No description available.

No description available.

A qualidade de uma reconstrução protética depende, primordialmente, de sua integração biológica e da sua adaptação. O afastamento gengival serve para se obter espaço para o material de moldagem e também para a visualização e acesso aos limites gengivais dos preparos, que são essenciais para a confecção de próteses com uma justeza de adaptação clínica. No entanto, a inserção de um material (fio retrator ou casquete) pode romper o sistema de fibras gengivais que conectam a margem gengival à superfície do cemento causando recessão gengival. Ocasionalmente, ocorre significativa inflamação ou perda de inserção. O objetivo deste trabalho foi quantificar a resposta inflamatória decorrente das diferentes técnicas de moldagem para prótese fixa, em termos da quantidade de IL-2, IL-4, IL-5, IL-10, TNF-α, IFN-γ, presentes no fluido gengival dos dentes com necessidade protética. A amostra foi composta por 10 dentes moldados pela técnica de afastamento gengival com fio retrator e um grupo de 10 dentes moldados pela técnica do casquete. Os pacientes foram selecionados considerando-se a necessidade de prótese parcial fixa, higiene bucal satisfatória e não possuírem sinais clínicos de doença periodontal. Previamente à moldagem, uma tira de periopaper foi inserida no sulco gengival do paciente e foi mantida por 30 segundos. A coleta foi repetida 4 vezes para as faces mesiovestibular, distovestibular, mesiolingual e distolingual. Terminado o procedimento da moldagem, após 2 horas, 4 horas e 24 horas, respectivamente, foi repetido o procedimento de inserção do periopaper nos 4 sítios dos dentes. A amostra foi preparada para a citometria de fluxo (CBA - cytometric beads array). Os resultados foram analisados pelo teste de Tukey. Na análise de variância a 3 critérios, por meio da comparação entre técnica de moldagem, paciente e tempo para os valores de TNF-α, a relação tempo e paciente versus tempo foi estatisticamente significante (p?0,05). Na comparação entre a técnica de moldagem com casquete e o fio retrator, não houve superioridade entre uma técnica e outra(p?0,05). O teste Tukey para a comparação intragrupo tempo (4 tempos), independente de técnica e paciente, mostrou relevância estatística entre os períodos antes da moldagem e após 24 horas (p=0,016) e, no período entre 2 horas e 24 horas após a moldagem (p=0,06). Portanto, foi possível concluir que não existe evidência científica que demonstre alguma superioridade das técnicas estudadas. Com isso, a escolha pelo método de afastamento gengival depende da situação clínica e habilidade do profissional. / The quality of a prosthetic reconstruction depends mostly on its integration and its biological adaptation. The gingival retraction serves to provide space for the impression material and also for visualize and give access to the gingival limit of tooth preparations, which are essential for making prostheses with a reliable clinical precision fit. However, the inclusion of a material (retractor cord or acrilic resin coping) can break the system of gingival fibers that connect the gingival margin to cementum´s surface, causing gingival recession. Occasionally, inflammation or significant insertion loss occurs. The aim of this study was to quantify the inflammatory response resulting from differents impression techniques for fixed prosthodontics in terms of the quantity of IL-2, IL-4, IL-5, IL-10, TNF-α, IFN-γ, found in gingival fluid of tooths needing prosthetic restorations. The sample consisted of 10 teeth impressed by gingival retraction cord technique and a group of 10 teeth using acrilic resin coping technique. Patients were selected considering the need for fixed partial denture, good oral hygiene and absence of periodontal disease´s clinical signs. Prior taking impressions, a Periopaper strip was inserted into the gingival sulcus of patients and was maintained for 30 seconds. The collect was repeated 4 times to the mesiobuccal, distovestibular, mesiolingual and distolingual sides: After the impression procedure, collecting was repeated after 2 hours, 4 hours and 24 hours respectively. the Periopaper strip was inserted on the teeth´s four sites. The sample was prepared for flow cytometry examination (CBA - cytometric beads array). The results were evalueted by Tukey test. The 3-way analysis of variance criteria,comparing impression technique, patient and time to values of TNF-α, the relationship between time and patient versus time was statistically significant (p ? 0.05). Comparing the acrilic resin coping and retraction cord impression techniques, there was no superiority between each other (p ? 0.05). The Tukey test for intragroup comparison time (4 times) irrespective of technique and patient showed statistical significance between periods before the impression and after 24 hours (p=0,016) and the period between 2 and 24 hours after impressions (p=0,06). Therefore, it was concluded that there is no scientific evidence that exists any superiority between the techniques studied. Thus, the choice of gingival retraction method depends on the clinical situation and professional´s skills.

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.

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.

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.

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.

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.

Thesis (M.S.)--University of Michigan, 1980.

Thesis (M.S.)--University of Michigan, 1980.