Effects of natural products-based dentifrices on acrylic resin for denture bases: A simulated period of 4 years.

PURPOSE: To evaluate the antimicrobial activity of dentifrices based on Malva sylvestris and propolis and the effect on the acrylic resin. METHODS: The inhibitory effect against Candida albicans, Enterococcus faecalis and Streptococcus mutans was determined. The specimens of resin were divided into groups: Control (brushing with distilled water); brushing with Colgate; brushing with Protex; brushing with Malvatricin, brushing with Proporalcare Dental Gel and brushing with Green Propolis Dental Gel. Brushing was carried out in a brushing machine. Roughness and color were assessed. The data were analyzed by ANOVA, followed by the Bonferroni post test (α= 0.05). RESULTS: The products evaluated showed antimicrobial activity against all microorganisms (P< 0.05), except Proporalcare Dental Gel, which was not effective against E. faecalis. Greater roughness (P< 0.05) was observed in the samples treated with Colgate. The samples from control and Protex groups showed the lowest color variation and the highest luminosity, with a difference in relation to the others (P< 0.05), which showed higher values, although clinically acceptable. CLINICAL SIGNIFICANCE: The dentifrices based on natural products can be indicated for cleaning prostheses, since they showed antimicrobial activity and did not cause perceptible color changes of the resin tested. The dentifrices did not produce adverse effects on the surface of the resin or did so less than the conventional dentifrice.

Unveiling the efficacy of latex gloves in preventing viral infections during needlestick injuries: An in vitro mixed-methods study.

BACKGROUND: Gloves are personal protective equipment designed to prevent contamination and reduce the spread of microorganisms. This study aimed to assess in vitro the physical integrity of latex gloves and the retention of biological contamination in healthcare simulation. METHOD: Three different batches of latex procedure gloves from five different brands and specific batches were evaluated before use for physical integrity by the standard protocols of the Society for Testing and Materials (ASTM) and of the American Food and Drug Administration (FDA). Moreover, the retention of biological contamination by latex procedure gloves in needlestick injury simulation with crystal violet and bacteriophages were applied in order to mimic human blood and virus presence. RESULTS: Brands D and C showed the best and worst results in the immediate inspections and after 2 min, respectively. For Brand C, damage occurred in one finger/region in a total of 12 gloves, while seven gloves were damaged/unable to be worn. Brand D presented only two gloves with tears and/or holes in one finger/region. Regarding the viral contamination, in a simulated needlestick injury, data showed no significant difference among the groups. CONCLUSION: All glove brands presented physical damage that might affect the spread of microorganisms. The gloves did not exert an additional protective effect during a needlestick injury simulation in accordance with the two techniques used in this study.

Effectiveness of experimental dentifrices based on essential oils on biofilm on complete dentures: an in vitro study.

Specific products containing natural resources can contribute to the innovation of complete denture hygiene. OBJECTIVE: To conduct an in vitro evaluation of experimental dentifrices containing essential oils of Bowdichia virgilioides Kunth (BvK), Copaifera officinalis (Co), Eucalyptus citriodora (Ec), Melaleuca alternifolia (Ma) and Pinus strobus (Ps) at 1%. METHODOLOGY: The variables evaluated were organoleptic and physicochemical characteristics, abrasiveness (mechanical brushing machine) simulating 2.5 years, and microbial load (Colony Forming Units - CFU/mL), metabolic activity (XTT assay) and cell viability (Live/Dead® BacLight™ kit) of the multispecies biofilm (Streptococcus mutans: Sm, Staphylococcus aureus: Sa, Candida albicans: Ca and Candida glabrata: Cg). Specimens of heat-polymerized acrylic resins (n=256) (n=96 specimens for abrasiveness, n=72 for microbial load count, n=72 for biofilm metabolic activity, n=16 for cell viability and total biofilm quantification) with formed biofilm were divided into eight groups for manual brushing (20 seconds) with a dental brush and distilled water (NC: negative control), Trihydral (PC: positive control), placebo (Pl), BvK, Co, Ec, Ma or Ps. After brushing, the specimens were washed with PBS and immersed in Letheen Broth medium, and the suspension was sown in solid specific medium. The organoleptic characteristics were presented by descriptive analysis. The values of density, pH, consistency and viscosity were presented in a table. The data were analyzed with the Wald test in a generalized linear model, followed by the Kruskal-Wallis test, Dunn's test (mass change) and the Bonferroni test (UFC and XTT). The Wald test in Generalized Estimating Equations and the Bonferroni test were used to analyze cell viability. RESULTS: All dentifrices showed stable organoleptic characteristics and adequate physicochemical properties. CN, Ec, Ps, Pl and PC showed low abrasiveness. There was a significant difference between the groups (p<0.001) for microbial load, metabolic activity and biofilm viability. CONCLUSIONS: It was concluded that the BvK, Ec and Ps dentifrices are useful for cleaning complete dentures, as they have antimicrobial activity against biofilm. The dentifrices containing Bowdichia virgilioides Kunth showed medium abrasiveness and should be used with caution.

Strategies for Preventing and Treating Oral Mucosal Infections Associated with Removable Dentures: A Scoping Review.

Oral infections occur due to contact between biofilm rich in Candida albicans formed on the inner surface of complete dentures and the mucosa. This study investigated historical advances in the prevention and treatment of oral mucosal infection and identified gaps in the literature. Bibliographic research was conducted, looking at PubMed, Embase, Web of Science, and Scopus, where 935 articles were found. After removing duplicates and excluding articles by reading the title and abstract, 131 articles were selected for full reading and 104 articles were included. Another 38 articles were added from the gray literature. This review followed the PRISMA-ScR guidelines. The historical period described ranges from 1969 to 2023, in which, during the 21st century, in vitro and in vivo studies became more common and, from 2010 to 2023, the number of randomized controlled trials increased. Among the various approaches tested are the incorporation of antimicrobial products into prosthetic materials, the improvement of oral and denture hygiene protocols, the development of synthetic and natural products for the chemical control of microorganisms, and intervention with local or systemic antimicrobial agents. Studies report good results with brushing combined with sodium hypochlorite, and new disinfectant solutions and products incorporated into prosthetic materials are promising.

Relation between the risk factors for the severity of denture stomatitis and quality of life of complete edentulous individuals: a cross-sectional study.

OBJECTIVE: To assess the association between risk factors for developing denture stomatitis (DS) and oral health-related quality of life (OHRQoL) in complete denture wearers. METHODOLOGY: Participants of both sexes, wearing complete dentures, were classified using the modified Newton classification for the absence or the severity of DS and allocated to groups Normal or zero, IA, IB, II, and III. Lifestyle, oral and denture history, and medication use were assessed using specific questionnaires; clinical parameters such as anatomical characteristics of support were evaluated with the Kapur classification; salivary flow (SF) was calculated by the volume of unstimulated saliva per minute; and microbial load was determined by counting colony forming units (CFU) of target microorganisms present in the biofilm collected from dentures and palate. OHIP-EDENT assessed the OHRQoL. Kendall's tau_b and Spearman tests were applied with a significance level of 5%. RESULTS: 184 patients (143 female and 41 male) aged 65.5 ± 6.8 years were evaluated. Positive correlations were found for sex (women; p=0.013, r=0.16), individuals who started to consume alcoholic beverages as a young adult (18-27 years) (p=0.008, r=0.22), CFU of Candida spp. (p<0.001, r=0.27 denture; p<0.001, r=0.31 palate); Candida albicans (p=0.004, r=0.22 denture; p=0.003, r=0.25 palate), and Candida glabrata (p=0.004, r=0.22 denture; p=0.001, r=0.27 palate). Moreover, negative correlations with DS were found for CFU of Staphylococcus spp. (p=0.004, r=-0.20 palate) and enterobacteria (p=0.002, r=-0.24 palate), as well as a negative correlation between SF (p=0.009, r=-0.193) and DS. The CFU of Staphylococcus spp. and enterobacteria on the palate significantly correlated with OHRQoL. CONCLUSION: Being female, consuming alcoholic beverages as a young adult, CFU of Candida spp., Candida albicans, Candida glabrata, and salivary flow may be the most significant risk factors for DS. The microbial load of Staphylococcus spp. and enterobacteria seems to influence the quality of life for complete denture wearers.

Effectiveness of experimental dentifrices based on essential oils on biofilm on complete dentures: an in vitro study

Abstract Specific products containing natural resources can contribute to the innovation of complete denture hygiene. Objective: To conduct an in vitro evaluation of experimental dentifrices containing essential oils of Bowdichia virgilioides Kunth (BvK), Copaifera officinalis (Co), Eucalyptus citriodora (Ec), Melaleuca alternifolia (Ma) and Pinus strobus (Ps) at 1%. Methodology: The variables evaluated were organoleptic and physicochemical characteristics, abrasiveness (mechanical brushing machine) simulating 2.5 years, and microbial load (Colony Forming Units - CFU/mL), metabolic activity (XTT assay) and cell viability (Live/Dead® BacLight™ kit) of the multispecies biofilm (Streptococcus mutans: Sm, Staphylococcus aureus: Sa, Candida albicans: Ca and Candida glabrata: Cg). Specimens of heat-polymerized acrylic resins (n=256) (n=96 specimens for abrasiveness, n=72 for microbial load count, n=72 for biofilm metabolic activity, n=16 for cell viability and total biofilm quantification) with formed biofilm were divided into eight groups for manual brushing (20 seconds) with a dental brush and distilled water (NC: negative control), Trihydral (PC: positive control), placebo (Pl), BvK, Co, Ec, Ma or Ps. After brushing, the specimens were washed with PBS and immersed in Letheen Broth medium, and the suspension was sown in solid specific medium. The organoleptic characteristics were presented by descriptive analysis. The values of density, pH, consistency and viscosity were presented in a table. The data were analyzed with the Wald test in a generalized linear model, followed by the Kruskal-Wallis test, Dunn's test (mass change) and the Bonferroni test (UFC and XTT). The Wald test in Generalized Estimating Equations and the Bonferroni test were used to analyze cell viability. Results: All dentifrices showed stable organoleptic characteristics and adequate physicochemical properties. CN, Ec, Ps, Pl and PC showed low abrasiveness. There was a significant difference between the groups (p<0.001) for microbial load, metabolic activity and biofilm viability. Conclusions: It was concluded that the BvK, Ec and Ps dentifrices are useful for cleaning complete dentures, as they have antimicrobial activity against biofilm. The dentifrices containing Bowdichia virgilioides Kunth showed medium abrasiveness and should be used with caution.

Relation between the risk factors for the severity of denture stomatitis and quality of life of complete edentulous individuals: a cross-sectional study

Abstract Objective To assess the association between risk factors for developing denture stomatitis (DS) and oral health-related quality of life (OHRQoL) in complete denture wearers. Methodology Participants of both sexes, wearing complete dentures, were classified using the modified Newton classification for the absence or the severity of DS and allocated to groups Normal or zero, IA, IB, II, and III. Lifestyle, oral and denture history, and medication use were assessed using specific questionnaires; clinical parameters such as anatomical characteristics of support were evaluated with the Kapur classification; salivary flow (SF) was calculated by the volume of unstimulated saliva per minute; and microbial load was determined by counting colony forming units (CFU) of target microorganisms present in the biofilm collected from dentures and palate. OHIP-EDENT assessed the OHRQoL. Kendall's tau_b and Spearman tests were applied with a significance level of 5%. Results 184 patients (143 female and 41 male) aged 65.5 ± 6.8 years were evaluated. Positive correlations were found for sex (women; p=0.013, r=0.16), individuals who started to consume alcoholic beverages as a young adult (18-27 years) (p=0.008, r=0.22), CFU of Candida spp. (p<0.001, r=0.27 denture; p<0.001, r=0.31 palate); Candida albicans (p=0.004, r=0.22 denture; p=0.003, r=0.25 palate), and Candida glabrata (p=0.004, r=0.22 denture; p=0.001, r=0.27 palate). Moreover, negative correlations with DS were found for CFU of Staphylococcus spp. (p=0.004, r=-0.20 palate) and enterobacteria (p=0.002, r=-0.24 palate), as well as a negative correlation between SF (p=0.009, r=-0.193) and DS. The CFU of Staphylococcus spp. and enterobacteria on the palate significantly correlated with OHRQoL. Conclusion Being female, consuming alcoholic beverages as a young adult, CFU of Candida spp., Candida albicans, Candida glabrata, and salivary flow may be the most significant risk factors for DS. The microbial load of Staphylococcus spp. and enterobacteria seems to influence the quality of life for complete denture wearers.

Action of disinfectant solutions on adaptive capacity and virulence factors of the Candida spp. biofilms formed on acrylic resin

Abstract Understanding the behavior of Candida spp. when exposed to denture disinfectants is essential to optimize their effectiveness. Changes in the virulence factors may cause increased resistance of Candida spp. to disinfectant agents. Objective To evaluate the microbial load, cellular metabolism, hydrolytic enzyme production, hyphae formation, live cell and biofilm quantification of Candida albicans, Candida tropicalis and Candida glabrata after exposure to disinfectant solutions. Methodology Simple biofilms were grown on heat-polymerized acrylic resin specimens, and divided into groups according to solutions/strains: distilled water (control); 0.25% sodium hypochlorite (NaOCl 0.25% ); 10% Ricinus communis (RC 10%); and 0.5% Chloramine T (CT 0.5%). The virulence factors were evaluated using the CFU count (microbial load), XTT method (cell metabolism), epifluorescence microscopy (biofilm removal and live or dead cells adhered), protease and phospholipase production and hyphae formation. Data were analyzed (α=0.05) by one-way ANOVA/ Tukey post hoc test, Kruskal-Wallis test and Wilcoxon test. Results NaOCl 0.25% was the most effective solution. CT 0.5% reduced the number of CFUs more than RC 10% and the control. RC 10% was effective only against C. glabrata. RC 10% and CT 0.5% decreased the cellular metabolism of C. albicans and C. glabrata. Enzyme production was not affected. Hyphal growth in the RC 10% and CT 0.5% groups was similar to that of the control. CT 0.5% was better than RC 10% against C. albicans and C. tropicalis when measuring the total amount of biofilm and number of living cells. For C. glabrata, CT 0.5% was equal to RC 10% in the maintenance of living cells; RC 10% was superior for biofilm removal. Conclusions The CT 0.5% achieved better results than those of Ricinus communis at 10%, favoring the creation of specific products for dentures. Adjustments in the formulations of RC 10% are necessary due to efficacy against C. glabrata. The NaOCl 0.25% is the most effective and could be suitable for use as a positive control.

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.

Evaluation of a protocol for reducing the microbial contamination of dental unit water

Biofilm on dental unit waterlines can spread microbial contamination in the water. The aim of this study was to investigate microbial contamination of water from supplies and dental units before and after the implementation of a protocol for microbial quality improvement and maintenance of dental unit water. The microbial load was evaluated in water from 27 taps and dental units (reservoirs, airwater syringes and highspeed outputs without handpieces) using the Petrifilm™ system (total aerobic bacteria and fungi) and conventional culture media (enterobacteria and Legionella spp.). The bacterial load in water samples from taps and reservoirs was within the parameter established by Brazilian legislation (<500CFU/mL); but the bacterial load in samples from airwater syringes and highspeed outputs without handpieces was not. The imple mentation of the protocol for the maintenance of microbial quality in dental unit water reduced bacterial load in highspeed outputs without handpieces (p=0.004). Enterobacteria and Legionella spp. were not isolated from any of the water samples from taps and dental units (AU)

Biofilme nas linhas d'água de equipos odontológicos pode propagar contaminação microbiana na água. O objetivo deste estudo foi investigar a contaminação microbiana da água de abastecimentos e equipos odontológicos antes e após a implemen tação de um protocolo para melhoria e manutenção da qualidade microbiológica da água de equipos odontológicos. Avaliouse a carga microbiana da água de 27 torneiras e equipos (reservatórios, seringas tríplice e alta rotação sem as peças de mão) de uma clínica odontológica por meio do sistema Petrifilm™ (bactérias aeróbias totais e fungos) e meios de cultura convencionais (enterobactérias e Legionella spp.). A carga bacteriana em amostras de água das torneiras e reservatórios estava dentro do parâmetro estabelecido pela legislação brasileira (<500 UFC/mL), mas a carga bacte riana das seringas tríplices e das saídas dos alta rotação sem as peças de mão não estava. A implementação do protocolo para manutenção da qualidade da água dos equipos reduziu a carga bacteriana nas saídas dos alta rotação sem as peças de mão (p=0,004). Enterobactérias e Legionella spp. não foram isoladas de qualquer das amostras de água das torneiras e dos equipos odontológicos (AU)

Hip prosthesis biomaterials: a challenge in prevention of biofilm formation / Biomateriais de próteses de quadril: um desafio na prevenção da formação de biofilme

The objective of this study was to identify the scientific evidences regarding biofilm formation prevention on hip prosthesis biomaterials. It's an integrative review that aims to answer the following question: what are the scientific evidences regarding biofilm formation prevention on hip prosthesis biomaterials? The search was performed on PubMed portal and on databases: Web of Science, Embase, Cochrane, CINAHL and LILACS. Primary studies about the topic published online up until November 2017 in English, Spanish and Portuguese are included. Among 16 primary studies, 81.25% were in vitro experimental studies, in which polyethylene showed a higher biofilm formation than metallic biomaterials and polymethylmethacrylate. Among clinical studies, Staphylococcus epidermidis and Staphylococcus aureus were isolated in most of joint prosthesis components. New acylase-containing polyurethane coatings, silver-zirconium carbonitride films, bioactive gentamicin, biodegradable gentamicin-hydroxyapatite, vancomycin, titanium-silicon-carbonoxygen-nitrogen films and cross-linked polyethylene combined with vitamin E and a poly(2-methacryloyloxyethyl phosphorylcholine) layer were developed to prevent biofilm formation. Moreover, cobalt-chromium (Co-Cr) ions inhibited bacterial growth, and cobalt-chromium particles reduced biofilm development. The biomaterials that presented properties against biofilm formation were: bioactive gentamicin, biodegradable gentamicin-hydroxyapatite, vancomycin, acylasecontaining polyurethane, cross-linked polyethylene combined with vitamin E-blended and a poly(2-methacryloyloxyethyl phosphorylcholine) layer, silver-zirconium carbonitride films and titanium-silicon-carbon-oxygen-nitrogen films. Moreover, the Co-Cr particles released from metallic joint prosthesis showed higher antibiofilm activity than Co-Cr ions.

O objetivo deste estudo foi identificar as evidências científicas a respeito da prevenção da formação de biofilme em biomateriais de próteses de quadril. Revisão integrativa da literatura, com vistas a responder a seguinte questão: quais são as evidências científicas a respeito da prevenção da formação de biofilme em biomateriais de próteses de quadril? Realizado no portal PubMed da National Library of Medicine e nas bases: Web of Science, Embase, Cochrane, CINAHL e LILACS. Incluíram-se estudos primários sobre a temática, publicados online até novembro de 2017 em inglês, espanhol e português. Dos 16 estudos primários analisados, 81,25% foram pesquisas experimentais in vitro; polietileno demonstrou maior contagem de unidades formadoras de colônia do que materiais metálicos e polimetilmetacrilato. Dos estudos clínicos, Staphylococcus epidermidis e Staphylococcus aureus foram isolados na maioria dos componentes das próteses articulares. Novos revestimentos constituídos de poliuretano contendo acilase, filmes de prata-carbonitreto de zircônio, gentamicina bioativa, gentamicina-hidroxiapatita biodegradável, vancomicina, filmes de titânio-silício-carbonooxigênio-nitrogênio e polietileno reticulado combinado com vitamina E e uma camada de poli (2-metacriloiloxietil fosforilcolina) foram desenvolvidos para prevenção da formação de biofilme. Além disso, íons de cobalto-cromo (Co-Cr) inibiram o crescimento bacteriano, e houve uma tendência das partículas de cobalto-cromo diminuírem o desenvolvimento de biofilmes. Os biomateriais que apresentaram propriedades que previnem a formação de biofilme foram: gentamicina bioativa, gentamicina-hidroxiapatita biodegradável, vancomicina, poliuretano contendo acilase, polietileno reticulado combinado com vitamina E e uma camada de poli (2-metacriloiloxietil fosforilcolina), filmes de prata-carbonitreto de zircônio e filmes de titânio-silício-carbono-oxigênio-nitrogênio. Além disso, partículas de Co-Cr liberadas das próteses articulares metálicas mostraram maior atividade antibiofilme que íons de Co-Cr.

Armazenar tubos de silicone antes do empacotamento impede a esterilização? / ¿Almacenar tubos de silicona antes del empaque impide la esterilización? / Does storage of silicone tubes prior to packaging prevent sterilization?

Resumo Objetivo: Determinar a carga microbiana de tubos de silicone imediatamente após a limpeza e em diferentes intervalos de armazenamento. Métodos: Estudo experimental que analisou tubos de silicone oriundos da assistência ao paciente cirúrgico. Foi conduzido após aprovação do Comitê de Ética (protocolo n° 1.277.077), no período de setembro a novembro de 2015, com tubos oriundos do Centro de Material e Esterilização (CME) de um hospital geral de grande porte da região Centro-Oeste do Brasil. Os tubos foram segmentados: extremidade 01, 02 e meio e novamente segmentados, conforme intervalos de tempo preestabelecidos em zero, 12 e 24 horas. Os fragmentos foram preenchidos com água estéril, vedados e submetidos a cinco minutos de sonicação. A água foi filtrada em Millipore 0,45 µm e as membranas incubadas a 35°C por 24 horas em ágar nutriente. As membranas foram removidas e dispostas em tubos de ensaio, contendo 1mL de solução salina, que foram agitadas por cinco minutos e submetidos a técnica de alça calibrada. Resultados: Houve aumento da carga microbiana na ordem de uma grandeza na escala logarítmica a cada 12 horas (p<0,05), nas condições de limpeza e armazenamento proporcionados pela instituição, nos grupos experimental e controle positivo, e não houve diferença quando comparados o meio e extremidades dos tubos de silicone (p>0,05) nos períodos zero, 12 e 24 horas. Conclusão: A depender da carga microbiana inicial, o aumento da ordem uma grandeza pode resultar no insucesso da esterilização, achados que ratificam a não permanência de PPS na área limpa aguardando o processamento.

Resumen Objetivo: Determinar la carga microbiana de tubos de silicona inmediatamente después de su limpieza e en diferentes intervalos de almacenamiento. Métodos: Estudio experimental en el que se analizaron tubos de silicona propios de la asistencia al paciente quirúrgico, en el período de septiembre a noviembre de 2015. Los tubos provenían del Centro de Material y Esterilización (CME) de un hospital general de gran tamaño de la región Centro-Oeste de Brasil. Los tubos fueron segmentados así: extremo 01, 02 y medio y nuevamente segmentados según intervalos de tiempo preestablecidos en cero, 12 y 24 horas. Los fragmentos se llenaron con agua estéril, fueron sellados y sometidos a cinco minutos de sonicación. El agua fue filtrada en Millipore 0,45 μm y las membranas incubadas a 35°C por 24 horas en agar nutriente. Las membranas fueron removidas y dispuestas en tubos de ensayo que contenían 1mL de solución salina, fueron agitados durante cinco minutos y sometidos a técnica de alza calibrada Resultados: Se observó un aumento de la carga microbiana en el orden de una magnitud en la escala logarítmica cada 12 horas (p <0,05), en las condiciones de limpieza y almacenamiento proporcionadas por la institución, en los grupos experimental y de control positivo. No hubo diferencia cuando se compararon el medio y los extremos de los tubos de silicona (p> 0,05) en los períodos cero, 12 y 24 horas. Conclusión: Dependiendo de la carga microbiana inicial, el aumento del orden de una magnitud puede resultar en el fracaso de la esterilización. Estos hallazgos ratifican la no permanencia de PPS en el área limpia mientras se aguarda el procesamiento.

Abstract Objective: To determine the microbial load of silicone tubes, immediately after cleaning, and at different storage intervals. Methods: Experimental study that analyzed silicone tubes from surgical patient care, conducted after approval by the Ethics Committee (protocol no. 1,277,077), from September to November of 2015, with tubes from the Central Processing Department (CPD) of a large general hospital in the West Central region of Brazil. The tubes were segmented (end 1 and 2, and the middle) and were then segmented again, according to established time intervals (zero, 12, and 24 hours). The fragments were filled with sterile water, sealed, and exposed to five minutes of sonication. The water was filtered via 0.45μm Millipore, and the membranes were incubated at 35°C for 24 hours, on nutrient agar. The membranes were removed and placed in test tubes containing 1mL of saline, which were mixed for five minutes, and subjected to a calibrated loop technique. Results: An increase in microbial load was identified, in the order of a logarithmic magnitude every 12 hours (p<0.05), in the cleaning and storage conditions provided by the institution, in the experimental and positive control groups, and no difference was identified when comparing the middle and ends of the silicone tubes (p> 0.05) at periods zero, 12, and 24 hours. Conclusion: Depending on the initial microbial load, an increase in the order of magnitude can result in sterilization failure, which corroborates the need to not maintain healthcare products in the storage place while awaiting processing.

Assessment of sodium fluoride 2% as a new method of disinfecting extracted human teeth / Avaliação de fluoreto de sódio 2% como um novo método de desinfecção dentes humanos extraídos

ABSTRACT Objective: Investigate the action of sodium fluoride 2% as a new method of disinfecting/sterilizing extracted human teeth, using E. faecalis. Methods: The survival rate of E. faecalis ATCC 29212 was assessed, in terms of absorbance from the culture media, using a spectrophotometer. The sterilization assessment was carried out in the following groups: Group I (GI) - control; GII - autoclave; GIII - sodium fluoride seven days; GIV - sodium fluoride 14 days. Results: When using the autoclave and sodium fluoride solution (2%), the quantity of bacteria reduced significantly when compared to the control group (p <0.001). Statistically significant differences were also found when the experimental groups were compared with each other (p < 0.001). Conclusion: The results of the present study suggest that sodium fluoride 2% solution can be considered a new disinfection method based on its capacity to reduce the load of E. faecalis.

RESUMO Objetivo: Investigar a ação do fluoreto de sódio à 2% como um novo método de desinfecção/esterilização de dentes humanos extraídos, usando E. faecalis. Métodos: A taxa de sobrevivência do E. faecalis ATCC 29212 foram avaliadas, em termos de absorbância a partir do meio de cultura, usando espectofotômetro. A avaliação de esterilização ocorreu de acordo com os seguintes grupos: Grupo I (GI) - controle; GII - autoclave; GIII - fluoreto de sódio 7 dias; GIV - fluoreto de sódio 14 dias. Resultados: Quando utilizado autoclave e solução de fluoreto de sódio (2%), a quantidade de bactérias foi reduzida significativamente quando comparado com o grupo de controle (p <0.001). Diferenças estatisticamente significantes também foram encontrados quando os grupos experimentais foram comparados uns com os outros (p < 0.001). Conclusão: Os resultados do presente estudo sugerem que a solução de fluoreto de sódio à 2% pode ser considerado como um novo método de desinfecção com base na sua capacidade para reduzir a carga de E. faecalis.

Effect of Passive Ultrasonic Irrigation on Enterococcus faecalis from Root Canals: An Ex Vivo Study

Endodontic irrigation aims to clean and disinfect the root canal system. Passive ultrasonic irrigation (PUI) is based on the use of an ultrasound-activated instrument into the root canal filled with irrigant. The aim of this study was to evaluate, ex vivo, the effectiveness of PUI in eliminating Enterococcus faecalis from root canals. Seventy-five extracted human single-root teeth were used. After root canal preparation, specimens were inoculated with E. faecalis and incubated at 37 °C for 21 days. Specimens were distributed into five groups (n=15), according to the irrigation method: PUI + saline solution (PUI/SS); PUI + 1% NaOCl (PUI/NaOCl); conventional needle irrigation (CNI) + saline solution (CNI/SS); CNI + 1% NaOCl (CNI/NaOCl); No irrigation (control). Microbiological samples were collected at three time points: initial (21 days after inoculation), post-irrigation (immediately after irrigation), and final (7 days after irrigation). Data were obtained in CFU mL^-1 and subjected to analysis by ANOVA and Tukey's tests at 5% significance level. The post-irrigation samples did not demonstrate statistical difference between PUI/SS and CNI/SS nor between PUI/NaOCl and CNI/NaOCl (p>0.05), but PUI/NaOCl and CNI/NaOCl had lower CFU mL^-1 number than the other groups (p>0.05). Statistically significant difference was observed between the initial and post-irrigation samples and between the post-irrigation and final samples (p<0.05) in all groups, except in the control. The final samples of all groups presented bacterial counts similar to the initial samples. PUI or CNI with 1% NaOCl contribute to disinfection, but are unable to eradicate E. faecalis from the root canal system.

A irrigação endodôntica visa à limpeza e desinfecção do sistema de canais radiculares. A irrigação ultrassônica passiva (IUP) baseia-se na utilização de um instrumento ultrassônico ativado no interior do canal radicular preenchido com a solução irrigadora. O objetivo deste estudo foi avaliar, ex vivo, a eficácia da IUP na eliminação de Enterococcus faecalis dos canais radiculares. Foram usados 75 dentes humanos unirradiculares extraídos. Após o preparo biomecânico dos canais radiculares, foram inoculados com E. faecalis e incubados a 37 °C por 21 dias. Os espécimes foram distribuídos em cinco grupos (n=15), de acordo com o método de irrigação: IUP + solução salina (IUP/SS); IUP + NaOCl a 1% (IUP/NaOCl); irrigação manual convencional (IMC) + solução salina (IMC/sol); IMC + NaOCl a 1% (IMC/NaOCl); Sem irrigação (controle). Foram realizadas três coletas microbiológicas: inicial (21 dias após a inoculação), pós-irrigação (imediatamente após a irrigação), e final (7 dias após a irrigação). Os dados foram obtidos em UFC mL^-1 e submetidos aos testes de ANOVA e Tukey. A coleta pós-irrigação não demonstrou diferença estatisticamente significante entre IUP/SS e IMC/SS nem entre IUP/NaOCl e IMC/NaOCl (p>0,05), mas IUP/NaOCl e IMC/NaOCl apresentaram menor número de UFC mL^-1 comparado aos outros grupos (p>0,05). Diferença estatisticamente significante foi observada entre as coletas iniciais e pós-irrigação e entre a pós-irrigação e a coleta final (p<0,05) em todos os grupos, exceto no controle. Na coleta final, todos os grupos apresentaram contagem bacteriana similar à coleta inicial. IUP ou IMC com NaOCl a 1% contribuem para a desinfecção, mas não eliminam E. faecalis do sistema de canais radiculares.

Antimicrobial activity of complete denture cleanser solutions based on sodium hypochlorite and Ricinus communis: a randomized clinical study

ABSTRACT To preserve oral health and to maintain the prosthetic devices, it is important not only to improve the properties of commonly known hygiene products, but also to investigate new materials with antimicrobial action. Objectives This study evaluated the antimicrobial activity of sodium hypochlorite (0.25% and 0.50%) and 10% Ricinus communis’ solutions against specific microorganisms. Material and Methods Sixty four maxillary complete denture wearers were instructed to brush their dentures three times a day and to soak them (20 min/day) in the solutions: SH1: 0.25% sodium hypochlorite; SH2: 0.5% sodium hypochlorite; RC: 10% R. communis oil; and C: 0.85% saline (control). The solutions were used for 7 days in a randomized sequence. Following each period of use, there was a 1-week washout period. Antimicrobial activity was determined by Colony Forming Units (CFU) counts of Streptococcus mutans, Candida spp., and gram-negative microorganisms. For collecting biofilm, the internal surface of maxillary dentures was brushed with saline solution, and biofilm suspension obtained. After dilutions (100 - 10-3), aliquots were seeded in Mitis salivarius, CHROMagar Candida®, and MacConkey agar for detecting S. mutans, Candida spp., or gram-negative microorganisms, respectively. After incubation, colonies were counted, and CFU/mL values were calculated. Then, transformation - log10 (CFU+1) - data were analyzed using the Friedman test (α=0.05). Results showed significant differences between the solutions (p<0.001). Results All three solutions showed antimicrobial activity against S. mutans. Against Candida spp., RC and SH1 solutions showed similar effect while SH2 showed superior activity. SH1 and SH2 solutions showed antimicrobial action against gram-negative microorganisms. The Candida species most frequently isolated was C. albicans, followed by C. tropicalis and C. glabrata. Conclusions The 0.5% sodium hypochlorite solution was the most effective and might be used to control denture biofilm. C. albicans was the most frequently isolated Candida sp.

In Vitro Antimicrobial Activity of an Experimental Dentifrice Based on Ricinus Communis

This study evaluated the antimicrobial activity of a Ricinus communis-based experimental dentifrice for denture hygiene against the following standard strains: Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Candida albicans and Candida glabrata. The minimum inhibitory concentration (MIC) assay was performed with R. communis in pure oil at 2.5%. Only E. coli was not inhibited by R. communis, but the MIC (0.0781%) was effective against the other microorganisms. From these results it was determined the R. communis concentrations for experimental dentifrices, 1, 2, 5 and 10%, which were evaluated by the test-well diffusion in agar. The commercial dentifrices Colgate, Trihydral and Corega Brite were tested for comparative purposes. The diameter of the zones of bacterial growth inhibition produced around the wells was measured (in mm) with a rule under reflected light. Data were analyzed statistically by analysis of variance and Tukey's post-hoc test (α=0.05). Neither the commercial nor the experimental dentifrices were effective against E. coli. The experimental dentifrices containing R. communis at 2, 5 and 10% presented action against S. mutans, S. aureaus and E. faecallis. The experimental dentifrices showed no antimicrobial activity against Candida spp. and E. coli in any of the tested concentrations. Trihydral was the most effective. Comparing the experimental dentifrices, the product with 10% R. communis produced the largest zones of bacterial growth inhibition and had similar antimicrobial activity to the commercial dentifrices, except against S. aureus.

Este estudo avaliou a atividade antimicrobiana de um dentifrício experimental a base de Ricinus communis para higiene de prótese contra as seguintes cepas padrão: Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Candida albicans e Candida glabrata. O ensaio de concentração inibitória mínima foi realizado com R. communis em óleo puro a 2,5 % . Apenas a E. coli não foi inibida por R. communis, no entanto, a concentração mínima (0,0781%) foi eficaz contra os outros microrganismos. A partir destes resultados foram determinadas as concentrações dos dentifrícios experimentais: 1, 2, 5 e 10 %, as quais foram avaliadas pelo teste de difusão em Agar. Os dentifrícios comerciais Colgate, Trihydral e Corega Brite foram testados para fins comparativos. O diâmetro dos halos de inibição do crescimento bacteriano, em torno dos poços, foi medido (em mm) com uma régua sob uma luz refletida. Os dados foram analisados estatisticamente por meio de análise de variância e teste post-hoc de Tukey (α=0,05). Nem os dentifrícios comerciais nem os experimentais foram eficazes contra E. coli. Os dentifrícios experimentais contendo R. communis a 2 , 5 e 10 % apresentaram ação contra S. mutans, S. aureaus e E. faecallis. Os dentifrícios experimentais não mostraram atividade antimicrobiana contra Candida spp e E. coli em nenhuma das concentrações testadas . O Trihydral foi o mais eficaz. Comparando os dentifrícios experimentais, o produto com 10% de R. communis produziu os maiores halos de inibição do crescimento microbiano e apresentou atividade antimicrobiana.

Development of a novel resin with antimicrobial properties for dental application

The adhesion of biofilm on dental prostheses is a prerequisite for the occurrence of oral diseases. Objective: To assess the antimicrobial activity and the mechanical properties of an acrylic resin embedded with nanostructured silver vanadate (β-AgVO3). Material and Methods: The minimum inhibitory concentration (MIC) of β-AgVO3 was studied in relation to the species Staphylococcus aureus ATCC 25923, Streptococcus mutans ATCC 25175, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231. The halo zone of inhibition method was performed in triplicate to determine the inhibitory effect of the modified self-curing acrylic resin Dencor Lay - Clássico®. The surface hardness and compressive strength were examined. The specimens were prepared according to the percentage of β-AgVO3 (0%-control, 0.5%, 1%, 2.5%, 5%, and 10%), with a sample size of 9x2 mm for surface hardness and antimicrobial activity tests, and 8x4 mm for the compression test. The values of the microbiologic analysis were compared and evaluated using the Kruskal-Wallis test (α=0.05); the mechanical analysis used the Shapiro-Wilk's tests, Levene's test, ANOVA (one-way), and Tukey's test (α=0.05). Results: The addition of 10% β-AgVO3 promoted antimicrobial activity against all strains. The antimicrobial effect was observed at a minimum concentration of 1% for P. aeruginosa, 2.5% for S. aureus, 5% for C. albicans, and 10% for S. mutans. Surface hardness and compressive strength increased significantly with the addition of 0.5% β-AgVO3 (p<0.05). Higher rates of the nanomaterial did not alter the mechanical properties of the resin in comparison with the control group (p>0.05). Conclusions: The incorporation of β-AgVO3 has the potential to promote antimicrobial activity in the acrylic resin. At reduced rates, it improves the mechanical properties, and, at higher rates, it does not promote changes in the control. .

Microbiological Evaluation of Different Irrigation Protocols on Root Canal Disinfection in Teeth with Apical Periodontitis: An In Vivo Study

The present in vivo study was designed to evaluate the efficacy of apical negative pressure irrigation (ANP), passive ultrasonic irrigation (PUI) and positive pressure irrigation (PP) in the reduction of intracanal bacteria of dogs' teeth with pulp necrosis and apical periodontitis. Eighty root canals were randomly distributed into 3 experimental and 2 control groups according to the irrigation delivery system: group ANP (n=20), group PUI (n=20), group PP (n=20), group PC (positive control – sterile saline irrigation; n=10) and group NC (negative control - vital pulps not subjected to bacterial inoculation; n=10). The first sample (S1) was collected at baseline, and the second sample (S2) was collected after the disinfection protocols. All samples were seeded in culture media for anaerobic bacteria. CFU counts were analyzed statistically by the Kruskal-Wallis, Dwass-Steel-Critchlow-Fligner post-hoc and Chi-square followed by Tukey like multiple comparisons for proportions (α=0.05). All experimental groups were effective in reducing Gram-positive bacteria compared with PC (p<0.05). Regarding the reduction of Gram-negative bacteria, group ANP was significantly better than PP (p<0.05). No statistically significant difference could be found between PP and PUI (p>0.05). In dog's teeth with apical periodontitis, the use of ANP and PUI can be considered promising disinfection protocols as both delivery systems promoted a significant bacterial reduction.

O presente estudo foi conduzido para avaliar a eficácia da irrigação por pressão apical negativa (ANP), irrigação ultrassônica passiva (PUI) e irrigação por pressão positiva (PP) na redução do número de bactérias presentes nos canais radiculares de dentes de cães com necrose pulpar e lesão periapical. Um total de 80 canais radiculares foram aleatoriamente distribuídos em 3 grupos experimentais e 2 grupos controles, de acordo com o sistema de irrigação empregado: grupo ANP (n=20), grupo PUI (n=20), grupo PP (n=20), grupo PC (controle positivo – irrigação com solução salina; n=10) e grupo NC (controle negativo – tecido pulpar com vitalidade, não submetido à contaminação bacteriana; n=10). A primeira amostra (S1) foi coletada no início do estudo, e a segunda amostra (S2) foi coletada após a utilização dos protocolos de irrigação. Todas as amostras foram semeadas em meio de cultura para micro-organismos anaeróbios. As contagens de unidades formadoras de colônia (cfu) foram analisadas estatisticamente por meio dos testes de Kruskal-Wallis, pós-teste de Dwass-Steel-Critchlow-Fligner e teste do qui-quadrado seguido do teste Tukey like para comparações múltiplas (α=0,05). Todos os grupos experimentais foram efetivos na redução de micro-organismos Gram-positivos, comparados ao grupo PC (p<0,05). Com relação à redução de microorganismos Gram-negativos, o grupo ANP foi significantemente melhor que o PP (p<0,05). Não foi possível observar diferença estatisticamente significante entre os grupos PP e PUI (p>0,05). Conclui-se que, em dentes de cães com periodontite apical, os sistemas de irrigação ANP e PUI podem ser considerados métodos promissores, uma vez que ambos os protocolos promoveram uma redução bacteriana significante.

Evaluation of pH, calcium ion release and antimicrobial activity of a new calcium aluminate cement

This study evaluated the pH, calcium ion release and antimicrobial activity of EndoBinder (EB), containing different radiopacifiers: bismuth oxide (Bi2O3), zinc oxide (ZnO) or zirconium oxide (ZrO2), in comparison to MTA. For pH and calcium ion release tests, 5 specimens per group (n = 5) were immersed into 10 mL of distilled and deionized water at 37°C. After 2, 4, 12, 24, 48 h; 7, 14 and 28 days, the pH was measured and calcium ion release quantified in an atomic absorption spectrophotometer. For antimicrobial activity, the cements were tested against S. aureus, E. coli, E. faecalis and C. albicans, in triplicate. MTA presented higher values for pH and calcium ion release than the other groups, however, with no statistically significant difference after 28 days (p > 0.05); and the largest inhibition halos for all strains, with no significant difference (E. coli and E. faecalis) for pure EB and EB + Bi2O3 (p > 0.05). EB presented similar performance to that of MTA as regards pH and calcium ion release; however, when ZnO and ZrO2 were used, EB did not present antimicrobial activity against some strains.

Complete denture biofilm after brushing with specific denture paste, neutral soap and artificial saliva

This study compared the levels of biofilm in maxillary and mandibular complete dentures and evaluated the number of colony-forming units (cfu) of yeasts, after using auxiliary brushing agents and artificial saliva. Twenty-three denture wearers with hyposalivation and xerostomia were instructed to brush the dentures 3 times a day during 3 weeks with the following products: Corega Brite denture dentifrice, neutral liquid soap, Corega Brite combined with Oral Balance (artificial saliva) or tap water. For biofilm quantification, the internal surfaces of the dentures were disclosed, photographed and measured using a software. For microbiological analysis, the biofilm was scrapped off, and the harvested material was diluted, sown in CHROMagar™ Candida and incubated at 37°C for 48 h. Data were analyzed statistically by two-way ANOVA and Tukey's test (α=0.05). Mandibular dentures presented a mean biofilm percentage (µ=26.90 ± 21.10) significantly greater than the maxillary ones (µ=18.0 ± 15.0) (p<0.05). Brushing using Corega Brite combined with Oral Balance (µ=15.87 ± 18.47) was more effective (p<0.05) than using the denture dentifrice (µ=19.47 ± 17.24), neutral soap (µ=23.90 ± 18.63) or tap water (control; µ=32.50 ± 20.68). For the microbiological analysis, the chi-square test did not indicate significant difference between the hygiene products for either type of denture. The more frequently isolated species of yeasts were C. albicans, C. tropicalis and C. glabrata. In conclusion, mandibular dentures had more biofilm formation than maxillary ones. Denture brushing with Corega Brite dentifrice combined with the use of Oral Balance was the most effective method for reduction of biofilm levels, but the use of products did not show difference in yeast cfu counts.

Este estudo comparou os níveis de biofilme em próteses totais maxilares e mandibulares, e analisou o número de unidades formadoras de colônias de leveduras, após o uso de agentes auxiliares da escovação e saliva artificial. Vinte e três usuários de próteses totais com hipossalivação e xerostomia foram orientados a escovar as dentaduras 3 vezes ao dia durante 3 semanas com os seguintes produtos: Corega Brite (dentifrício para prótese), sabonete líquido neutro, Corega Brite associado com o uso do Oral Balance (saliva artificial) ou água de torneira. Para a quantificação do biofilme, as superfícies internas das próteses totais foram evidenciadas, fotografadas e o biofilme quantificado com o auxílio de um software. Para a análise microbiológica, o biofilme foi removido por escovação, coletado, diluído, semeado em meio seletivo CHROMagar™ Candida e incubado a 37°C por 48 h. A análise de variância para dois fatores (p<0,05%) mostrou que as próteses mandibulares apresentaram uma média de porcentagem de biofilme (µ=26,90±21,10) maior que as maxilares (µ=18±15). O teste complementar de Tukey (0,46; p<5%) mostrou que a escovação com Corega Brite e Oral Balance (µ=15,87 ± 18,47) foi mais efetiva que o dentifrício (µ=19,47 ± 17,24), sabonete neutro (µ=23,90 ± 18,63), ou água de torneira (controle; µ=32,50 ± 20,68). Em relação á análise microbiológica, o teste de Qui-Quadrado não indicou diferença entre os produtos de higiene, para ambas as próteses. As espécies de leveduras mais comumente isoladas foram C. albicans, C. tropicalis e C. glabrata. Em conclusão, as próteses mandibulares apresentaram mais biofilme do que as maxilares. Além disso, a escovação das próteses com o Corega Brite associado ao uso do Oralbalance foi o método mais efetivo na redução dos níveis de biofilme, entretanto o uso dos produtos não demonstrou diferença no número de ufc de leveduras.