Routine products are used and procedures are followed in order to prevent and minimize the bacterial contamination of the surgical wound, and thus reduce the risk of postoperative wound infections. The overall aim of this thesis was to investigate the effect of different preoperative skin preparation before cardiac surgery. In study I, 10 healthy volunteers were compared in time to recolonization of the skin and bacterial growth with or without plastic adhesive drape. Bacterial samples were taken as paired samples on both side of the sternum. Plastic drape on disinfected skin seems to hasten recolonization compared with bare skin. In study II, 135 cardiac surgery patients were comparing plastic adhesive drape versus bare skin on the chest regarding intra-operative bacterial growth. Plastic adhesive drape did not reduce the bacterial recolonization or wound contamination, P. acnes colonizes males more often than females and P. acnes is not affected by disinfection with 0.5% chlorhexidine in ethanol. Study III, compared the leg harvesting site with or without microbal skin sealant in 135 CABG patients regarding intraoperative bacterial growth and postoperative wound infection. Almost no bacterial growth was found during surgery regardless of the use of microbial skin sealant and bare skin. A high incidence of postoperative wound infections (16.8%) in 2 month follow up was present and SSI was largely caused by S. aureus, i.e. other bacterial species than observed intraoperative. Study IV, a descriptive study using phenotypic and genotypic methods investigate susceptibility to chlorhexidine among S. epidermidis indicating that S. epidermidis isolates following preoperative skin disinfection are sensitive tochlorhexidine.

No description available.

L'objectif de cette thèse a été de développer une forme galénique pour l'administration locale d'antiseptiques dans le traitement de lésions buccales. De par la présence de la salive et des mécanismes de déglutition et de mastication, le temps de séjour des principes actifs dans la cavité buccale est court ce qui conduit à une faible efficacité thérapeutique locale. Ainsi, l'encapsulation de principes actifs dans des microparticules mucoadhésives à base de pectine a été envisagée. Deux antiseptiques couramment utilisés dans le traitement des lésions buccales ont été retenus : la chlorhexidine (CX) et l'hexétidine (HX). Le procédé utilisé pour l'encapsulation de l'HX consiste en la gélification ionique de pectine contenue dans la phase aqueuse d'une émulsion double L/H/L par l'ajout de Ca2+. L'influence des paramètres de procédé et de formulation sur l'efficacité d'encapsulation de l'actif a été étudiée à l'aide d'un plan d'expériences. Dans le cas de la CX, les essais préliminaires ont mis en évidence des interactions entre l'actif et la pectine conduisant à la gélification du polymère sans utilisation d'ions Ca2+. Des études physicochimiques ont donc été réalisées afin d'investiguer ces interactions et de comparer le mécanisme de gélification observé à celui de la gélification ionique de la pectine par les ions Ca2+. Des mécanismes de gélification similaires ont été observés pour ces deux cations divalents avec de plus fortes interactions entre la pectine et la CX. Puis des microparticules de pectine et CX ont été développées par prilling sans ajout d'ions. L'influence de l'ajout de Zn2+ dans la formulation sur les propriétés des microparticules a finalement été étudiée / The aim of this project was to develop a dosage form for antiseptics local administration in order to treat buccal injuries. Due to the presence of saliva in association with swallowing and chewing, actives substances have a short retention time in the buccal cavity and thus a low therapeutic efficacy. To resolve this problem, the encapsulation of active agents in pectin mucoadhesive microparticles was studied. For this purpose, two widely used antiseptics have been selected: chlorhexidine and hexetidine. Hexetidine encapsulation was obtained by performing calcium-induced ionic gelation of the pectin aqueous solution involved in a double emulsion L/H/L. The influence of both process and formulation parameters on encapsulation efficiency were studied by using an experimental design. In the case of chlorhexidine, preliminary experiments highlighted interactions between the active substance and pectin leading to polymer gelation without the use of additional Ca2+ dications. Hence, pectin/chlorhexidine interactions were investigated by several physico-chemical studies and the corresponding gelation mechanism was compared to that of the well-known pectin ionic gelation induced by Ca2+ ions. Similar binding processes were observed for both divalent ions, though stronger interactions were observed with chlorhexidine. Pectin/chlorhexidine microparticles were then developed by prilling (vibrational jet technique) without additional Ca2+ ions. Finally, the influence of zinc dications addition in the formulation on the microparticle properties (size, encapsulation efficiency, drug release kinetics) was evaluated

Neste trabalho, objetivou-se avaliar as propriedades físicas e microbiológicas de resinas acrílicas a base de polimetilmetacrilato após a incorporação de sal de diacetato de clorexidina (CDA) às mesmas. Para tal, foram confeccionados corpos de prova (CDPs) com as resinas VIPI COR e Duralay, sem e com incorporação de 0,5%; 1,0% e 2,0% de CDA, totalizando 8 grupos. A cromatografia líquida foi utilizada para mensurar a liberação de CDA pelas resinas acrílicas, e ainda, mensurar sua lixiviação de monômeros residuais.Para isso, os CDPs foram armazenados individualmente em placas para cultura celular de 24 poços contendo 1 ml de água destilada estéril em cada poço. Após tempo de armazenagem de 2 horas, 7 dias, 14 dias, 21 dias e 28 dias, a 37oC, a solução foi retirada e a liberação de clorexidina ou monômeros residuais foi avaliada utilizando-se HPLC associado a espectrometria ultravioleta. A atividade antifúngica para C. albicans foi avaliada utilizando teste de difusão em ágar, no qual os CDPs foram colocados em placas de BHI previamente inoculadas com C. albicans, com medição do halo de inibição após 48 horas de incubação a 37C. A análise do grau de conversão das resinas se deu através da técnica de espectroscopia de infravermelho transformada de Fourier FTIR utilizando-se uma amostra de resina não polimerizada de cada grupo e realizados 4 scans de absorbância. Para a mensuração da sorção de água por parte das resinas contendo CDA, foram confeccionados 10 corpos de prova para cada grupo, que foram posicionados em suporte dentro de dessecador a 37C para remoção de umidade intrínseca (m1) e depois imersos em 100 ml de água deionizada por 7 dias a 37C, tendo a água trocada diariamente. Após este intervalo, os corpos foram secos para obter a nova massa da resina (m2). As massas obtidas foram incluídas em fórmula matemática para obtenção do grau de sorção. Após obtenção dos resultados, quando comparou-se o halo inibição entre os grupos testados e de mesma marca, apenas as análises entre grupo CDA 2% x grupo CDA 1% e entre CDA 1% x CDA 0,5% não apresentaram diferenças significantes. Quanto a liberação de CDA, a análise de variância demonstrou que dois dos três fatores avaliados (concentração do fármaco e tempo de armazenagem) alteram de maneira significativa a taxa de liberação da clorexidina (p<0,0001), entretanto a marca do material pareceu não influenciar de maneira significativa na liberação do fármaco. Quanto ao grau de conversão, os valores obtidos não foram significantes e apresentou-se menor apenas nos grupos com CDA 2% . Para ambas a sorção de água aumentou conforme a incorporação do sal cresceu e houve aumento significativo nas concentrações de 1.0% e 2.0%. Podemos concluir que a incorporação da clorexidina às resinas a base de PMMA: é capaz de inibir o crescimento de C. albicans; não alterou o grau de conversão das resinas testadas; não altera a liberação de monômeros residuais; e, altera a sorção de água das resinas acrílicas a base de PMMA quando concentrações maiores de CDA são adicionadas. / This work aimed to evaluate physical and microbiological properties of PMMA acrylic resins after incorporating chlorhexidine diacetate salt (CDA) to them . For that, specimens ( CDPs ) were made with resins VIPI COR and Duralay , with and without incorporation of 0.5 % , 1.0 % and 2.0 % of CDA , totaling 8 groups . The liquid chromatography was used to measure the release of CDA by acrylic resins , and also to measure leaching of residual monomers . For that, CDPs were stored individually in cell culture plates to 24 well containing 1 ml of sterile distilled water in each well. Storage time after 2 hours , 7 days, 14 days, 21 days and 28 days at 37 C , the solution was removed and release of residual monomers or chlorhexidine was evaluated by using ultraviolet spectrometry combined with HPLC. The antifungal activity to C. albicans was evaluated using the agar diffusion method , in which the CDPs were placed on BHI plates inoculated with C. albicans with measuring the zone of inhibition after 48 hours incubation at 37 C. The analysis of the resins conversion degree is given by infrared spectroscopy Fourier transform - FTIR using an uncured resin sample in each group and 4 scans performed absorbance . For the measurement of resins containing CDA s water sorption, 10 specimens were prepared for each group , which were placed in support within desiccator 37 C to remove intrinsic ( m1 ) and then immersed moisture in 100 ml deionized water for 7 days at 37 C , and the water was changed daily. After this interval , the specimens were dried to obtain the new resins weight ( m2 ) . The masses obtained were included in the mathematical formula for the degree of sorption. After obtaining results, when compared the inhibition halo between the tested groups and the same brand , only the analyzes between group CDA2 % x CDA 1 % group and from CDA 1 % x CDA0.5 %,showed no significant differences . About the release of CDA , analysis of variance showed that two of the three factors assessed ( drug concentration and storage time ) significantly change the rate of release of chlorhexidine ( p < 0.0001 ) , however the material mark seemed not significantly influence the drug release . About the conversion degree , the values were not significant and were minor only in groups with CDA 2 % . For both water sorption increased with the incorporation of salt grew and there was significant increase in concentrations of 1.0 % and 2.0 % . We conclude that the incorporation of chlorhexidine to the PMMA based resin : is able to inhibit the growth of C. Albicans ; did not alter the degree of conversion of the resins tested , does not alter the release of residual monomers , and changes the water sorption of the base PMMA acrylic resins when CDA concentrations are incorporated.

Resinas macias para reembasamento de próteses são largamente utilizadas após cirurgias para estabilizarem a prótese e condicionarem o tecido, aguardando a completa cicatrização. É importante que o material não seja facilmente colonizado por biofilme oral e se possível, evite a contaminação do sítio cirúrgico. Objetivou-se avaliar o efeito da incorporação de clorexidina às resinas acrílicas macias para o reembasamento de próteses totais, através de análises de liberação, citotoxicidade e efeito inibitório de um biofilme de C. albicans. Foram confeccionados corpos de provas (CDPs) com as resinas Trusoft e Coe-soft, com incorporação de 0%, 0,5%, 1,0% e 2,0% de clorexidina, totalizando 8 grupos. A liberação de clorexidina foi avaliada através da mensuração da mudança na densidade óptica da solução de armazenamento, na qual ficaram imersos os CDPs, por espectrometria UV, a cada 48 horas, durante 40 dias. A citotoxicidade celular foi avaliada em fibroblastos (linhagem L929), que ficaram 24 horas em contato com meio de cultura no qual os CDPs ficaram previamente imersos, pela técnica de absorção de corante vermelho neutro após 24, 48 e 72 horas e semanalmente até o 28 dia. E, por fim, a atividade antifúngica contra a C. albicans (ATCC 10231) foi avaliada de duas maneiras: (1) teste de difusão em ágar, no qual os CDPs foram colocados em placas de BHI previamente inoculadas com C. albicans, com medição do halo de inibição após 48 horas de incubação a 37C; (2) a avaliação da inibição da formação de um biofilme de C. albicans sobre a superfície dos CDPs pela quantificação por metil tetrazólio (MTT) a cada 48 horas, durante 22 dias, com leitura feita em espectrofotômetro de UV. Os dados obtidos foram inseridos no programa SigmaStat (versão 3.1, USA) para realizar as análises estatísticas. As diferenças estatísticas foram determinadas por análises de variâncias do tipo ANOVA e todos os procedimentos para comparações múltiplas pareadas foram feitos utilizando-se o método Holm-Sidak, com nível de significância global igual a 0,05. A clorexidina adicionada às resinas testadas foi capaz de ser liberada para o meio de armazenagem, proporcionalmente à quantidade de clorexidina incorporada, porém com diferentes cinéticas de liberação entre as resinas, visto que a Trusoft libera até 71% do total de clorexidina liberada nas primeiras 48 horas e a Coe-soft, até 44%. Ambas as resinas com incorporação de clorexidina apresentaram efeito citotóxico adicional, se comparadas às resinas sem clorexidina, porém para a Coe-soft não houve diferença estatística dos valores, apenas para a Trusoft (p<0,001). Ocorreu formação de halo de inibição proporcionalmente às concentrações de resinas adicionadas, com maiores halos para a resina Trusoft (p<0,001), e sem formação de halo para as resinas sem clorexidina; a inibição da formação de biofilme, realizada somente com a resina Coe-soft, mostrou total inibição durante 8, 12 e 16 dias, para a incorporação de 0,5%, 1,0% e 2,0% respectivamente, sendo uma diminuição estatisticamente significativa (p<0,001) em relação à resina sem incorporação de clorexidina, que não apresentou inibição do biofilme. / Denture soft lining materials are widely used after dental surgeries, tissue conditioning and stabilization of prostheses, until the complete tissue healing. It is important that this material not became easily colonized by oral biofilm and if possible, avoid contamination of the surgical site. The aim of this study was to evaluate the effect of chlorhexidine incorporation into resin-based soft denture lining material, considering the drug release analysis, cytotoxicity and C. albicans biofilm inhibition. Specimens were done using Trusoft and Coe-soft, incorporating 0%, 0.5%, 1.0% and 2.0% of chlorhexidine, totaling eight groups. The chlorhexidine release was evaluated through the measurement of change in optical density of the storage solution, which the specimens were immersed, by UV spectrometry, after every 48 hours for 40 days. The cellular cytotoxicity was evaluated in fibroblasts (strain L929), which were 24 hours in contact with culture medium, in which the specimens were previously immersed, the technique of neutral red dye uptake was used after 24, 48 and 72 hours and weekly until 28th day. Finally, the antifungal activity against C. albicans (ATCC 10231) was evaluated by two different ways: (1) agar diffusion test, in which the specimens were placed over the top of BHI agar plates previously inoculated with C. albicans, and the measurement of inhibition zone was done after 48h of incubation at 37C, (2) C. albicans biofilm inhibition over the specimens surface, which was mensured after every each 48 hours of biofilm and specimens co-incubation, by methyl tetrazolium (MTT), in UV/vis spectrophotometer, during 22 days. Data were analyzed with the SigmaStat software (version 3.1, USA). Statistical differences were determined by analysis of variance ANOVA and all procedures for multiple paired comparisons were made using the Holm-Sidak method, with overall significance level of 0.05. The chlorhexidine added to both resins, Trusoft and Coe-soft, can be released to the storage medium, with a dose-related effect, however the resins presented different release kinetics, since the Trusof released up to 71% of the total amount of the chlorhexidine released within the first 48 hours and Coe-soft release only up to 44%, considering the citotoxic effect, both chlorhexidine incorporated resins showed some extra cytotoxic effect, if compared to resins without chlorhexidine, but for Coe-soft no statistical difference of values was founded, only for Trusoft (p<0.001); considering the C. albicans inhibition, the agar diffusion test values were dose-related for both resins, however with bigger inhibition zones for Trusoft (p<0.001), and without any inhibition for the resins without clorexidine. For the C. albicans biofilm inhibition test, performed only with Coe-soft resin, it was verified a complete inhibition at 8, 12 and 16 days for the incorporation of 0.5%, 1.0% and 2.0% of clorexidine respectively, a statistically significant decrease (p<0.001) if compared to the resin without incorporation of chlorhexidine, which showed no inhibitory effect over the biofilm formation.

Neste trabalho, objetivou-se avaliar as propriedades físicas e microbiológicas de resinas acrílicas a base de polimetilmetacrilato após a incorporação de sal de diacetato de clorexidina (CDA) às mesmas. Para tal, foram confeccionados corpos de prova (CDPs) com as resinas VIPI COR e Duralay, sem e com incorporação de 0,5%; 1,0% e 2,0% de CDA, totalizando 8 grupos. A cromatografia líquida foi utilizada para mensurar a liberação de CDA pelas resinas acrílicas, e ainda, mensurar sua lixiviação de monômeros residuais.Para isso, os CDPs foram armazenados individualmente em placas para cultura celular de 24 poços contendo 1 ml de água destilada estéril em cada poço. Após tempo de armazenagem de 2 horas, 7 dias, 14 dias, 21 dias e 28 dias, a 37oC, a solução foi retirada e a liberação de clorexidina ou monômeros residuais foi avaliada utilizando-se HPLC associado a espectrometria ultravioleta. A atividade antifúngica para C. albicans foi avaliada utilizando teste de difusão em ágar, no qual os CDPs foram colocados em placas de BHI previamente inoculadas com C. albicans, com medição do halo de inibição após 48 horas de incubação a 37C. A análise do grau de conversão das resinas se deu através da técnica de espectroscopia de infravermelho transformada de Fourier FTIR utilizando-se uma amostra de resina não polimerizada de cada grupo e realizados 4 scans de absorbância. Para a mensuração da sorção de água por parte das resinas contendo CDA, foram confeccionados 10 corpos de prova para cada grupo, que foram posicionados em suporte dentro de dessecador a 37C para remoção de umidade intrínseca (m1) e depois imersos em 100 ml de água deionizada por 7 dias a 37C, tendo a água trocada diariamente. Após este intervalo, os corpos foram secos para obter a nova massa da resina (m2). As massas obtidas foram incluídas em fórmula matemática para obtenção do grau de sorção. Após obtenção dos resultados, quando comparou-se o halo inibição entre os grupos testados e de mesma marca, apenas as análises entre grupo CDA 2% x grupo CDA 1% e entre CDA 1% x CDA 0,5% não apresentaram diferenças significantes. Quanto a liberação de CDA, a análise de variância demonstrou que dois dos três fatores avaliados (concentração do fármaco e tempo de armazenagem) alteram de maneira significativa a taxa de liberação da clorexidina (p<0,0001), entretanto a marca do material pareceu não influenciar de maneira significativa na liberação do fármaco. Quanto ao grau de conversão, os valores obtidos não foram significantes e apresentou-se menor apenas nos grupos com CDA 2% . Para ambas a sorção de água aumentou conforme a incorporação do sal cresceu e houve aumento significativo nas concentrações de 1.0% e 2.0%. Podemos concluir que a incorporação da clorexidina às resinas a base de PMMA: é capaz de inibir o crescimento de C. albicans; não alterou o grau de conversão das resinas testadas; não altera a liberação de monômeros residuais; e, altera a sorção de água das resinas acrílicas a base de PMMA quando concentrações maiores de CDA são adicionadas. / This work aimed to evaluate physical and microbiological properties of PMMA acrylic resins after incorporating chlorhexidine diacetate salt (CDA) to them . For that, specimens ( CDPs ) were made with resins VIPI COR and Duralay , with and without incorporation of 0.5 % , 1.0 % and 2.0 % of CDA , totaling 8 groups . The liquid chromatography was used to measure the release of CDA by acrylic resins , and also to measure leaching of residual monomers . For that, CDPs were stored individually in cell culture plates to 24 well containing 1 ml of sterile distilled water in each well. Storage time after 2 hours , 7 days, 14 days, 21 days and 28 days at 37 C , the solution was removed and release of residual monomers or chlorhexidine was evaluated by using ultraviolet spectrometry combined with HPLC. The antifungal activity to C. albicans was evaluated using the agar diffusion method , in which the CDPs were placed on BHI plates inoculated with C. albicans with measuring the zone of inhibition after 48 hours incubation at 37 C. The analysis of the resins conversion degree is given by infrared spectroscopy Fourier transform - FTIR using an uncured resin sample in each group and 4 scans performed absorbance . For the measurement of resins containing CDA s water sorption, 10 specimens were prepared for each group , which were placed in support within desiccator 37 C to remove intrinsic ( m1 ) and then immersed moisture in 100 ml deionized water for 7 days at 37 C , and the water was changed daily. After this interval , the specimens were dried to obtain the new resins weight ( m2 ) . The masses obtained were included in the mathematical formula for the degree of sorption. After obtaining results, when compared the inhibition halo between the tested groups and the same brand , only the analyzes between group CDA2 % x CDA 1 % group and from CDA 1 % x CDA0.5 %,showed no significant differences . About the release of CDA , analysis of variance showed that two of the three factors assessed ( drug concentration and storage time ) significantly change the rate of release of chlorhexidine ( p < 0.0001 ) , however the material mark seemed not significantly influence the drug release . About the conversion degree , the values were not significant and were minor only in groups with CDA 2 % . For both water sorption increased with the incorporation of salt grew and there was significant increase in concentrations of 1.0 % and 2.0 % . We conclude that the incorporation of chlorhexidine to the PMMA based resin : is able to inhibit the growth of C. Albicans ; did not alter the degree of conversion of the resins tested , does not alter the release of residual monomers , and changes the water sorption of the base PMMA acrylic resins when CDA concentrations are incorporated.

Resinas macias para reembasamento de próteses são largamente utilizadas após cirurgias para estabilizarem a prótese e condicionarem o tecido, aguardando a completa cicatrização. É importante que o material não seja facilmente colonizado por biofilme oral e se possível, evite a contaminação do sítio cirúrgico. Objetivou-se avaliar o efeito da incorporação de clorexidina às resinas acrílicas macias para o reembasamento de próteses totais, através de análises de liberação, citotoxicidade e efeito inibitório de um biofilme de C. albicans. Foram confeccionados corpos de provas (CDPs) com as resinas Trusoft e Coe-soft, com incorporação de 0%, 0,5%, 1,0% e 2,0% de clorexidina, totalizando 8 grupos. A liberação de clorexidina foi avaliada através da mensuração da mudança na densidade óptica da solução de armazenamento, na qual ficaram imersos os CDPs, por espectrometria UV, a cada 48 horas, durante 40 dias. A citotoxicidade celular foi avaliada em fibroblastos (linhagem L929), que ficaram 24 horas em contato com meio de cultura no qual os CDPs ficaram previamente imersos, pela técnica de absorção de corante vermelho neutro após 24, 48 e 72 horas e semanalmente até o 28 dia. E, por fim, a atividade antifúngica contra a C. albicans (ATCC 10231) foi avaliada de duas maneiras: (1) teste de difusão em ágar, no qual os CDPs foram colocados em placas de BHI previamente inoculadas com C. albicans, com medição do halo de inibição após 48 horas de incubação a 37C; (2) a avaliação da inibição da formação de um biofilme de C. albicans sobre a superfície dos CDPs pela quantificação por metil tetrazólio (MTT) a cada 48 horas, durante 22 dias, com leitura feita em espectrofotômetro de UV. Os dados obtidos foram inseridos no programa SigmaStat (versão 3.1, USA) para realizar as análises estatísticas. As diferenças estatísticas foram determinadas por análises de variâncias do tipo ANOVA e todos os procedimentos para comparações múltiplas pareadas foram feitos utilizando-se o método Holm-Sidak, com nível de significância global igual a 0,05. A clorexidina adicionada às resinas testadas foi capaz de ser liberada para o meio de armazenagem, proporcionalmente à quantidade de clorexidina incorporada, porém com diferentes cinéticas de liberação entre as resinas, visto que a Trusoft libera até 71% do total de clorexidina liberada nas primeiras 48 horas e a Coe-soft, até 44%. Ambas as resinas com incorporação de clorexidina apresentaram efeito citotóxico adicional, se comparadas às resinas sem clorexidina, porém para a Coe-soft não houve diferença estatística dos valores, apenas para a Trusoft (p<0,001). Ocorreu formação de halo de inibição proporcionalmente às concentrações de resinas adicionadas, com maiores halos para a resina Trusoft (p<0,001), e sem formação de halo para as resinas sem clorexidina; a inibição da formação de biofilme, realizada somente com a resina Coe-soft, mostrou total inibição durante 8, 12 e 16 dias, para a incorporação de 0,5%, 1,0% e 2,0% respectivamente, sendo uma diminuição estatisticamente significativa (p<0,001) em relação à resina sem incorporação de clorexidina, que não apresentou inibição do biofilme. / Denture soft lining materials are widely used after dental surgeries, tissue conditioning and stabilization of prostheses, until the complete tissue healing. It is important that this material not became easily colonized by oral biofilm and if possible, avoid contamination of the surgical site. The aim of this study was to evaluate the effect of chlorhexidine incorporation into resin-based soft denture lining material, considering the drug release analysis, cytotoxicity and C. albicans biofilm inhibition. Specimens were done using Trusoft and Coe-soft, incorporating 0%, 0.5%, 1.0% and 2.0% of chlorhexidine, totaling eight groups. The chlorhexidine release was evaluated through the measurement of change in optical density of the storage solution, which the specimens were immersed, by UV spectrometry, after every 48 hours for 40 days. The cellular cytotoxicity was evaluated in fibroblasts (strain L929), which were 24 hours in contact with culture medium, in which the specimens were previously immersed, the technique of neutral red dye uptake was used after 24, 48 and 72 hours and weekly until 28th day. Finally, the antifungal activity against C. albicans (ATCC 10231) was evaluated by two different ways: (1) agar diffusion test, in which the specimens were placed over the top of BHI agar plates previously inoculated with C. albicans, and the measurement of inhibition zone was done after 48h of incubation at 37C, (2) C. albicans biofilm inhibition over the specimens surface, which was mensured after every each 48 hours of biofilm and specimens co-incubation, by methyl tetrazolium (MTT), in UV/vis spectrophotometer, during 22 days. Data were analyzed with the SigmaStat software (version 3.1, USA). Statistical differences were determined by analysis of variance ANOVA and all procedures for multiple paired comparisons were made using the Holm-Sidak method, with overall significance level of 0.05. The chlorhexidine added to both resins, Trusoft and Coe-soft, can be released to the storage medium, with a dose-related effect, however the resins presented different release kinetics, since the Trusof released up to 71% of the total amount of the chlorhexidine released within the first 48 hours and Coe-soft release only up to 44%, considering the citotoxic effect, both chlorhexidine incorporated resins showed some extra cytotoxic effect, if compared to resins without chlorhexidine, but for Coe-soft no statistical difference of values was founded, only for Trusoft (p<0.001); considering the C. albicans inhibition, the agar diffusion test values were dose-related for both resins, however with bigger inhibition zones for Trusoft (p<0.001), and without any inhibition for the resins without clorexidine. For the C. albicans biofilm inhibition test, performed only with Coe-soft resin, it was verified a complete inhibition at 8, 12 and 16 days for the incorporation of 0.5%, 1.0% and 2.0% of clorexidine respectively, a statistically significant decrease (p<0.001) if compared to the resin without incorporation of chlorhexidine, which showed no inhibitory effect over the biofilm formation.

Indiana University-Purdue University Indianapolis (IUPUI) / Purpose: This in vitro study aims to analyze the effect of combining two ADA-recommended professionally applied 1:1 Chlorhexidine/Thymol varnish ((Cervitec Plus)) and professionally prescribed 5,000 ppm fluoride toothpaste ((PreviDent 5000 Plus)) on reducing lesion depth and increasing mineral content Materials & Methods: Forty-eight dentin specimens were randomly distributed into four treatment groups (n=12 per treatment). Biofilms of Streptococcus mutans and Candida albicans were created on the polished surfaces of bovine root dentin specimens (n=12 per treatment). 1:1 Chlorhexidine/Thymol varnish was applied once then the tested 5,000 ppm fluoride toothpaste was applied for 120 seconds twice daily over the course of 2 days. Tested groups were: (1) 1:1 Chlorhexidine/Thymol varnish ((Cervitec Plus)) (C/T). (2) 5,000 ppm F toothpaste ((PreviDent 5000 Plus)) (F). (3) Combination of 1:1 Chlorhexidine/Thymol varnish ((Cervitec Plus)) & 5000 ppm F toothpaste ((PreviDent 5000 Plus)) (C/T+F). (4) Deionized water (DIW) as control group. Biofilms were analyzed for biofilm dry weight. Dentin specimens were analyzed using transversal microradiography (TMR) for mineral content change and lesion depth. PH data was analyzed using two-way ANOVA. Total biofilm dry weight data was analyzed using one-way ANOVA. Integrated mineral loss and lesion depth data was analyzed using two-way ANOVA All pair-wise comparisons from ANOVA analysis were made using Fisher’s Protected Least Significant Differences to control the overall significance level at 5%. Results: Treatment with (C/T+F) resulted in higher mean pH values compared to the control group (DIW) and (F) group. The average pH values of group (C/T) were not statistically different than group (C/T+F). the biomass of the combined S. mutans & C. albicans biofilm among all the groups were not significantly different. (DIW) presented significantly deeper lesions for both surfaces (sound &demineralized) when compared to (F) (P=0.0118), (C/T) (P=0.0002), and (C/T+F) (P<.0001). The sound surfaces for the specimens for group (C/T) and Group (F) showed superficial lesion depth. However, the sound surfaces of specimens treated with (C/T+F) showed the most superficial depth. Due to mineral gain, the demineralized surfaces of the specimens of both (C/T) & (C/T+F) showed a decrease in the lesion depth. Conclusion: Within the limitations of our study. The combination of 5,000 ppm fluoride toothpaste and CHX/Thymol had no significant effect on mineral content. However, the combination had a considerable effect on lesion depth reduction.

Thesis (MCur)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Ventilator-Associated Pneumonia (VAP) is a hospital acquired infection, not present or incubating at the time of admission and developing in patients during the process of care within the hospital setting. Between nine and twenty-seven percent of patients who are mechanically ventilated will develop ventilator-associated pneumonia. Mortality rates for ventilated patients who develop ventilator-associated pneumonia are estimated to be between 33-50%. The Institute for Healthcare Improvements (IHI) in 2006 recommended the use of ‘care bundles’ to reduce VAP but no statistically significant decline has been noted. Despite the completion of an extensive literature search for purposes of this review, no statistical data on nosocomial infections or nosocomial pneumonia relevant to South Africa was found. Mechanical ventilation, a support therapy used in approximately one third of patients, significantly increases the patient’s risk of developing this nosocomial pneumonia. Critically ill patients are by virtue of their critical illness more prone to the development of infections, especially ventilator-associated pneumonia. Consistent evidence suggests that oropharyngeal colonization can be associated with the development of VAP. Studies focusing on standard oral care, with or without the concurrent use of chlorhexidine, have not provided sufficient evidence for the use of chlorhexidine in VAP prevention. Chlorhexidine is an antiseptic agent, which when tested, proved to reduce total respiratory tract infections by up to 69% (DeRiso et al, 1996:1558). Objective: The aim of this study was to systematically appraise and review evidence on the effectiveness of chlorhexidine in reducing the incidence of ventilator-associated pneumonia in adult patients. The secondary aim was to systematically summarize evidence on the use of chlorhexidine in reducing mortality. Methodology: An extensive literature search of studies published in English was undertaken. Electronic databases searched were CENTRAL, CINAHL, EMBASE and MEDLINE. Reference lists of articles, textbooks and conference summaries were examined. Literature searches were conducted using Medical Subject Headings (MeSH). These included: Ventilator-associated pneumonia, chlorhexidine, VAP and oral care. Eight randomized controlled trials, investigating the efficacy of Chlorhexidine in ventilator-associated pneumonia prevention in adults met the inclusion criteria. The effect measure of choice was Risk ratio with 95% confidence intervals for dichotomous data using the random effects (Mantel-Haenszel) model; (p=value of 0.05). Heterogeneity was assessed using the Cochrane Q statistic and I². Results: Eight randomized controlled trials met the inclusion criteria for this review. Pooled risk ratio for the incidence of ventilator-associated pneumonia was 0.64 (95% CI; 0.44-0.91; p =0.18). Treatment with chlorhexidine decreased the risk of ventilator-associated pneumonia by 36%. There was no evidence of Chlorhexidine reducing mortality. Conclusions: Chlorhexidine is a cost effective safe treatment in the prevention of VAP. The use of 2% chlorhexidine may be more effective in reducing the incidence of VAP. No studies were found conducted in developing countries. More rigorously designed trials using 2% chlorhexidine are recommended. / AFRIKAANSE OPSOMMING: Agtergrond Ventilator-Geassosieerde Longontsteking (VAP) is 'n hospitaal verkry infeksie, nie teenwoordig met toelating nie. Ventilator-geassosieerde longontsteking word ontwikkel in pasiënte tydens die proses van sorg in die hospitaal. Tussen nege en sewe en twintig persent van pasiënte wat meganies geventileer word kry ventilator-geassosieerde pneumonie. Sterftesyfers vir geventileerde pasiënte wat ventilator-geassosieerde pneumonie ontwikkel is na raming tussen 33- 50%. Die Institute for Healthcare Improvements (IHI) het in 2006 die gebruik van 'sorg bundels' aanbeveel om VAP te verminder, maar geen statisties beduidende daling is aangeteken nie. Ten spyte van 'n uitgebreide literatuur soek, is geen statistiese data op nosokomiale infeksies of nosokomiale longontsteking toepaslik tot Suid-Afrika gevind nie. Meganiese ventilasie, 'n ondersteuningsterapie wat gebruik word in ongeveer een derde van die pasiënte, verhoog aansienlik die pasiënt se risiko vir die ontwikkeling van hierdie nosokomiale longontsteking. Kritiek siek pasiënte is op gronde van hul kritieke toestand meer geneig tot die ontwikkeling van infeksies, veral ventilator-geassosieerde pneumonie. Konsekwente bewyse dui daarop dat orofaringeale kolonisasie kan met die ontwikkeling van VAP geassosieer word. Studies wat fokus op standaard mond sorg, met of sonder die gelyktydige gebruik van chlorhexidine, het nie voldoende bewyse vir die gebruik van chlorhexidine in VAP voorkoming nie. Chlorhexidine is 'n antiseptiese agent, wat wanneer in een verewekansigde gekontroleerde studies (VGS) getoets was die totale respiratoriese kanaal infeksies verminder deur tot 69%. Doel: Die doel van hierdie sistematiese literatuuroorsig was om stelselmatig te evalueer en bewyse oor die effektiwiteit van chlorhexidine in die vermindering en voorkoms van ventilatorgeassosieerde pneumonie in volwasse pasiënte te hersien. Die sekondêre doel was om stelselmatig bewyse op te som op die gebruik van chlorhexidine in die vermindering van sterfte. Metodiek: 'n Uitgebreide literatuursoektog van studies wat in Engels gepubliseer is was onderneem. CENTRAL, CINAHL, EMBASE en MEDLINE was deursoek. Naslaanlyste van artikels, handboeke en konferensie opsommings is ondersoek. Die literatuur soektog is uitgevoer met behulp van Medical Subject Headings (MeSH). Dit sluit in: ventilator-geassosieerde pneumonie, chlorhexidine, VAP en mond sorg. Agt verewekansigde gekontroleerde studies (VGS), wat die doeltreffendheid van Chlorhexidine in ventilator-geassosieerde pneumonie voorkoming in volwassenes ondersoek, was ingesluit vir hierdie studie. Die effek mate van keuse was risiko ratio (RR) met 95% vertrouensintervalle met behulp van die ewekansige effekte (Mantel-Haenszel) model; (p = 0.05). Heterogeniteit is bepaal deur gebruik te maak van die Cochrane Q- statistiek en I². Hoof resultate: Agt verewekansigde gekontroleerde studies (VGS) het die insluiting kriteria vir hierdie oorsig gepas. Gepoelde risiko ratio vir die voorkoms van ventilator-geassosieerde pneumonie: Risiko Ratio (RR) was 0.64 (95% CI; 0.44-0.91; p=0.18). Gevolgtrekkings: Behandeling met chlorhexidine het die risiko van ventilator-geassosieerde pneumonie met 36% gedaal. Daar was geen bewyse van Chlorhexidine op die vermindering van mortaliteit nie. Chlorhexidine is 'n koste-effektiewe veilige behandeling in die voorkoming van VAP. Die gebruik van 2% chlorhexidine kan moontlik meer effektief wees in die vermindering van die voorkoms van VAP. Meer streng ontwerp studies met 2% chlorhexidine word aanbeveel.

Background: Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus (MRSA) represent the most worrying Gram-negative and Gram-positive nosocomial pathogens of the present age. They are of increasing concern in the clinical environment due to their multi-drug resistance and the dwindling therapeutic options available. A. baumannii is the most frequently isolated clinical species of the genus, and is able to rapidly acquire resistance. Hypermutators, most frequently deficient in mismatch repair (MMR) via defects in the mutS gene, have been associated with antimicrobial resistance in several bacterial populations. To date, however, the potential role of MMR-deficient mutators in the development of resistance in clinical Acinetobacter spp. has not been investigated. Biocides, most notably chlorhexidine (CHX), are increasingly used in the hospital environment to prevent bacterial spread. This has led to concerns about the development of reduced biocide susceptibility and associated antibiotic resistance in hospital bacterial populations, where there is frequent exposure to both of these factors. The effect of CHX upon defined clinical MRSA isolates is examined here. Methods: The mutS gene of clinical Acinetobacter spp. isolates with varying sensitivities was sequenced and compared to establish whether any variations were present. Mutation studies were performed on isolates by challenging them with ciprofloxacin to determine whether different mutS types correlated with any variation in their ability to develop significant fluoroquinolone resistance. The response of clinical MRSA isolates to a range of CHX concentrations was examined with susceptibility testing methods, and effects were compared with standard strains. Determination of post-exposure minimum inhibitory concentrations (MICs) of a range of antibiotics enabled evaluation of whether exposure to CHX had an effect on susceptibility to antibiotics. Results: Variation was observed in the mutS gene of clinical Acinetobacter spp. isolates, with greater homology observed as resistance increased. A highly conserved and previously unreported amino acid sequence was discovered in resistant isolates. Nonresistant isolates with this ‘R-type’ mutS sequence appeared to have a greater ability to develop significant ciprofloxacin resistance. Clinical MRSA isolates had varying susceptibility to CHX, and there were differences in the susceptibility of standard strains compared to clinical isolates. CHX residues exerted a prolonged minimal inhibitory effect, and several increases in antibiotic MICs following CHX exposure were observed. Conclusions: The correlation of the mutS sequence with mutation ability suggests that defects in the mutS gene may have a role to play in the ability of certain Acinetobacter spp. to rapidly acquire resistance. This could have implications for the treatment of Acinetobacter spp. infections, and may enable quick determination of which clinical isolates have the potential to develop clinically significant resistance. Incomplete eradication due to the prolonged minimal effect of CHX residues may act as a selective pressure in the hospital environment, allowing survival of reduced susceptibility MRSA isolates. Increases in antibiotic MICs following CHX exposure is of grave concern for the future of biocide usage.