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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.
11

Characterization of the incipient stages of dental integuments with respect to proteins and microorganisms

Heller, Debora 03 November 2016 (has links)
It is well established that biofilm formed on tooth surfaces is the major culprit for caries and periodontal disease development. The critical early event of biofilm formation is the specific interaction of microorganisms with the acquired enamel pellicle. This pellicle is formed from adsorbing proteins from saliva, and perhaps also from gingival crevicular fluid. The purpose of this project was two fold: first, to investigate the extent of serum protein adsorption in a salivary protein environment, and second, to investigate the colonization of salivary pellicles by early microbial colonizers. Hydroxyapatite (HA) was incubated with saliva and serum and adsorbing proteins were identified by LC-ESI-MS/MS. To investigate competition among salivary and serum proteins for adsorption to HA proteins were labeled with specific CyDyes, mixed in various ratios and incubated with HA. The early phase of oral biofilm formation in vivo was studied on teeth exposed to the oral environment. The harvested biofilm samples were analyzed with the Human Oral Microbiome Identification Microarray containing 407 different microbial probes. In the pure saliva- and serum-derived pellicles eighty-two and eighty-four proteins were identified. Concomitant presence of salivary and serum proteins showed that salivary protein adsorbers effectively competed with serum proteins adsorbers for the HA surface. Specifically acidic proline-rich protein, cystatin, statherin and amylase proteins in saliva competed off apolipoprotein, C-reactive protein, peroxiredoxin-1 and albumin. In vivo evidence supported the replacement of serum proteins by salivary proteins. The studies with oral biofilm formed in vivo led to the identification of 92 species with streptococci being the most abundant early colonizers. High frequency detection was furthermore made with Haemophilus parainfluenzae, Gemella haemolysans, Slackia exigua and Rothia species. Eight uncultivated phylotypes were detected. While there is a significant amount of serum protein emanating from the gingival sulcus, their ability to participate in dental pellicle formation is likely reduced in the presence of strong salivary protein adsorbers. Furthermore, the early pellicle colonizers exhibit considerable bacterial diversity and include non-cultivable species. These findings will be helpful in designing target-specific approaches for the prevention of and/or intervention in diseases exhibiting an oral-biofilm-based etiology.
12

Perfil imunológico e microbiológico de pacientes com periodontites crônica e agressiva / Immunological and microbiological profiles of chronic and agressive periodontitis subjects

Bruno Rescala Conde de Medeiros 29 March 2010 (has links)
O objetivo deste estudo foi determinar os níveis de interleucina-1&#946; (IL-1 &#946;), IL-2, IL-4, IL-8, interferon-&#947; (IFN-&#947;) e a atividade de elastase no fluido gengival (FG) de pacientes com periodontite crônica generalizada (PCG) e periodontite agressiva generalizada (PAgG), e correlacionar com indivíduos de um grupo controle com gengivite apenas. Um objetivo secundário foi analisar o perfil microbiológico subgengival destes indivíduos. Dados clínicos transversais foram obtidos de 20 pacientes com PCG, 17 pacientes com PAgG e 10 indivíduos com gengivite. Amostras de FG foram coletadas com tiras de papel e os níveis de: IL-1&#946;, IL-2, IL-4, IL-8 e IFN-&#947; foram medidos, utilizando um imunoensaio do tipo multiplex (Luminex). Atividade da elastase foi avaliada por um ensaio enzimático. Amostras de placa subgengival foram analisadas através do checkerboard DNA-DNA hybridization. As diferenças de significância entre os grupos para dados imunológicos e microbiológicos foram realizadas utilizando o teste Kruskal-Wallis, ajustando para múltiplas comparações. As médias dos parâmetros clínicos e os volumes de FG foram maiores nos pacientes com PCG e PAgG comparados ao grupo gengivite. Níveis mais elevados de IL-1&#946; e atividade de elastase foram encontrados em sítios profundos quando comparado a sítios rasos em ambos os grupos com periodontite (p <0,05). Os dados microbiológicos apresentaram níveis significativamente mais elevados das espécies do complexo vermelho em pacientes com PCG e PAgG, quando comparados aos indivíduos com gengivite (p <0,05). Não houve diferença estatisticamente significante nos níveis de biomarcadores no FG e nos níveis de espécies bacterianas subgengivais entre pacientes com PCG e pacientes com PAgG. Sendo assim, concluímos que os dados do presente estudo não mostraram diferença estatisticamente significante nos parâmetros imunológicos e microbiológicos medidos entre indivíduos com PCG e PAgG. / The goal of this study was to determine the gingival crevicular fluid (GCF) levels of interleukin-1&#946; (IL-1&#946;), IL-2, IL-4, IL-8 and interferon-&#947; (IFN-&#947;) and elastase activity from patients with generalized chronic (GCP) and generalized aggressive periodontitis (GAgP) and to compare with a control group with gingivitis subjects. A secondary aim was to analyze the microbiological profile of these subjects. Cross-sectional clinical data were obtained from 20 GCP, 17 GAgP and 10 gingivitis subjects. GCF samples were collected with paper strips and the levels of: IL-1&#946;, IL-2, IL-4, IL-8, and IFN-&#947; measured using a multiplexed bead immunoassay (Luminex). Elastase activity was assessed by an enzymatic assay. Subgingival plaque samples were analyzed using checkerboard DNA-DNA hybridization. Significance of differences among groups for immunological and microbiological data was examined using Kruskal-Wallis adjusting for multiple comparisons. Mean clinical parameters and GCF volumes were higher in GCP and GAgP patients compared to controls. Higher levels of IL-1&#946; and higher elastase activity were found in deep sites compared to shallow sites in both periodontitis groups (p<0.05). The microbiological data showed significantly higher levels of the Red complex species in GCP and GAgP patients compared to controls (p<0.05). There were no statistically significant differences in levels of GCF biomarkers and in levels of subgingival bacterial species between GCP and GAgP subjects. In conclusion, there were no statistically significant differences in the measured immunological and microbiological parameters between GCP and GAgP subjects.
13

Alteração do volume de fluido gengival de pacientes com periodontite crônica em manutenção periodontal sob tratamento ortodôntico: estudo piloto / Change in the amount of gingival crevicular fluid of patients with chronic periodontitis in periodontal maintenance under orthodontic treatment: a pilot study

Rivail Antonio Sergio Fedel Junior 26 February 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo do estudo foi mensurar as alterações na quantidade do volume de fluido gengival (FG) dos dentes submetidos à movimentação ortodôntica, em adultos com periodontite crônica na fase de manutenção periodontal. O FG foi coletado com uma tira de papel absorvente padrão das áreas de pressão dos dentes de 10 pacientes (sete homens e três mulheres) e medido em microlitro no Periotron em seis dias distintos (dia -7, dia 0, dia 1, dia 7, dia 14 e dia 21). Os pacientes foram submetidos a um rigoroso programa de controle de placa. O teste de Wilcoxon foi aplicado para comparar os dados obtidos. Os resultados mostraram que o controle de placa efetivo baixou a quantidade de FG do dia -7 para o dia 0, e em seguida houve uma elevação do FG até o dia 7 por conta do início da movimentação ortodôntica, e uma nova queda do dia 7 até o 21. O maior volume de FG foi encontrado no dia 7, uma semana após o início da movimentação. O menor volume no dia 0. Concluindo, a movimentação ortodôntica aumentou o volume de FG do dia 0 até o dia 7. / The aim of this study was to measure the alterations in the amount of gingival crevicular fluid (GCF) of teeth during orthodontic tooth movement in adults with chronic periodontitis under a periodontal maintenance program. The GCF was collected with paper stripes from pression sides of teeth in 10 patients (7 males and 3 females) and measured in microlitres on Periotron in six distinct periods of time (day -7, day 0, day 1, day 7, day 14, day 21). Patients were under supervised program of plaque control. Wilcoxon test was applied to compare the data. The results shown that the effective plaque control reduces the amount of GCF from day -7 to day 0, followed by an elevation until day 7 after the beginning of orthodontic tooth movement and a new reduce from day 7 to 21. The highest amount of GCF was found on day 7, one week after the beginning of tooth movement, while the smallest found on day 0.
14

Nitric Oxide Changes in Gingival Crevicular Fluid Following Orthodontic Force Application

Ford, Heather Nicole 22 November 2013 (has links)
Nitric oxide (NO) plays a role in regulating the rate of orthodontic tooth movement (OTM) in rat models; however, in humans this role remains less clear. In this study, samples of gingival crevicular fluid (GCF) were collected from each maxillary central incisor and first and second molar immediately before (T0), 1 hour after (T1), and 3-4 days after (T2) application of light orthodontic forces in thirteen male participants (ages 11-18 years) undergoing orthodontic therapy. NO levels were measured in each GCF sample, and significantly higher NO levels (p<0.05) were found at T1 at the buccal surfaces of the central incisors when compared to the posterior teeth. The results indicate a possible role for NO in OTM at the pressure sites of incisors at early time points. Further studies are required to determine whether NO levels in the PDL of human teeth are affected by the magnitude of an applied force.
15

Nitric Oxide Changes in Gingival Crevicular Fluid Following Orthodontic Force Application

Ford, Heather Nicole 22 November 2013 (has links)
Nitric oxide (NO) plays a role in regulating the rate of orthodontic tooth movement (OTM) in rat models; however, in humans this role remains less clear. In this study, samples of gingival crevicular fluid (GCF) were collected from each maxillary central incisor and first and second molar immediately before (T0), 1 hour after (T1), and 3-4 days after (T2) application of light orthodontic forces in thirteen male participants (ages 11-18 years) undergoing orthodontic therapy. NO levels were measured in each GCF sample, and significantly higher NO levels (p<0.05) were found at T1 at the buccal surfaces of the central incisors when compared to the posterior teeth. The results indicate a possible role for NO in OTM at the pressure sites of incisors at early time points. Further studies are required to determine whether NO levels in the PDL of human teeth are affected by the magnitude of an applied force.
16

The effect of waxed and unwaxed dental floss on crevicular fluid flow and gingival bleeding a thesis submitted in partial fulfillment ... periodontics ... /

Wunderlich, Richard C. January 1980 (has links)
Thesis (M.S.)--University of Michigan, 1980.
17

The effect of waxed and unwaxed dental floss on crevicular fluid flow and gingival bleeding a thesis submitted in partial fulfillment ... periodontics ... /

Wunderlich, Richard C. January 1980 (has links)
Thesis (M.S.)--University of Michigan, 1980.
18

Changes in the composition of gingival crevicular fluid after periodontal treatment

Talonpoika, Juha. January 1994 (has links)
Thesis--University of Turku, 1994. / Added t.p. with thesis statement inserted. Includes bibliographical references.
19

Changes in the composition of gingival crevicular fluid after periodontal treatment

Talonpoika, Juha. January 1994 (has links)
Thesis--University of Turku, 1994. / Added t.p. with thesis statement inserted. Includes bibliographical references.
20

Efeito do movimento dentário nos níveis de metaloproteinases da matriz no fluido gengival de pacientes com periodontite controlada / Levels of GCF matrix metalloproteinases in periodontally compromised teeth under orthodontic forces

Rhita Cristina Cunha Almeida 26 June 2012 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O objetivo deste trabalho foi examinar o impacto da movimentação dentária de dentes periodontalmente comprometidos no volume do fluido gengival crevicular (FGC) e nos níveis de expressão das metaloproteinases de matriz (MMPs) -1, -2, -3, -7, -8, -12 e -13 no FGC. Dez pacientes periodontalmente controlados (8 do sexo feminino e 2 do sexo masculino, média de idade de 46,2 10,4 anos) com incisivos projetados labialmente foram submetidos a tratamento ortodôntico. Uma arcada dentária foi submetida a movimentação ortodôntica e a arcada oposta foi usada como controle. Amostras de FGC foram coletadas da face lingual de dois incisivos do lado movimento e dois do lado controle uma semana antes da ativação ortodôntica (-7d), imediatamente após a ativação ortodôntica, e após 1 h, 24 h, e 7, 14 e 21 dias. A coleta do FGC foi feita utilizando-se tiras de papel absorvente e o volume foi calculado através do uso do Periotron. Todos os pacientes receberam orientações de higiene bucal e um kit contendo escova de dente, pasta de dente e bochecho de Chlorexidina 0,12% para ser usado durante todo o experimento. A técnica da multianálise imunoenzimática com microesferas foi usada para medir as MMPs no FGC. Os dados foram analisados utilizando-se os testes estatísticos Friedman e Mann-Whitney. Não foram encontradas diferenças estatisticamente significativas no volume do FGC. Em relação aos níveis de MMPs, a única diferença estatisticamente significativa encontrada no decorrer do tempo foi nos níveis de MMP-1 no grupo movimento (p<0,05). Quando os dois grupos foram comparados após a ativação, a única diferença estatisticamente significativa encontrada foi nos níveis de MMP-12 24 horas após a ativação (p<0,05). Estes achados sugerem que o volume de FGC não sofre alteração relacionada ao movimento dentário ortodôntico e que o movimento ortodôntico de dentes periodontalmente comprometidos não resultou em mudanças significativas nos níveis de MMPs no FGC. / The aim of this study was to evaluate whether orthodontic tooth movement of periodontally compromised teeth would result in detectable changes in gingival crevicular fluid (GCF) volume and in the levels of matrix metalloproteinases (MMP) -1, -2, -3, -7, -8, -12 and -13 in the GCF. Ten controlled periodontitis subjects (8 females and 2 males, mean age of 46.2 10.4 years) with flared incisors were submitted to orthodontic treatment. One dental arch was subjected to orthodontic movement, and teeth in the opposite arch were used as controls. GCF samples were collected from the lingual sites of two test and two control incisors one week before orthodontic activation (-7d), immediately after orthodontic activation, and after 1 h, 24 h, and 7, 14 and 21 days. Filter paper strips were used in combination with a Periotron for GCF volume measurements. All patients received hygiene instructions and a kit containing toothbrush, fluoride dentifrice and gluconate chlorexidine 0.12% mouthwash to be used during all experiment. Multiplexed bead immunoassay was used to measure MMPs in GCF. Data were analyzed using Friedman and Mann-Whitney statistical tests. There were no statistically significant differences over time in the GCF volume for any of the two groups. Regarding the MMPs levels, the only significant change found over time was in the levels of MMP-1 in the movement group (p<0.05). When the two groups were compared after activation, the only statistically significant difference found was in levels of MMP-12 24 h after activation (p<0.05). This findings suggested that the GCF volume could not be associated to orthodontic movement and that the orthodontic movement of periodontally compromised teeth did not result in significant changes in the GCF levels of MMPs.

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