Influence of pre-irradiation time employed in antimicrobial photodynamic therapy with diode laser.

The aim of the present study was to evaluate, in vitro, the effect of different pre-irradiation times of the photosensitizer in photodynamic therapy in biofilms formed by Streptococcus mutans and Candida albicans, through the evaluation of the microbial load. The factors under study were as follows: times of pre-irradiation of the photosensitizer in three levels (1, 2, or 5 min). For the control of the cariogenic dental biofilm with antimicrobial photodynamic therapy (aPDT), methylene blue (0.01%) was used in association with the diode laser (InGaAlP) with a wavelength of 660 nm. Chlorhexidine digluconate (0.12% CHX) and saline were used as positive and negative controls, respectively. The study design was carried out in complete and randomized blocks. The sample consisted of 15 S. mutans biofilms cultures, randomly divided into five groups and 15 C. albicans cultures, also divided into five groups. The experiment was performed in triplicate (n = 3) and the response variables were obtained through quantitative analysis of bacterial viability, expressed in colony-forming units (CFU) per square millimeter of the specimen area. The data were analyzed with the aid of the ANOVA one-way test and Tukey's post-test. All analyses were performed using the Graph Pad Prism 4.0 program, with a significance level of 5%. For the S. mutans group, only the saline solution presented a statistically significant difference when compared to the other treatments (p < 0.05), that is, the treatment with aPDT, irrespective of the irradiation time applied, was similar to the treatment with CHX and both were more effective in reducing cariogenic biofilm compared to saline. For the group of C. albicans, there was no statistical difference between the groups (p > 0.05). Therefore, it can be concluded that the treatment with aPDT reduced the number of CFUs of S. mutans in a similar way to CHX, independently of the pre-irradiation time applied. No effect of this therapy or of the different pre-irradiation times on the C. albicans biofilm could be observed. In this way, the pre-irradiation time of 1 min can be used to reduce the microbial load of S. mutans.

Assessment of peripheral venous catheters microbiota and its association with phlebitis.

BACKGROUND: Peripheral venous catheters (PVCs) remain the primary mode of short-term venous access for managing intravenous fluid, obtaining blood samples, and peripheral parenteral nutrition. They may get contaminated and require regular monitoring to prevent complications. This study evaluated the occurrence of phlebitis and its associated-clinical and microbiological indicators. METHODS: The frequency of phlebitis was evaluated in hospitalized patients of both medical and surgical fields. Subsequently, the dichotomous association between the presence of phlebitis and the clinical aspects was investigated. In parallel, the bacterial contamination of PVCs was assessed through culture-based methods, microscopy observation, and 16S rRNA gene sequencing. RESULTS: Approximately one in four patients presented phlebitis (28.4%). The most frequent symptom was erythema at access site, with or without pain, corresponding to Score 1 on the phlebitis scale (17.9%). Colonization of both lumen and external surface of PVC was observed in 31.3% of the samples. Staphylococcus and Pseudomonas were the most isolated bacterial genera on the PVC surface. No significant association was observed between the presence of phlebitis and the clinical aspects, as well as the presence of microorganisms. CONCLUSION: Microorganism were present on both internal and external PVC surface, without being associated to phlebitis.

The long-term effect of sub-boiling water on dental unit waterlines and its ability to control cross-contamination in dentistry.

This study investigated the effect of water at high temperature on the physical and mechanical properties of polyurethane and on biofilm removal, aiming for its applicability in dental unit waterlines. The evaluations were carried out after simulating a 1-year period of daily immersion and measured changes in color, microhardness, surface roughness, and tensile strength before and after reproducing a disinfection protocol. For antibiofilm activity measurement, fragments of waterline were contaminated with Pseudomonas aeruginosa and submitted to the disinfection protocols. Relative to effects on the physical and mechanical properties, immersion in water at 60°C did not promote changes in color and tensile strength. However, lower values were observed for microhardness and increased values for surface roughness. Regarding antibiofilm action, water at 60°C significantly reduced the microbial load and promoted substantial changes in cells morphology. In conclusion, disinfection with water at 60°C demonstrated possible application in controlling cross-contamination in dentistry.

Biosafety of Non-Return Valves for Infusion Systems in Radiology.

Cross-infection in contrast injectors is still a subject under discussion with little understanding. This study evaluated the biosafety of non-return valves (NRVs). Initially, the maximum pressure during backflow of intact and disrupted flexible diaphragms (FDs) from NRVs, as well as the functionality of connectors with NRVs were verified. The performance of air columns interposed by water in connectors with NRVs was analyzed, and the diffusion distance of crystal violet through connectors with NRVs was measured. The efficacy of NRVs as a barrier to bacterial contamination from backflow was evaluated. Finally, a clinical study of bacteriological contamination from syringes was conducted. There were differences among the maximum tolerated pressure by intact and disrupted FDs. Disrupted FDs showed no failures in the functionality of connectors with NRVs based on the lack of air bubbles released. Air columns could move through connectors with NRVs with intact and disrupted FDs. The longest diffusion distance of crystal violet was 6 cm of connector length, and NRVs showed efficacy as a barrier to bacterial contamination. In the clinical study, there was no bacterial growth in any of the evaluated samples. In conclusion, biosafety depends on the functionality of NRVs as well as proper practical clinical performance.

Human teeth biobank: Microbiological analysis of the teeth storage solution.

The cross-infections may occur during handling of dental elements, affecting the health of dental practitioners and researchers. This study aimed to analyze the influence of the storage medium temperature on the bacterial contingent of the human teeth used for research purposes. Thirty human teeth were donated to the Human Teeth Biobank immediately after extraction. The teeth were cleaned with tap water and neutral soap. The teeth were randomly distributed according to the temperature of the storage solution (deionized water): at 4 °C (refrigerator) or at -10 °C (freezer) and were stored individually in sterile vials during 60 days. After this period, a microbiological analysis (CFU/mL) of the storage solutions was performed and teeth were submitted to SEM analysis. Data were analyzed by Kruskal-Wallis test followed by Dunn's post-test (p ≤ .05). Total aerobic bacteria ranged from 5.8 to 8.4 log10 CFU/mL for refrigerated solution and from 1.9 to 8.5 log10 CFU/mL for frozen solution. No statistical differences were found between the storage solutions (p > .05). The counts of Streptococcus spp., Lactobacillus spp., and Staphylococcus spp. were similar for both storage solutions (p > .05). SEM analysis showed spiral- and rod-shaped bacteria attached on teeth stored under 4 °C, which may suggest the presence of Treponema spp. and Lactobacillus spp. Similar morphological forms were found on teeth stored under -10 °C. A biofilm organized in honeycomb-like form was found in the frozen teeth. Cocci were eventually found in all the samples. It was concluded that bacterial growth and survival were not influenced by the temperature of the teeth storage solution.

Biofilms formation and prevention on urinary catheters: a bibliometric analysis / Formação e prevenção de biofilmes em cateteres urinários: uma análise bibliométrica

To map the scientific production about biofilms formation and prevention on urinary catheters. It is a bibliometric, exploratory, and descriptive research performed in Web of Science™, in three stages, and utilizing HistCite™ software. In this regard, descriptors "Biofilm*" AND "Urinary Catheter*" were utilized within the period between 1945 and 2016. A total of 329 articles about biofilm on urinary catheter were found from 1985 to 2016. These articles were written by 1,262 authors from 452 institutions located in 50 countries. The relation among the 15 selected articles, the most impacting ones, evidences the existence of experimental researches; most of them was in vitro. The control of biofilm formation on urinary catheters remains as a major challenge in the health area, because new ways are necessary to improve the prevention and minimization of this phenomenon.

Mapear a produção científica acerca da formação e prevenção de biofilmes em cateteres urinários. Trata-se de uma pesquisa bibliométrica, exploratória e descritiva, realizada no Web of Science™, em três estágios, e utilizando o software HistCite™. Nesse sentido, foram utilizados os descritores "Biofilme*" E "Cateter Urinário*" no período de 1945 a 2016. Foram encontrados 329 artigos sobre biofilme em cateter urinário no período de 1985 a 2016. Estes artigos foram escritos por 1.262 autores de 452 instituições localizadas em 50 países. A relação entre os 15 artigos selecionados, os mais impactantes, evidencia a existência de pesquisas experimentais; a maioria delas foi in vitro. O controle da formação de biofilme nos cateteres urinários permanece como um grande desafio na área da saúde, pois são necessárias novas formas de melhorar a prevenção e a minimização desse fenômeno.

Jalecos em têxteis de poliéster agem como barreira contra fluidos e bactérias? / ¿Batas médicas de telas de poliéster actúan como barrera contra fluidos y bacterias? / Do white coats on polyester fabrics act as a barrier against fluids and bacteria?

Resumo Objetivo Avaliar tecidos de poliéster quanto à função de barreira física contra fluidos e bactérias. Métodos Trata-se de uma pesquisa experimental laboratorial in vitro realizada em três etapas: avaliação do tempo de passagem de fluido através dos tecidos, cronometrado desde o início do escoamento do fluido até a formação e queda da última gota; determinação microbiológica da carga bacteriana presente no fluido, após a sua passagem através dos tecidos; e análise das características estruturais dos tecidos por meio de microscopia eletrônica de varredura. Os dados foram submetidos aos testes de normalidade e ao teste de U de Mann-Whitney, com nível de significância de a=5%. Resultados as comparações dos tempos obtidos na primeira etapa entre os dois tipos de tecidos utilizados demonstraram diferença estatística ( p <0,001). Com relação à avaliação microbiológica, não foi observada diferença entre as cargas bacterianas após a passagem do fluido através dos tecidos, tanto para Staphylococcus aureus ( p =0,056) quanto para Pseudomonas aeruginosa ( p= 0,320). A análise por microscopia eletrônica de varredura evidenciou diferenças estruturais entre os tecidos, no entanto não foi constatada a presença bacteriana na superfície dos tecidos. Conclusão Ambos os tecidos de poliéster empregados para confecção de jalecos não apresentaram função de barreira física contra fluidos e bactérias. Assim, os resultados nos permitem especular que o jaleco de poliéster ao entrar em contato com fluidos corporais pode possibilitar a contaminação do profissional.

Resumen Objetivo Evaluar telas de poliéster con relación a la función de barrera física contra fluidos y bacterias. Métodos Se trata de un estudio experimental de laboratorio in vitro realizado en tres etapas: evaluación del tiempo de pasaje del fluido a través de las telas, cronometrado desde el inicio del derrame del fluido hasta la formación y caída de la última gota; determinación microbiológica de la carga bacteriana presente en el fluido después del pasaje a través de las telas; y análisis de las características estructurales de las telas mediante microscopio electrónico de barrido. Con los datos obtenidos se realizaron las pruebas de normalidad y la prueba U de Mann-Whitney, con nivel de significación de a=5%. Resultados La comparación de los tiempos obtenidos en la primera etapa entre los dos tipos de telas utilizados demostró diferencia estadística ( p <0,001). Respecto a la evaluación microbiológica, no se observó diferencia entre las cargas bacterianas después del pasaje del fluido a través de las telas, tanto de Staphylococcus aureus ( p =0,056) como de Pseudomonas aeruginosa ( p= 0,320). El análisis mediante microscopio electrónico de barrido constató diferencias estructurales entre las telas; sin embargo, no se observó la presencia bacteriana en la superficie de las telas. Conclusión Las dos telas de poliéster empleadas para la confección de batas médicas no presentan función de barrera física contra fluidos y bacterias. De esta forma, los resultados nos permiten suponer que la bata médica de poliéster, al entrar en contacto con fluidos corporales, puede posibilitar la contaminación del profesional.

Abstract Objective To evaluate polyester fabrics as physical barrier function against fluids and bacteria. Methods This is an in vitro experimental laboratory research carried out in three stages: evaluation of the length of time for the fluid to pass through the fabrics, timed from the beginning of the fluid flow until the formation and fall of the last drop; microbiological determination of the bacterial load in the fluid, after its passage through the fabrics; and analysis of the structural characteristics of the fabrics by scanning in electron microscopy. The data were submitted to normality tests and the Mann-Whitney U test, with a significance level of a=5%. Results Comparisons of length of time in the first stage between the two types of fabrics used showed a statistical difference ( p <0.001). Regarding the microbiological evaluation, there was no difference among bacterial loads after the fluid passed through the fabrics, both for Staphylococcus aureus ( p =0.056) and Pseudomonas aeruginosa ( p =0.320). The analysis by scanning electron microscopy showed structural differences between the fabrics, however, there were no bacteria on the fabric surface. Conclusion Both polyester fabrics used to make white coats did not work as a physical barrier against fluids and bacteria. Thus, the results allowed us to speculate that the polyester coat when in contact with body fluids may allow contamination of the professional.

Cateter urinário: o tempo de exposição e calibre podem influenciar na formação de biofilme? / Catéter urinario: ¿el tiempo de exposición y calibre puede influir en la formación de biofilm? / Urinary catheter: can exposure time and gauge affect biofilm formation?

Resumo Objetivo: Avaliar a influência do tempo de exposição e calibre na formação de biofilme em cateteres urinários de Foley (CUFs). Método: Pesquisa in vitro com amostras de fragmentos de CUFs em látex siliconizado de diferentes calibres (n° 14 e n° 16 Frenchs). A urina artificial foi confeccionada, inoculada com bactérias-padrão Staphylococcus aureus (ATCC 25923) e Pseudomonas aeruginosa (ATCC 27853) e incubada a 37 °C por 24 horas e 72 horas. As análises foram realizadas por meio de cultura (carga bacteriana) e microscopia eletrônica de varredura. Resultados: Não houve diferença na carga bacteriana dos biofilmes formados nas superfícies dos CUFs com relação aos diferentes calibres (p > 0,05). Por outro lado, o tempo de exposição (24 horas e 72 horas) foi o fator determinante para formação do biofilme de P. aeruginosa nos CUFs (p < 0,05). Conclusão: O tempo de exposição influenciou a formação do biofilme de P. aeruginosa nos CUFs, independentemente dos calibres.

Resumen Objetivo: Evaluar la influencia del tiempo de exposición y calibre en la formación de biofilm en catéteres urinarios de Foley (CUFs). Método: Investigación in vitro con muestras de fragmentos de CUFs en látex siliconizado de diferentes calibres (n ° 14 y n° 16 Frenchs). La orina artificial fue confeccionada, inoculada con bacterias estándar Staphylococcus aureus (ATCC 25923) y Pseudomonas aeruginosa (ATCC 27853) e incubada a 37 °C durante 24 horas y 72 horas. Los análisis se realizaron por medio de cultivo (carga bacteriana) y microscopía electrónica de exploración. Resultados: No hubo diferencia en la carga bacteriana de los biofilmes formados en las superficies de los CUFs en relación con los diferentes calibres (p> 0,05). Por otro lado, el tiempo de exposición (24 horas y 72 horas) fue el factor determinante para la formación del biofilm de P. aeruginosa en los CUFs (p <0,05). Conclusión: El tiempo de exposición influenció la formación del biofilm de P. aeruginosa en los CUFs, independientemente de los calibres.

Abstract Objective: To assess the effects of exposure time and gauge of Foley catheters in biofilm formation. Method: In vitro study with samples of Foley catheter fragments made of siliconized latex of different gauges (#14 and #16 French gauge). Artificial urine was produced, which was inoculated with Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853) standard bacteria, incubated at 37 °C for 24 hours and 72 hours. The material was analyzed by means of culture (bacterial load) and scanning electron microscopy. Results: There was no difference in bacterial load of biofilms formed in Foley catheter surfaces with regard to different gauges (p > 0.05). On the other hand, exposure time (24 hours and 72 hours) was a determining factor for P. aeruginosa biofilm formation in Foley catheters (p < 0.05). Conclusion: Exposure time had an effect on P. aeruginosa biofilm formation in Foley catheters, regardless of gauges.

Prevenção da formação de biofilmes em marcapassos artificiais: é viável? / Prevention of biofilm formation on artificial pacemakers: is it feasible?

Resumo Objetivo: Identificar os agentes antimicrobianos utilizados na prevenção da formação de biofilme em marcapassos artificiais. Métodos: Revisão da literatura para responder a seguinte questão: "Quais agentes antimicrobianos são usados para prevenir a formação de biofilmes em marcapassos artificiais?" As bases de dados PubMed, Web of Science, Scopus, Science Direct, Cochrane, CINAHL, Embase e LILACS foram consultadas em todos os idiomas sem restrição de tempo. Resultados: A amostra final apresentou cinco estudos primários, sendo a maioria experimental. As investigações identificaram agentes com potencial para a redução ou inibição da formação de biofilmes em marcapassos. Destacou-se a associação de agentes físico-químicos e farmacológicos aos agentes antimicrobianos. Conclusão: A prevenção da formação de biofilmes em marcapassos é viável. Os agentes mais promissores para obter este efeito foram a rifampicina, AIGIS®, a formulação aquosa neobactrim e a cobertura com trimetilsilano e oxigênio em superfícies tratadas com plasma.

Abstract Objective: To identify the antimicrobial agents used in the prevention of biofilm formation on artificial pacemakers. Methods: Literature review, in order to answer the following question: "What antimicrobial agents are applied to prevent biofilm formation on artificial pacemakers?" The databases PubMed, Web of Science, Scopus, Science Direct, Cochrane, CINAHL, Embase, and LILACS were used in all languages and without time restriction. Results: The final sample consisted of five primary studies, mostly experimental laboratory ones. The investigations identified agents with promising potential for reduction or inhibition of biofilm formation on pacemakers. An association between physical-chemical agents and pharmacological antimicrobials was highlighted. Conclusion: Prevention of biofilm formation on pacemakers is feasible. Among the agents that stood out were rifampicin, AIGIS®, aqueous neobactrim formulation, and a plasma coating using a combination of trimethylsilane and oxygen for coating deposition.

Protocolo com produtos químicos para o enfrentamento do biofilme em linhas d'água de equipos odontológicos: perspectiva física, química, mecânica e biológica / Protocol with chemical products to combat biofilm on dental unit waterlines: physical, chemical, mechanical, and microbiological perspective

A biossegurança na odontologia visa o enfrentamento da contaminação cruzada e o biofilme em linhas d'água de equipos odontológicos. O objetivo deste estudo foi investigar, na perspectiva física, química, mecânica e biológica, um protocolo de uso de produtos químicos com possível aplicabilidade nas linhas d'água de equipos odontológicos para melhoria e manutenção da qualidade da água. O protocolo com produtos químicos (Produto A - ácido cítrico + cloreto de sódio; Produto B - bicarbonato de sódio + cloreto de sódio; Produto AB - ácido cítrico + bicarbonato de sódio + cloreto de sódio) foi empregado em corpos de prova de aço inoxidável que, posteriormente, foram submetidos aos ensaios de microdureza e corrosão. Ainda, ensaios de cor, microdureza, rugosidade e de atividade antibiofilme [biomassa total (cristal violeta), atividade metabólica (XTT), viabilidade por meio de corante fluorescente e microscopia confocal de varredura à laser, bem como morfologia estrutural do biofilme por microscopia eletrônica de varredura (MEV)] foram realizados em corpos de prova de poliuretana. As cepas padrão empregadas para avaliar a atividade antibiofilme monoespécie foram Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 29923) e Escherichia coli (ATCC 25922). Com relação à alteração da microdureza no aço inoxidável, após a imersão simulada por 1 e 2 anos nos Produtos (A+B+AB), não houve diferença dos resultados com o grupo controle (água). Decorrida a exposição aos produtos e grupo controle, a maioria das amostras de aço inoxidável apresentou tendência à corrosão. Ainda, houve alterações de cor, microdureza e rugosidade nas superfícies de poliuretana após a imersão simulada por 1 e 2 anos dos produtos e do grupo controle. A avaliação da biomassa dos biofilmes indicou que o Produto A (p=0,003) e o Produto AB (p=0,019) reduziram significativamente o biofilme de P. aeruginosa em comparação com o controle. Por outro lado, a avaliação da biomassa do biofilme formado por S. aureus sugeriu que o Produto B (p=0,018) promoveu maior ação antibiofilme. Em relação aos biofilmes formados por E. coli, o Produto A (p=0,001) e o uso sequencial dos Produtos A+B+AB (p=0,021) mostraram os melhores resultados. Para o XTT em comparação com o controle, os tratamentos com o Produto A (p=0,001), o Produto AB (p<0,001) e o uso sequencial dos Produtos A+B+AB (p=0,002) reduziram significativamente a atividade metabólica do biofilme de P. aeruginosa. No biofilme formado por S. aureus, contrariando os resultados observados na avaliação da biomassa, o Produto B não promoveu alterações significantes na atividade metabólica (Produto A: p<0,001; Produto AB: p=0,007; uso sequencial dos Produtos A+B+AB: p<0,001). Considerando o biofilme formado por E. coli, observou-se que o Produto B (p=0,046), o Produto AB (p<0,001) e o uso sequencial dos Produtos A+B+AB (p<0,001) promoveram redução da atividade metabólica. Observou-se redução significativa do biofilme total após o emprego dos produtos (p<0,001), em relação ao controle. Apesar da redução significativa, ainda se observou agregados de biofilme residual, cobrindo extensa porção das superfícies, mesmo após o uso dos produtos. Considerando a quantidade de células vivas de P. aeruginosa e E. coli, o Produto A e o Produto B, isolados ou em conjunto demostraram resultados semelhantes. Além disso, o Produto AB e o uso sequencial dos Produtos A+B+AB não promoveu diferença na quantidade de células vivas de S. aureus, em comparação ao controle, indicando que a combinação dos produtos não potencializou a atividade antibiofilme. Em conclusão, os produtos analisados nesta pesquisa mostraram potencial inovador para o enfrentamento do biofilme linha d'água dos equipos odontológicos, preservando as propriedades físicas, químicas e mecânicas dos materiais.

Biosafety in dentistry aims to combat cross-contamination and biofilm on dental unit waterlines. The aim of this study was to investigate, from a physical, chemical, mechanical, and biological perspective, a protocol for the use of chemical products with possible applicability in dental unit waterlines to improve and maintain water quality. The protocol with chemicals (Product A - citric acid + sodium chloride; Product B - sodium bicarbonate + sodium chloride; Product AB - citric acid + sodium bicarbonate + sodium chloride) was used in stainless steel specimens which, later, were subjected to microhardness and corrosion tests. Moreover, color, microhardness, roughness and antibiofilm activity tests [total biomass (crystal violet), metabolic activity (XTT), viability by means of fluorescent dye and confocal laser scanning microscopy, as well as structural morphology of biofilm by scanning electron microscopy (SEM)] were performed on polyurethane specimens. The standard strains used to assess monospecies antibiofilm activity were Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 29923) and Escherichia coli (ATCC 25922). Regarding the microhardness change in stainless-steel, after simulated immersion for 1 and 2 years in Products (A+B+AB), there was no difference in the results with the control group (water). After exposure to the products and control group, most stainless-steel samples showed a tendency to corrosion. Furthermore, there were changes in color, microhardness, and roughness on the polyurethane surfaces after simulated immersion for 1 and 2 years of the products and the control group. Biofilm biomass evaluation indicated that Product A (p=0.003) and Product AB (p=0.019) significantly reduced P. aeruginosa biofilm compared to the control. On the other hand, the evaluation of the biomass of the biofilm formed by S. aureus suggested that Product B (p=0.018) promoted greater antibiofilm action. Regarding biofilms formed by E. coli, Product A (p=0.001) and the sequential use of Products A+B+AB (p=0.021) showed the best results. For XTT compared to the control, treatments with Product A (p=0.001), Product AB (p<0.001) and sequential use of Products A+B+AB (p=0.002) significantly reduced metabolic activity from the biofilm of P. aeruginosa. In the biofilm formed by S. aureus, contrary to the results observed in the biomass assessment, Product B did not promote significant changes in metabolic activity (Product A: p<0.001; Product AB: p=0.007; sequential use of Products A+B+ AB: p<0.001). Considering the biofilm formed by E. coli, it was observed that Product B (p=0.046), Product AB (p<0.001) and the sequential use of Products A+B+AB (p<0.001) promoted a metabolic activity reduction. There was a significant reduction in the total biofilm after using the products (p<0.001), compared to the control. Despite the significant reduction, residual biofilm aggregates were still observed, covering a large portion of the surfaces, even after using the products. Considering the amount of living cells of P. aeruginosa and E. coli, Product A and Product B, alone or together, showed similar results. In addition, Product AB and the sequential use of Products A+B+AB did not promote difference in the amount of living S. aureus cells, compared to the control, indicating that the combination of products did not enhance the antibiofilm activity. In conclusion, the products analyzed in this research showed innovative potential for facing the biofilm on dental unit waterline, preserving the physical, chemical, and mechanical properties of the materials.

Qualidade da água em clínica odontológica na perspectiva microbiológica: uma proposta de intervenção / Water quality in a dental clinic in the microbiological perspective: a proposal of intervention

Na odontologia, o biofilme formado nas linhas d'água de equipos odontológicos pode disseminar a contaminação microbiana na água. O objetivo desta pesquisa foi investigar a contaminação microbiana da água de abastecimento e de equipos odontológicos antes e após a implementação de um protocolo para melhoria e manutenção da qualidade microbiológica da água de equipos odontológicos, bem como desenvolver produtos antibiofilme com possível aplicabilidade nas linhas d'água. A carga microbiana da água de 27 torneiras e equipos (reservatórios, seringas tríplice e alta rotação) de uma clínica odontológica foi avaliada por meio do sistema Petrifilm(TM) (bactérias aeróbias totais e fungos) e meios de cultura convencionais (enterobactérias e Legionella spp.) em duas etapas distintas, sendo a segunda análise realizada após a implementação de um protocolo para melhoria e manutenção da qualidade microbiológica da água dos equipos. Ainda, as atividades antibacteriana (concentração inibitória mínima - hipoclorito de sódio, ácido cítrico, bicarbonato de sódio, cloreto de sódio, dodecil sulfato de sódio, peróxido de hidrogênio, polissorbato 20 e quitosana) e antibiofilme (biomassa total e viabilidade celular) foram determinadas in vitro a partir de substâncias e produtos com possível aplicabilidade na desinfecção de linhas d'água de equipos. As amostras de água das torneiras apresentaram carga bacteriana dentro do parâmetro estabelecido pela legislação brasileira, no entanto, as seringas tríplices e os alta rotação não. A implementação do protocolo para manutenção da qualidade microbiológica da água dos equipos demonstrou uma redução nas cargas bacteriana e fúngica apenas nos alta rotação. Enterobactérias e Legionella spp. não foram isoladas das amostras de água das torneiras e dos equipos. De acordo com a concentração inibitória mínima, o ácido cítrico, bicarbonato de sódio, cloreto de sódio, hipoclorito de sódio e peróxido de hidrogênio demonstraram as melhores atividades antibacterianas. As melhores atividades antibiofilme (biomassa total) foram do peróxido de hidrogênio a 5% (E. coli e P. aeruginosa), ácido cítrico a 30% (P. aeruginosa) e bicarbonato de sódio a 30% (S. aureus). Os produtos (Wanitox A e Wanitox B) desenvolvidos apresentaram atividade antibiofilme (viabilidade celular) contra a E. coli e S. aureus. Assim, os produtos desenvolvidos nesta pesquisa apresentaram possível aplicabilidade no enfrentamento do biofilme nas linhas d'água de equipos odontológicos, que permanece como um dos grandes desafios na odontologia. Ainda, pesquisas adicionais são necessárias para o aperfeiçoamento e aplicabilidade destes produtos

In dentistry, biofilm formed on dental unit waterlines can disseminate microbial contamination in water. The objective of this research was to determine the microbial contamination of water from supplies and dental units before and after the implementation of a protocol for improvement and maintenance of microbiological water quality of water from dental units as well as to develop antibiofilm products with possible applicability in waterlines. The microbial load of water from 27 taps and dental units (reservoirs, air-water syringes and high-speed turbines) in a dental clinic was evaluated through a Petrifilm(TM) system (total aerobic bacteria and fungi) and conventional culture mediums (enterobacteria and Legionella spp.) in two distinct stages, being the second analysis performed after the implementation of a protocol for improvement and maintenance of microbiological water quality of water from dental units. Moreover, the antibacterial (minimum inhibitory concentration - sodium hypochlorite, citric acid, sodium bicarbonate, sodium chloride, sodium dodecyl sulfate, hydrogen peroxide, polysorbate 20 and chitosan) and antibiofilm (total biomass and cell viability) activities were determined in vitro from substances and products with possible applicability in disinfection of dental unit waterlines. The water samples from taps presented bacterial load within the parameter established by Brazilian legislation; however, air-water syringes and high-speed turbines did not. The protocol implementation for maintenance of microbiological water quality of water from dental units showed a decrease on bacterial and fungal loads only on high-speed turbines. Enterobacteria and Legionella spp. were not isolated from water samples from taps and dental units. According to minimum inhibitory concentration, citric acid, sodium bicarbonate, sodium chloride, sodium hypochlorite and hydrogen peroxide showed the best antibacterial activities. The best antibiofilm activities (total biomass) were from 5% hydrogen peroxide (E. coli and P. aeruginosa), 30% citric acid (P. aeruginosa) and 30% sodium bicarbonate (S. aureus). The developed products (Wanitox A and Wanitox B) showed antibiofilm activity (cell viability) against E. coli and S. aureus. Thus, the products developed in this research presented a possible applicability in confrontation with biofilm on dental unit waterlines, and this remains as a major challenge in dentistry. Besides, additional researches are necessary for enhancement and applicability of these products