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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.
81

"Análise da citotoxicidade do EDTA e do ácido cítrico aplicados em cultura de macrófagos peritoneais residentes" / Cytotoxicity analysis of EDTA and citric acid applied on murine resident macrophages culture.

Kali Fatima Amaral 08 December 2004 (has links)
O presente estudo avaliou in vitro o efeito citotóxico das soluções de EDTA a 17% e ácido cítrico a 15% sob macrófagos peritoneais residentes, valendo-se do método MTT. Após anestesia e sacrifício de 32 camundongos Swiss machos, procedeu-se a coleta do exsudato celular pela injeção e aspiração de meio de cultura estéril na cavidade abdominal dos animais. Pelo processamento do exsudato peritoneal, obteve-se em média 95% de macrófagos. Alíquotas de 5 x 10 5 células foram plaqueadas em triplicata, de acordo com os grupos experimentais. Diluições de 0,5% de EDTA e ácido cítrico foram adicionadas ao meio de cultura num total de 1 mL. O grupo controle recebeu somente meio de cultura estéril. Verificou-se a citotoxicidade em dois momentos: períodos de curto prazo (0, 6, 12 e 24 horas) e médio prazo (1,3, 5, 7 dias). Ao final dos referidos tempos de observação, as amostras foram tratadas pelo corante MTT, obtendo-se valores de absorbância em leitora ELISA 550 nm. Todo o procedimento experimental foi repetido 2 vezes. No período de curto prazo, a análise de variância apontou diferenças significantes (p< 0,05), sendo Fc=46,07 contra Ft= 3,15, para os grupos avaliados: os Grupos EDTA (0,253 nm) e ácido cítrico (0,260 nm) foram mais citotóxicos que o Grupo controle (0,355 nm). Observações de médio prazo revelaram significância estatística (p< 0,05) entre os grupos, sendo Fc= 171,0 contra Ft= 3,15. Ambas as soluções, EDTA (0,158 nm) e ácido cítrico (0,219 nm), mostraram maior toxicidade em relação ao controle (0,310nm), porém o EDTA apresentou-se mais citotóxico que o ácido cítrico, reduzindo substancialmente a população macrofágica. Como conclusão, as soluções irrigantes testadas exerceram toxicidade aos macrófagos peritoneais em cultura, no entanto, a viabilidade tardia destas células foi menos alterada pelo ácido cítrico / The present study evaluated in vitro cytotoxic effects of 17% EDTA and 15% citric acid in murine resident macrophages using MTT assay. After anesthesia and sacrifice of thirty two Swiss male mice, it had processed the peritoneal cellular exudates by fresh culture medium injection and aspiration in peritoneal animals cavities. The peritoneal exudates were composed approximately by 95% of macrophages. 5x 10 5 cells were plated in triplicate, according experimental groups. Each 0.5% dilutions of EDTA and citric acid were applied in medium culture, resulting 1 mL volume. Fresh medium served as control. The cytotoxicity was evaluated in two moments: short term (0, 6, 12, 24 hours) and long term (1, 3, 5, 7 days). After tested periods, the samples were treated by MTT ink assay and absorbance was determined using ELISA microplate reader at 550 nm. All these procedures were repeated twice. To short term period, ANOVA showed significant differences (p< 0.05) among groups (Fc= 46.07 x Ft= 3.15). EDTA (0.253 nm) and citric acid (0.260 nm) groups exhibited more cytotoxicity than control group. Long term observations exhibited statistical differences (p< 0.05), that Fc= 171.0 x Ft= 3.15. EDTA (0.158 nm) and citric acid (0.219 nm) solutions were cytotoxic when compared to control group, thus EDTA reduced greater macrophages viability than citric acid. Based on our results it seems that final irrigants tested presented toxic effects to murine macrophages culture, but in long term evaluation citric acid was considered less irritant.
82

Avaliação inflatória da associação da clorexidina com o hipoclorito de sódio em tecido conjuntivo de rato / Evaluation of inflammatory chlorhexidine with sodium hypochlorite irrigants in rat connective tissue

Guilherme Henrique Rosa Martins 24 September 2013 (has links)
A associação dos irrigantes endodônticos hipoclorito de sódio e clorexidina forma um precipitado amarronzado e subprodutos que podem ser tóxicos aos tecidos periodontais apicais. O objetivo deste trabalho foi de avaliar qualitativamente e quantitativamente a resposta inflamatória destes irrigantes e suas associações em tecido conjuntivo no dorso do rato. Foram utilizados 24 ratos machos Wistar, 220 gr, cuja região dorsal foram confeccionadas quatro feridas cirúrgicas por punch de 08mm que receberam 20 mL dos irrigantes endodônticos, sendo divididos em: soro fisiológico, solução de digluconato de clorexidina a 2%, hipoclorito de sódio a 1% e a 2,5%, mistura de 10mL de hipoclorito de sódio a 1% mais 10mL de clorexidina a 2% e mistura de 10mL de hipoclorito de sódio a 2,5% mais 10mL de clorexidina a 2%. O experimento foi realizado em triplicata e os animais foram sacrificados nos tempos experimentais de 0 (imediato), 24h, 72h e 168h. Os fragmentos foram fixados e corados com hematoxilina e eosina para análise histomorfológica. Para a quantificação celular, cortes histológicos dos grupos de 24, 72 e 168h foram tratados para serem imunomarcados pelos anticorpos para linfócitos CD4 e CD8, e Anti pan-macrófago para marcação de macrófagos. Foram tomadas três fotografias num aumento de 400x de cada lâmina, para serem quantificadas através do software ImageJ. Os dados foram tabulados e submetidos ao teste estatístico ANOVA (dois critérios), com pós-teste de Bonferroni (=0,05), comparando os grupos em função dos marcadores, tempos experimentais e grupos testados. Os resultados obtidos na análise microscópica puderam identificar variações significativas entre os grupos estudados e o controle. Enquanto que no controle não foi verificado um grau de inflamação elevado, nos grupos testados foram observados destruição tecidual, aumento de número e tamanho de vasos, infiltrado inflamatório intenso, edema e início de epitelização até 168h. Na análise quantitativa, foi observado um pico celular em 72h para todos os marcadores (p<0,001). Todos os grupos testados apresentaram níveis celulares maiores que o grupo do soro fisiológico (p<0,001), exceto para o marcador de macrófagos (p>0,05). As associações das substâncias em comparação com as substâncias isoladas não apresentaram diferenças significantes (p>0,05), exceto em 72h no marcador CD4 e com hipoclorito de sódio a 2,5% (p<0,001). Estes resultados foram similares tanto para os grupos individuais bem como nas associações. Pode-se concluir, do ponto de vista biológico, que a associação entre o hipoclorito de sódio e a clorexidina mostraram resposta inflamatória semelhante as substâncias isoladas e que podem ser empregados na terapia endodôntica. / The association of endodontic irrigants sodium hypochlorite and chlorhexidine results in the formation of a brownish precipitate and its byproducts can be toxic to the periodontal tissue. The aim of this study was to evaluate qualitatively and quantitatively the inflammatory response of these drugs and their associations in the connective tissue on the back of the mouse. Four dorsal surgical wounds made by 08mm punch in twenty four male Wistar rats of 220 gr received 20 mL of each endodontic irrigants and were divided into grupos: saline solution, 2% chlorhexidine digluconate, 1% and 2,5% sodium hypochlorite, mixture of 10 ml of 1% sodium hypochlorite plus 10 ml of 2% chlorhexidine and mixture of 10 ml of 2,5% sodium hypochlorite plus 10 ml of 2% chlorhexidine. The test was performed in triplicate, the animals sacrificed at 0h (immediately), 24h, 72h and 168h and the fragments fixed, stained with hematoxylin and eosin for histomorphological analysis. To quantify cells, histological sections from 24, 72 and 168h groups were treated and immunostained by CD4, CD8 lymphocytes and Anti-pan macrophage antibodies. Three pictures were taken in a 400x magnification of each slide and quantified using the ImageJ software. Data was tabulated and submitted to ANOVA (two-way) with Bonferroni post-test (=0.05) comparing the markers, times and experimental groups. The results obtained in the microscopic analysis identified significant differences among the experimental and control groups. In control group there was not high degree of inflammation; in the experimental groups there were tissue destruction, number and size of vessels increased, intense inflammatory infiltration, edema and early epithelialization at 168h. In the quantitative analysis a peak of all cell markers was observed at 72h (p<0.001). All experimental groups showed higher cellular levels than the saline group (p<0.001) except for the macrophages marker groups (p>0.05). The associated or isolated use of the substances showed no significant differences (p> 0.05) except for 72h CD4 marker and with 2.5% sodium hypochlorite group (p<0.001). The results were similar for both individuals and associated groups. In conclusion the association between sodium hypochlorite and chlorhexidine showed inflammatory process similar to isolated substances and therefore it can be utilized in endodontic therapy.
83

Avaliação in vitro do controle microbiano e da neutralização de endotoxinas presentes em canais radiculares por nanopartículas de prata / Effectiveness of silver nanoparticles on microorganisms and endotoxins in root canals

Cláudia de Moura Carreira 20 January 2010 (has links)
O objetivo deste trabalho foi avaliar a capacidade da solução de nanopartículas de prata, utilizada como irrigante e medicação intracanal, em controlar os microrganismos e neutralizar endotoxinas no canal radicular. Para isso, foram utilizadas 48 raízes de dentes humanos padronizadas em 16 mm e com diâmetro apical correspondente a uma lima tipo Kerr no. 30. Os canais foram contaminados por 28 dias com E. coli e por 21 dias com E. faecalis e C. albicans. Os espécimes foram divididos em quatro grupos (n=12), de acordo com a substância utilizada (solução irrigadora e medicação intracanal): G1) solução salina e solução salina (grupo controle); G2) hipoclorito de sódio 1% associado ao creme Endo-PTC e hidróxido de cálcio - protocolo tradicional da FOUSP; G3) solução de nanopartículas de prata 50 ppm e hidróxido de cálcio associado à solução de nanopartículas de prata; e G4) solução de nanopartículas de prata 50 ppm e solução de nanopartículas de prata 50 ppm. Foram realizadas cinco coletas do conteúdo do canal radicular para avaliar a atividade antimicrobiana: coleta de confirmação, imediatamente após a instrumentação (1ª. coleta) e outra após sete dias (2ª. coleta); imediatamente após a remoção da medicação (3ª. coleta) e outra após sete dias (4ª. coleta). A neutralização da endotoxina foi avaliada apenas nas quatro últimas coletas. Os resultados obtidos foram submetidos a análise estatística (Kruskall-Wallis e Dunn). Todas as soluções irrigadoras promoveram redução significativa dos microrganismos após a instrumentação (1ª. coleta) (p<0,05). Após 7 dias houve aumento do número de microrganismos em todos os grupos, voltando ao número inicial nos grupos instrumentados com solução salina e hipoclorito de sódio. Entretanto, apesar de ter ocorrido recolonização dos microrganismos no canal radicular dos espécimes instrumentados com solução de nanopartículas de prata, manteve-se redução estatisticamente significantemente do número de UFC/mL quando comparada à coleta de confirmação (p<0,05), demonstrando efeito residual. A medicação de hidróxido de cálcio eliminou 100% dos microrganismos e manteve os resultados após 7 dias (4ª. coleta) no grupo 2. No grupo quatro houve recolonização de E. faecalis e C. albicans após 7 dias de incubação. O hidróxido de cálcio foi a única substância avaliada que promoveu redução significativa (p<0,05) das endotoxinas. Assim, pôde-se concluir que o hipoclorito de sódio e a solução de NP-Ag reduziram significativamente a microbiota do canal, no entanto somente com a associação ao hidróxido de cálcio houve eliminação dos microrganismos em profundidade nos túbulos dentinários e redução das endotoxinas presentes no canal radicular. / The objective of this study was to evaluate the antimicrobial effect and endotoxin detoxified of solution of silver nanoparticles used as irrigating and dressing in root canals. Forty-eigth single-root human teeth were used. All root canals sized 16 mm and were enlarged to a Kerr file number .30. Root canals were infected for 28 days with E. coli and for 21 days with E. faecalis and C. albicans. The specimens were divided into four groups (n=12), according to the substance used (irrigating solution and dressing): G1) saline and saline (control), G2) sodium hypochlorite 1% with Endo-PTC cream and calcium hydroxide; G3) solution of Ag-NP 50 ppm and calcium hydroxide with Ag-NP; and G4) solution of Ag-NP 50 ppm and solution of Ag-NP 50 ppm. Five samplings of root canal were accomplished to evaluate the antimicrobial activity: confirmation sample, immediately after instrumentation (1st. Sample), and other after 7 days (2 nd. Sample), immediately after dressing removed (3 rd. Sample) and other after 7 days (4 th. Sample). The endotoxina detoxified was evaluated only in the last four samples by Limulus assay. Results were analysed by Kruskal-Wallis and Dunn. All irrigation solutions caused significant reduction of microorganisms after instrumentation (1 st. Collection) (p <0.05). After 7 days there was increase of the number of bacteria in all groups, returning to the initial number of microorganisms in the groups prepared with saline and sodium hypochlorite, however, the recolonization of microorganisms in root canals of groups of solution silver nanoparticles was smaller than the number of confirmation sample (p <0.05), showing residual effect. The calcium hydroxide eliminated 100% of the microorganisms and the results remained after 7 days (4 th. Collection) for group 2. In group 4 there was recolonization of E. faecalis and C. albicans after 7 days. Calcium hydroxide was the only substance that measured a significant reduction of endotoxin (p <0.05). Thus, we concluded that the sodium hypochlorite and the NP-Ag significantly reduced the microorganisms of the root canal, but it is necessary the combination of calcium hydroxide to eliminated all microorganisms into dentinal tubules and detoxified endotoxins in the root canal.
84

Influência da terapia endodôntica e do envelhecimento artificial acelerado na resistência de união de pinos de fibra de vidro à dentina intrarradicular / Influence of endodontic therapy and artificial accelerated aging on fibreglass post bond strength to intraradicular dentine

Santana, Fernanda Ribeiro 28 May 2012 (has links)
Submitted by Luanna Matias (lua_matias@yahoo.com.br) on 2015-03-09T11:19:12Z No. of bitstreams: 2 Tese - Fernanda Ribeiro Santana - 2012.pdf: 12111889 bytes, checksum: 84cf2d3d0d514483cc202fde5fa79301 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luanna Matias (lua_matias@yahoo.com.br) on 2015-03-09T14:09:39Z (GMT) No. of bitstreams: 2 Tese - Fernanda Ribeiro Santana - 2012.pdf: 12111889 bytes, checksum: 84cf2d3d0d514483cc202fde5fa79301 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-03-09T14:09:39Z (GMT). No. of bitstreams: 2 Tese - Fernanda Ribeiro Santana - 2012.pdf: 12111889 bytes, checksum: 84cf2d3d0d514483cc202fde5fa79301 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-05-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Aim: To evaluate in vitro the influence of root canal instrumentation techniques, endodontic irrigants, endodontic sealers and artificial accelerated aging on fibreglass post bond strength to bovine intraradicular dentine. Methodology: Part 1. 120 bovine incisors were divided into 12 experimental groups (n=10) resulting from the interaction among 3 study factors: root canal instrumentation technique (RCPSS- root canal preparation with stainless steel instruments - KFile; RCPNiTi- root canal preparation with K3 Nickel-Titanium instruments), endodontic irrigant (NaOCl- 1% sodium hypochlorite; CHX- 2% chlorhexidine; O3- 1.2% ozonated water) (in all samples 17% EDTA was used to remove the smear layer) and specimens artificial accelerated aging (Immediate, test with no aging; Mediate, test performed after 2 months of water storage at 37°C). After root canal preparation, endodontic filling was not performed. Fibreglass posts were cemented with self-adhesive resin cement (RelyX U100, 3M-ESPE) and roots were cross-sectioned to obtain two slices of each third. Samples were submitted to micropush-out test and bond strength values (MPa) were analyzed by ANOVA in a split-plot arrangement and Tukey’s test (α = 0.05). Failure modes were evaluated under a confocal microscope. Part 2. 60 bovine incisors were divided into 6 experimental groups (n=10) resulting from the interaction between 2 study factors: endodontic sealer (Sx- Sealapex; S26- Sealer 26; AHAH Plus) and specimens artificial accelerated aging (Immediate, test with no aging; Mediate, test performed after 2 months of water storage at 37°C). Two control groups were employed (without root canal filling), represented by groups RCPNiTiNaOCl immediate and RCPNiTiNaOCl mediate of part 1 of the present study. In the six experimental groups, root canals were prepared 1mm from the apex with K3 Nickel-Titanium instruments associated with 1% sodium hypochlorite irrigation and 17% EDTA. They were then filled with gutta-percha and the specific sealer of each group, using the lateral compaction technique. Fibreglass posts were cemented with self-adhesive resin cement (RelyX U100, 3M-ESPE) and roots were cross-sectioned to obtain two slices of each third. Abstract xx Samples were submitted to micropush-out test and bond strength values (MPa) were submitted to ANOVA in a split-plot arrangement and Tukey’s test (α = 0,05). Comparisons with control groups were made using Dunnet test (α = 0.05). Failure modes were evaluated under a confocal microscope. Results: Part 1. In specimens submitted to water artificial aging, RCPNiTi presented higher bond strength values than RCPSS in apical third irrigated with NaOCl or CHX. Irrigation with NaOCl resulted in higher bond strength than O3. Artificial aging resulted in significant bond strength increase, except for middle and apical thirds of RCPSSO3 and apical of RCPNiTiO3. Bond strength significantly reduced in apical third. The prevalence of adhesive cement-dentine failure was verified in all groups. Part 2. Endodontic sealers showed no significant differences among them, however they presented significantly lower bond strength values than control groups (without filling), except in cervical third of groups tested immediately. Artificial aging did not interfere on bond strength to intraradicular dentine. There was a significant decrease on bond strength from cervical to apical third. The prevalence of adhesive cement-dentine failure was verified in all groups. Conclusions: Part 1. Root canal preparation with NiTi instruments associated with NaOCl irrigation and EDTA increased the bond strength of fiberglass posts cemented with self-adhesive resin cement to intraradicular dentine. Part 2. Endodontic sealers interfered negatively on bonding of fibreglass posts cemented with self-adhesive resin cement to intraradicular dentine. / Objetivo: Analisar in vitro a influência das técnicas de instrumentação do canal radicular, dos irrigantes e cimentos endodônticos e do envelhecimento artificial acelerado na resistência de união do pino de fibra de vidro à dentina intrarradicular em dentes bovinos. Metodologia: Parte 1. Cento e vinte incisivos bovinos foram divididos em doze grupos experimentais (n=10) resultantes da interação entre três fatores em estudo: técnica de instrumentação do canal radicular (PAI – preparo do canal radicular com instrumentos de aço inoxidável - K-File; PNiTi – preparo do canal radicular com instrumentos de Níquel-Titânio - K3); irrigante endodôntico (NaOCl- hipoclorito de sódio 1%; CHX- clorexidina 2%; O3- água ozonificada 1,2%) (em todas as amostras o EDTA 17% foi utilizado para a remoção de smear layer) e envelhecimento artificial acelerado dos espécimes (Imediato, teste sem envelhecimento; Mediato, teste após 2 meses de envelhecimento em água a 37°C). Após o preparo dos canais radiculares não foi realizada a obturação endodôntica. Pinos de fibra de vidro foram cimentados com cimento resinoso auto-adesivo (RelyX U100, 3M-ESPE) e as raízes foram seccionadas para obtenção de duas fatias de cada terço. As amostras foram submetidas ao teste de micropush-out e os dados de resistência de união (MPa) foram analisados por ANOVA com parcela subdividida e teste de Tukey (α = 0,05). Os padrões de falha foram avaliados por meio de microscopia confocal. Parte 2. Sessenta incisivos bovinos foram divididos em seis grupos experimentais (n=10) resultantes da interação entre dois fatores em estudo: cimento endodôntico (SX- Sealapex; S26- Sealer 26; AH- AH Plus) e envelhecimento artificial acelerado dos espécimes (Imediato, teste sem envelhecimento; Mediato, teste após 2 meses de envelhecimento em água a 37°C). Foram empregados dois grupos controles (sem obturação do canal radicular) representados pelos grupos PNiTiNaOCl imediato e PNiTiNaOCl mediato da parte 1 do presente estudo. Nos seis grupos experimentais os canais radiculares foram preparados 1mm aquém do ápice com instrumentos de Níquel-Titânio - K3 associado a Resumo xviii irrigação com NaOCl 1% e EDTA 17%. Em seguida, foram obturados com gutapercha e o cimento endodôntico específico de cada grupo, usando a técnica de condensação lateral. Pinos de fibra de vidro foram cimentados com cimento resinoso auto-adesivo (RelyX U100, 3M-ESPE) e as raízes foram seccionadas para obtenção de duas fatias de cada terço. As amostras foram submetidas ao teste de micropush-out e os dados de resistência de união (MPa) foram analisados por ANOVA com parcela subdividida e teste de Tukey (α = 0,05). Comparações com os grupos controles foram feitas pelo teste de Dunnet (α =0,05). Os padrões de falha foram avaliados por meio de microscopia confocal. Resultados: Parte 1. Nos espécimes submetidos ao envelhecimento artificial em água, PNiTi apresentou maiores valores de resistência de união que PAI no terço apical irrigado com NaOCL ou CHX. A irrigação com NaOCL resultou em maior resistência de união comparada a O3. O envelhecimento artificial resultou em aumento significante da resistência de união, exceto para os terços médio e apical de PAIO3 e apical de PNiTiO3. A resistência de união reduziu significativamente no terço apical. A prevalência de falha adesiva cimentodentina foi verificada em todos os grupos. Parte 2. Os cimentos endodônticos não mostraram diferenças significantes entre si, entretanto apresentaram valores de resistência de união significativamente menores que os grupos controles (sem obturação), exceto no terço cervical dos grupos testados imediatamente. O envelhecimento artificial não interferiu na resistência de união à dentina intrarradicular. Houve uma diminuição significante na resistência de união do terço cervical para o apical. A prevalência de falha adesiva cimentodentina foi verificada em todos os grupos. Conclusões: Parte 1. O preparo do canal radicular com instrumentos de NiTi associado a irrigação com NaOCl e uso do EDTA aumentou a resistência de união de pinos de fibra de vidro cimentados com cimento auto-adesivo à dentina intrarradicular. Parte 2. Os cimentos endodônticos interferiram negativamente na união de pinos de fibra de vidro cimentados com cimento auto-adesivo à dentina intrarradicular.
85

Efficacy of propolis against fusobacterium nucleatum biofilm

Griglione, Anthony Leonard January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The primary goal of root canal treatment is to eliminate microbes from the root canal system, which is the cause of pulpal and periapical infections. Research shows that after a single visit of chemomechanical debridement microbes continue to remain within the canal system. An interappointment medication step has been advocated to maximize potential elimination of microbes within the root canal system. Previous studies have shown propolis to be antibacterial against common endodontic microbes. Studies have shown trends in different microbes being present in primary verus secondary endodontic infections. The majority of literature has focused on the efficacy of propolis against Enterococcus faecalis, a microbe commonly implicated in secondary endodontic 95 infections. The aim of this study was to demonstrate the efficacy of propolis against Fusobacterium nucleatum, a microbe commonly found in primary endodontic infections. This study aims to demonstrate the efficacy of propolis against a bacterium of primary endodontic infections (F. nucleatum) as well as against microbial biofilm to further support its potential use as a novel intracanal medicament. Dilutions of propolis were added to cultures of F. nucleatum in microtiter plates in a range from 390 μg/ml to 50,000 μg/ml. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and the minimum biofilm inhibitory concentration (MBIC) were determined. The MIC was determined of the total solution (biofilm+planktonic), planktonic, and biofilm (MBIC) after a 48-hour incubation period. The MBIC was determined by fixing biofilm to the wells and using crystal violet staining with spectrophotometry. The MBC was examined by plating solution from each concentration test well and reading the plates after 48 hours of incubation. The results show that the MIC of the total (biofilm+planktonic) appears to occur at a concentration of 6250 μg/ml. The MBIC appears to occur at the concentration of 1562.5 μg/ml. The planktonic results exhibit no significant difference in test and control wells. There was no MBC at any of the test concentrations. The propolis appears to inhibit bacterial growth and biofilm formation but does not appear to be bactericidal at any of the tested concentrations. The results of this study indicate that propolis has an MIC and MBIC when tested in vitro against F. nucleatum, although it does not show an MBC. There appears to be potentially significant interaction of propolis with biofilm as displayed by the lower concentration needed to exibit inhibitory effects on biofilm formation. This information 96 may contribute to the ability to develop a proper concentration of propolis to use in vivo when treating endodontic infections.
86

Efeito da irrigação prévia na adesão de cimentos resinosos autoadesivos ao canal radicular na cimentação de pinos de fibra de vidro / Effect of previous irrigation on the adhesion of self-adhesive resin cements to the root canal in the cementation of glass fiber posts

Jitumori , Renata Terumi 21 February 2018 (has links)
Submitted by Eunice Novais (enovais@uepg.br) on 2018-07-24T14:32:21Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) RENATA TERUMI JITUMORI.pdf: 3093609 bytes, checksum: 92de6bf22e06953ec3a932faaf478f71 (MD5) / Made available in DSpace on 2018-07-24T14:32:21Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) RENATA TERUMI JITUMORI.pdf: 3093609 bytes, checksum: 92de6bf22e06953ec3a932faaf478f71 (MD5) Previous issue date: 2018-02-21 / Avaliou-se o efeito da irrigação prévia na adesão de cimentos resinosos autoadesivos ao canal radicular na cimentação de pinos de fibra de vidro (PFV). Foram utilizados 120 dentes permanentes unirradiculares, os quais tiveram suas coroas removidas e suas raízes tratadas endodonticamente. Após uma semana, foi realizado o preparo padronizado dos condutos para posterior cimentação dos PFV. Nesse momento, as raízes foram divididas aleatoriamente em dez grupos, de acordo com a combinação dos seguintes fatores: cimento resinoso autoadesivo – RelyX U200 (3M ESPE) e Multilink Speed (Ivoclar Vivadent), e agente irrigante aplicado previamente à cimentação dos PFV – água destilada (AD), NaOCl 2,5% (Na), EDTA 17% (ED), ácido poliacrílico 26% (AP) e associação EDTA 17% + NaOCl 2,5% (EN). Duas raízes de cada agente irrigante foram utilizadas para avaliação do grau de desobliteração dos túbulos dentinários (DeTd) por microscopia eletrônica de varredura (MEV). Após a cimentação dos PFV, sete raízes por grupo foram avaliadas em resistência de união (RU) pelo teste de push-out, quatro em nanoinfiltração (NI) por MEV e microdureza Vickers (VHN); para esse propósito cada raiz foi seccionada transversalmente em seis fatias. Os dados obtidos da DeTd foram submetidos a Kruskall Wallis e Student-Newman-Keuls (α=0,05) e dos testes de RU, NI e VHN a ANOVA dois fatores e Tukey (α=0,05). Na avaliação da DeTd, os agentes que promoveram maior abertura dos tubúlos dentinários foram ED, AP e EN. Para o cimento RelyX U200, o Na, AD e ED obtiveram os maiores valores de RU e VHN; enquanto que para o Multilink Speed esses valores foram superiores no grupo irrigado com AD. Para ambos os cimentos, o AP apresentou valores inferiores e a associação EN valores intermediários de RU e VHN. Não houve diferença estatística significante nos resultados de NI (p>0,05). Pode-se concluir que para cada agente cimentante deve haver um protocolo de irrigação prévia ideal na cimentação de pinos de fibra de vidro ao canal radicular. / It was evaluated the effect of previous irrigation on the adhesion of on the adhesion of self-adhesive resin cements to the root canal in the cementation of glass fiber posts. A total of 120 unirradicular permanent teeth were used, which had their crowns removed and their roots treated endodontically. After one week, the standard preparation of the post space was made for the cementation of the GFP. At this time, the roots were randomly divided into ten groups, according to the combination of the following factors: self-adhesive resin cement - RelyX U200 (3M ESPE) and Multilink Speed (Ivoclar Vivadent), and irrigating agent applied prior to GFP cementation - distilled water (DW), 2.5% NaOCl (Na), 17% EDTA (ED), 26% polyacrylic acid (PA) and 17% EDTA followed by 2.5% NaOCl (EN). Two roots of each irrigating agent were used for evaluation the degree of open dentinal tubules (ODeT) by scanning electron microscopy (SEM). After the cementation of the GFP, seven roots per group were evaluated in bond strength (BS) by the push-out test, four in nanoleakage (NL) by SEM and in Vickers microhardness (VHN); for this propose each root was sectioned transversely into six slices. The data obtained from ODeT were submitted to Kruskall Wallis and Student-Newman-Keuls (α=0.05) and from the tests of BS, NL and VHN to ANOVA two-way and Tukey (α=0.05). In the evaluation of the ODeT, the agents that promoted greater opening of the dentin tubules were ED, PA and EN. For RelyX U200 cement, the Na, DW and ED obtained the highest values of BS and VHN; while for Multilink Speed these values were higher in the group irrigated with DW. For both cements, the PA presented lower values and the association EN intermediate values of BS and VHN. There was no statistically significant difference in NL results (p>0.05). It can be concluded that for each cementing agent there must be an optimal prior irrigation protocol for the cementation of glass fiber posts to the root canal.
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Análise química do precipitado formado na reação entre hipoclorito de sódio e digluconato de clorexidina / Chemical analysis of the precipitate formed by mixing sodium hypochlorite and chlorhexidine digluconate

Brum, Thiago Cardoso Bulhões 14 August 2012 (has links)
O digluconato de clorexidina reage com o hipoclorito de sódio formando um precipitado, que segundo a literatura, é composto por para-cloroanilina (PCA), ou por para-clorofenil uréia (PCU) e para-clorofenilguanidil-1,6-diguanidil-hexano (PCGH). Este estudo visou analisar quimicamente os produtos formados e a presença de PCA no precipitado. Para isso, foi realizada a reação de 50 mL de solução de hipoclorito de sódio a 5% (NaOCl) e de 50 mL de solução de digluconato de clorexidina a 2% (CLX) em proporções iguais (1:1). O precipitado foi separado do sobrenadante e desidratado. A CLX pura, uma amostra do precipitado puro e outra amostra de precipitado com adição de PCA foram diluídas em dimetilsulfóxido deuterado e analisados em ressonância magnética nuclear 1D 1H (RMN) para verificar, por comparação, a presença da PCA no precipitado e para obtenção dos deslocamentos químicos dos produtos presentes no precipitado. Outra amostra do precipitado, de solução de CLX e de PCA foram separadas em cromatografia líquida de alta eficiência e analisadas em espectrômetro de massa (HPLC-ESI-MS) para identificação dos pesos moleculares dos compostos. A comparação do espectro do precipitado puro e do espectro do precipitado com adição de PCA permitiu analisar que o dubleto presente na região dos compostos aromáticos, referente à PCA, não está presente no espectro do precipitado puro demonstrando que não há PCA no precipitado. A análise do espectro de RMN do precipitado puro sugere que há formação de compostos com um e dois anéis aromáticos. Os espectros de massa permitem sugerir que há quebra da molécula de CLX, pelo hipoclorito de sódio, em sítios específicos (grupo biguanidil) que resultam na formação de fragmentos da molécula de clorexidina que se reorganizam formando oligômeros, ou seja, moléculas em que algumas unidades se repetem e, uma vez formadas, são estáveis e insolúveis em água. É possível concluir que no precipitado não há presença de PCA, sugerindo-se que haja PCGH e outros compostos com pesos moleculares maiores que o da clorexidina, denominados, neste estudo, C3, C4, C5, C6 e C7. / The reaction between chlorhexidine digluconate and sodium hypochlorite result in a precipitate, which according to the literature, is composed of para-chloroaniline (PCA), or para-chlorophenylurea (PCU) and para-chlorophenylguanidyl-1,6- diguanidyl-hexane (PCGH). The purpose of this study was to determine the chemical composition, the relative molecular weight of the compounds and whether PCA is formed in the precipitate. A 2% chlorhexidine digluconate solution was mixed in a 1:1 ratio with 5% NaOCl solution producing the precipitate. It was centrifuged, separed from the supernatant and dried. Pure CHX, the precipitate, as well as a mixture of precipitate and pure PCA were dissolved in deuterated dimetilsulfoxide and then analyzed using one-dimensional 1H nuclear magnetic resonance (MNR) to determine whether PCA was formed and to obtain precipitates chemical shifts. Other precipitate, CHX digluconate solution and PCA samples were analized using high performance liquid chromatography - electrospray ionization - mass spectrometry (HPLC-ESI-MS). Comparing the spectrum of the precipitate alone and precipitate with PCA allow to identify that PCA doublet peaks are not present in the spectrum of the precipitate alone, demonstrating that there are no PCA in the precipitate. NMR spectrum of the precipitate alone suggests that there is compounds with one and two aromatic rings. Mass spectra suggests that breaks in chlorhexidine molecule on specific sites (biguanidil groups), by sodium hypochlorite, results in fragments that forms oligomers molecules in wich some units are repeated and, once formed, are stable and insoluble in water. On the basis of this study, there is no PCA in the precipitate and suggesting that there may be other compounds like PCGH and others compounds, all of which are bigger in size than CHX, called, in this study, C3, C4, C5, C6 and C7.
88

Análise química do precipitado formado na reação entre hipoclorito de sódio e digluconato de clorexidina / Chemical analysis of the precipitate formed by mixing sodium hypochlorite and chlorhexidine digluconate

Thiago Cardoso Bulhões Brum 14 August 2012 (has links)
O digluconato de clorexidina reage com o hipoclorito de sódio formando um precipitado, que segundo a literatura, é composto por para-cloroanilina (PCA), ou por para-clorofenil uréia (PCU) e para-clorofenilguanidil-1,6-diguanidil-hexano (PCGH). Este estudo visou analisar quimicamente os produtos formados e a presença de PCA no precipitado. Para isso, foi realizada a reação de 50 mL de solução de hipoclorito de sódio a 5% (NaOCl) e de 50 mL de solução de digluconato de clorexidina a 2% (CLX) em proporções iguais (1:1). O precipitado foi separado do sobrenadante e desidratado. A CLX pura, uma amostra do precipitado puro e outra amostra de precipitado com adição de PCA foram diluídas em dimetilsulfóxido deuterado e analisados em ressonância magnética nuclear 1D 1H (RMN) para verificar, por comparação, a presença da PCA no precipitado e para obtenção dos deslocamentos químicos dos produtos presentes no precipitado. Outra amostra do precipitado, de solução de CLX e de PCA foram separadas em cromatografia líquida de alta eficiência e analisadas em espectrômetro de massa (HPLC-ESI-MS) para identificação dos pesos moleculares dos compostos. A comparação do espectro do precipitado puro e do espectro do precipitado com adição de PCA permitiu analisar que o dubleto presente na região dos compostos aromáticos, referente à PCA, não está presente no espectro do precipitado puro demonstrando que não há PCA no precipitado. A análise do espectro de RMN do precipitado puro sugere que há formação de compostos com um e dois anéis aromáticos. Os espectros de massa permitem sugerir que há quebra da molécula de CLX, pelo hipoclorito de sódio, em sítios específicos (grupo biguanidil) que resultam na formação de fragmentos da molécula de clorexidina que se reorganizam formando oligômeros, ou seja, moléculas em que algumas unidades se repetem e, uma vez formadas, são estáveis e insolúveis em água. É possível concluir que no precipitado não há presença de PCA, sugerindo-se que haja PCGH e outros compostos com pesos moleculares maiores que o da clorexidina, denominados, neste estudo, C3, C4, C5, C6 e C7. / The reaction between chlorhexidine digluconate and sodium hypochlorite result in a precipitate, which according to the literature, is composed of para-chloroaniline (PCA), or para-chlorophenylurea (PCU) and para-chlorophenylguanidyl-1,6- diguanidyl-hexane (PCGH). The purpose of this study was to determine the chemical composition, the relative molecular weight of the compounds and whether PCA is formed in the precipitate. A 2% chlorhexidine digluconate solution was mixed in a 1:1 ratio with 5% NaOCl solution producing the precipitate. It was centrifuged, separed from the supernatant and dried. Pure CHX, the precipitate, as well as a mixture of precipitate and pure PCA were dissolved in deuterated dimetilsulfoxide and then analyzed using one-dimensional 1H nuclear magnetic resonance (MNR) to determine whether PCA was formed and to obtain precipitates chemical shifts. Other precipitate, CHX digluconate solution and PCA samples were analized using high performance liquid chromatography - electrospray ionization - mass spectrometry (HPLC-ESI-MS). Comparing the spectrum of the precipitate alone and precipitate with PCA allow to identify that PCA doublet peaks are not present in the spectrum of the precipitate alone, demonstrating that there are no PCA in the precipitate. NMR spectrum of the precipitate alone suggests that there is compounds with one and two aromatic rings. Mass spectra suggests that breaks in chlorhexidine molecule on specific sites (biguanidil groups), by sodium hypochlorite, results in fragments that forms oligomers molecules in wich some units are repeated and, once formed, are stable and insoluble in water. On the basis of this study, there is no PCA in the precipitate and suggesting that there may be other compounds like PCGH and others compounds, all of which are bigger in size than CHX, called, in this study, C3, C4, C5, C6 and C7.
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Antibacterial efficacy of 0.12-percent and 2.0-percent chlorhexidine gluconate at 37˚C and 46˚C against enterococcus faecalis

Thiessen, Craig B.D., 1978- January 2010 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this study was to investigate the antibacterial efficacy of 0.12-percent and 2.0-percent chlorhexidine gluconate (CHX) on eliminating Enterococcus faecalis from dentinal tubules, and whether this antibacterial effect was enhanced by heat. To date there have been no published articles that describe the heating of 2.0-percent CHX and its antimicrobial efficacy and clinical relevance towards E. faecalis within dentinal tubules in root canal systems. Ninety-five human extracted, single rooted, maxillary, anterior teeth were used to prepare dentin disk specimens. After proper sterilization, a 2.5-mm ISO-sized diameter lumen was prepared, and then the canals were filled with brain-heart infusion (BHI) broth infected with E. faecalis. The BHI was removed and the specimens in equally divided groups were rinsed with sterile saline and filled with saline, or 0.12 percent CHX or 2.0 percent CHX at ambient temperature (24°C) or experimental temperature (46°C) and incubated at oral temperature (37°C) or the experimental temperature (46°C), respectively. The specimens were frozen to -70˚C and pulverized in liquid nitrogen. Serial dilutions were prepared of 1:100 and 1:1000 and spiral plated on BHI agar plates in duplicate. They were incubated, and the number of bacterial colonies was recorded 24 hours later for data analysis. A two-way analysis of variance (ANOVA), with factors for solution, solution temperature, and the solution-by-temperature interaction was used to determine antibacterial efficacy. Pair-wise comparisons between groups were examined for significance using the Fisher’s Protected Least Significant Differences Method. The E. faecalis CFU were log-transformed to satisfy the assumptions required for the ANOVA. The results of this investigation demonstrated no statistically significant difference with the addition of heat to either test irrigation solution regarding the elimination of E. faecalis from dentinal tubules within the root canal system. There was a statistically significant difference in the antibacterial efficacy of CHX against E. faecalis in comparison with the concentration tested. A higher concentration of 2.0-percent CHX demonstrated a significantly higher antibacterial efficacy against E. faecalis compared with 0.12-percent CHX, and likewise with the saline control. It can be concluded that the use of a higher concentration of 2.0-percent CHX is advantageous as a final irrigation solution after copious amounts of NaOCl and EDTA have been utilized for effective antimicrobial efficacy and substantivity.
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Effect of Antibiotic Pastes on Chemical Structure and Microhardness of Radicular Dentin

Prather, Blake January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: Regenerative endodontic therapy in immature teeth with necrotic pulps triggers continued root development, thereby improving the prognosis of these teeth. Disinfection of the canal is accomplished with an intracanal medicament, such as triple antibiotic paste (TAP) composed of metronidazole, ciprofloxacin, and minocycline. A modified triple antibiotic paste (MTAP) that replaces minocycline with clindamycin has recently been suggested to avoid the tooth discoloration and potential demineralization from minocycline. The effect these pastes have on radicular dentin is unknown. Objectives: The aim of this study was to investigate the effects of two intracanal medicaments used during endodontic regeneration, TAP and MTAP, at concentrations of 1 g/mL and 1 mg/mL, on the microhardness and chemical structure of radicular dentin. Materials and Methods: Roots from extracted, unrestored, non-carious human premolar teeth were sectioned. An antibiotic paste (MTAP or TAP) or sterile water (control) was applied to treatment groups and stored for four weeks in 80-percent humidity at 37 °C. The effect of each paste on the microhardness of radicular dentin was measured using a Vickers Microhardness Tester (n = 17) to take three pretreatment and post-treatment measurements at both 500 µm and 1000 µm from the pulp-dentin interface. The chemical structure was assessed from dentin specimens treated with the same medicaments or sterile water for four weeks. After treatment, three measurements were taken on each specimen using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy to measure the phosphate/amide I ratios of dentin (n = 7). Results: The 1 g/mL of TAP or MTAP and the 1 mg/mL methylcellulose-based TAP caused significant reduction in microhardness of roots compared with untreated control roots at 500 µm and 1000 µm from the pulp-dentin interface. Furthermore, the methylcellulose-based 1 mg/mL TAP and MTAP caused significantly less reduction in microhardness compared with 1 g/mL TAP and MTAP. The 1 g/mL of TAP and DAP caused significantly lower phosphate/amide I ratios compared with other groups. Conclusion: The use of methylcellulose based 1 mg/mL of TAP and MTAP may minimize the reduction in microhardness of roots compared with the currently used 1 g/mL concentration of these antibiotics.

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