar. SEM analysis revealed some variations in the hybrid layer formation and the predominance of an adhesive failure between adhesive system and dentin, and partially cohesive in the adhesive system. It was also observed that there is a strong relationship between cavity preparation techniques and adhesive systems, however, the total-etch technique seems to levei the effect over the µTBS, except for the Er:YAG laser treatment and sonoabrasion / Mestrado / Dentística / Mestre em Clínica Odontológica

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