RESUMEN
AIM: The objective of the present study was to determine if blood plasma proteins could change the proteome of the acquired denture pellicle by label-free quantitative proteomics. As pellicle proteome modulates the interaction between substrates and Candida cells, we investigated its effect on the surface free energy (SFE) of the coated resin and on Candida albicans phospholipase and aspartyl proteinase activities. METHODS: Poly(methylmethacrylate) discs were exposed to saliva (control) or saliva enriched with blood plasma (experimental group). The pellicle proteome was analyzed by mass spectrometry coupled with liquid chromatography. SFE was determined by acid-base technique. After biofilm formation, phospholipase and proteinase activities were determined accordingly to classic plate methods. Data were analyzed by two-way anova and Tukey test (P < 0.05). RESULTS: α-Amylase, cystatins, mucins, and host-immune system proteins were the main proteins identified in the control group. Fibrinogen and albumin were observed only in the experimental group. Coated discs of the experimental group presented an increased SFE (P < 0.05). For both enzymes tested, the experimental group showed higher proteolytic activity (P < 0.001). CONCLUSION: Blood plasma changes the proteome of the acquired denture pellicle, increasing surface free energy and the activity of Candida albicans phospholipase and aspartyl proteinase.
Asunto(s)
Proteasas de Ácido Aspártico/análisis , Proteínas Sanguíneas/fisiología , Candida albicans/enzimología , Película Dental/fisiología , Bases para Dentadura , Fosfolipasas/análisis , Polimetil Metacrilato/química , Adulto , Biopelículas , Proteínas Sanguíneas/análisis , Cromatografía Liquida/métodos , Cistatinas/análisis , Película Dental/química , Femenino , Fibrinógeno/análisis , Humanos , Inmunoproteínas/análisis , Técnicas In Vitro , Masculino , Mucinas/análisis , Proteoma/metabolismo , Distribución Aleatoria , Albúmina Sérica/análisis , Tensión Superficial , Espectrometría de Masas en Tándem/métodos , alfa-Amilasas/análisisRESUMEN
BACKGROUND: It is well known that the use of denture cleansers can reduce Candida albicans biofilm accumulation; however, the efficacy of citric acid denture cleansers is uncertain. In addition, the long-term efficacy of this denture cleanser is not well established, and their effect on residual biofilms is unknown. This in vitro study evaluated the efficacy of citric acid denture cleanser treatment on C. albicans biofilm recolonization on poly(methyl methacrylate) (PMMA) surface. METHODS: C. albicans biofilms were developed for 72 h on PMMA resin specimens (n = 168), which were randomly assigned to 1 of 3 cleansing treatments (CTs) overnight (8 h). CTs included purified water as a control (CTC) and two experimental groups that used either a 1:5 dilution of citric acid denture cleanser (CT5) or a 1:8 dilution of citric acid denture cleanser (CT8). Residual biofilms adhering to the specimens were collected and quantified at two time points: immediately after CTs (ICT) and after cleaning and residual biofilm recolonization (RT). Residual biofilms were analyzed by quantifying the viable cells (CFU/mL), and biofilm architecture was evaluated by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Denture cleanser treatments and evaluation periods were considered study factors. Data were analyzed using two-way ANOVA and Tukey's Honestly Significant Difference (HSD) test (α = 0.05). RESULTS: Immediately after treatments, citric acid denture cleansing solutions (CT5 and CT8) reduced the number of viable cells as compared with the control (p < 0.01). However, after 48 h, both CT groups (CT5 and CT8) showed biofilm recolonization (p < 0.01). Residual biofilm recolonization was also detected by CLSM and SEM analysis, which revealed a higher biomass and average biofilm thickness for the CT8 group (p < 0.01). CONCLUSION: Citric acid denture cleansers can reduce C. albicans biofilm accumulation and cell viability. However, this CT did not prevent biofilm recolonization.
Asunto(s)
Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Ácido Cítrico/farmacología , Materiales Dentales/química , Limpiadores de Dentadura/farmacología , Polimetil Metacrilato/química , Biopelículas/crecimiento & desarrollo , Biomasa , Candida albicans/crecimiento & desarrollo , Recuento de Colonia Microbiana , Película Dental/fisiología , Humanos , Técnicas In Vitro , Ensayo de Materiales , Viabilidad Microbiana , Microscopía Confocal , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Factores de Tiempo , Agua/químicaRESUMEN
OBJECTIVE: In studies on Candida albicans adhesion to surfaces, diverse protocols have been used for collection and preparation of saliva samples. Thus, this study investigated whether variations in the centrifugation parameters and number of donors of saliva would influence the adhesion of C. albicans to a denture base resin. METHODS: Resin acrylic samples (n = 72) were made and then divided into four groups: (a) control - specimens were left without preconditioning in saliva; (b) three experimental groups, in which the specimens were preconditioned with saliva collected from 15 volunteers and centrifuged at 12 000 g for 5 min (G1 ); from 15 volunteers and centrifuged at 18 000 g for 30 min (G2 ); and from one volunteer and centrifuged at 12 000 g for 5 min (G3 ). Candida adhesion was evaluated by both the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide (XTT) reduction method and crystal violet staining. Data were analyzed by one-way analyses of variance (P = 0.05). RESULTS: For XTT reduction assay, groups G2 , G3 , and control were not significantly different, whereas group G1 showed significantly higher absorbance value than control. For crystal violet staining there were no significant differences among all groups. CONCLUSION: Variations in the centrifugation parameters and number of donors of saliva may influence C. albicans adhesion to denture base resins.
Asunto(s)
Resinas Acrílicas/química , Candida albicans/fisiología , Materiales Dentales/química , Bases para Dentadura/microbiología , Saliva/fisiología , Adhesividad , Recuento de Colonia Microbiana , Colorantes , Película Dental/fisiología , Violeta de Genciana , Humanos , Indicadores y Reactivos , Manejo de Especímenes/métodos , Sales de Tetrazolio , Factores de TiempoRESUMEN
Although some studies suggest an anticaries effect of fluoridated bovine milk (F-milk) on enamel, evidence is still considered weak. Even more uncertain, the effect of F-milk on root caries remains largely unknown. This study evaluated the effect of F-milk on enamel and on root dentin demineralization using a validated Streptococcus mutans biofilm model, simulating a high cariogenic challenge. S. mutans (UA159) biofilms were formed on bovine enamel and root dentin saliva-coated slabs after measuring initial surface microhardness (SH). Biofilms were exposed to 10% sucrose 8×/day and treated 2×/day with either: (1) 0.9% NaCl (negative control), (2) bovine milk, (3) F-milk (5.0 ppm F as NaF) or (4) NaF 0.05% (anticaries-positive control). Medium pH was monitored twice/day, as a biofilm acidogenicity indicator. After 5 days for enamel and 4 days for dentin, biofilms were recovered to analyze: biomass, soluble proteins, viable microorganisms, and extra- and intracellular polysaccharides. Enamel and dentin demineralization were estimated by percentage of SH loss. Results were compared by ANOVA and Tukey's test. Neither acidogenicity nor biofilm composition differed among treatment groups in biofilms formed on enamel or dentin (p > 0.05). F-milk, however, significantly reduced enamel and dentin demineralization when compared with the negative control (p < 0.05). Also, F-milk was as efficient as 0.05% NaF to reduce enamel (p > 0.05), but not dentin demineralization (p < 0.05). These findings suggest that milk containing 5.0 ppm of fluoride is effective to control enamel caries and that it may be effective on root dentin caries prevention.
Asunto(s)
Biopelículas , Cariostáticos/administración & dosificación , Esmalte Dental/efectos de los fármacos , Dentina/efectos de los fármacos , Fluoruros/administración & dosificación , Leche , Streptococcus mutans/fisiología , Desmineralización Dental/prevención & control , Raíz del Diente/efectos de los fármacos , Animales , Proteínas Bacterianas/análisis , Biomasa , Cariogénicos/farmacología , Bovinos , Caries Dental/microbiología , Película Dental/fisiología , Dureza , Humanos , Concentración de Iones de Hidrógeno , Viabilidad Microbiana , Polisacáridos Bacterianos/química , Saliva/fisiología , Fluoruro de Sodio/administración & dosificación , Streptococcus mutans/efectos de los fármacos , Sacarosa/farmacología , Factores de Tiempo , Desmineralización Dental/microbiologíaRESUMEN
UNLABELLED: The adhesion of Candida albicans to surfaces is the prerequisite for occurrence of denture stomatitis. OBJECTIVE: Hence, this study investigated if surface modifications with plasma treatments could reduce the adherence of C. albicans to a denture base resin. METHODS: Specimens (n=180) with roughened and smooth surfaces were made and divided into five groups: control-specimens were left untreated; experimental groups-specimens were submitted to plasma treatments to obtain surfaces with different hydrophobicity (Ar/50W; ArO2/70W; AAt/130W) or incorporation of fluorine (Ar/SF(6)70W). Contact angle measurements were performed immediately after the treatments and after immersion in water for 48h. For each group, half of the specimens were incubated with saliva prior to the adhesion assay. The number of adherent yeasts was evaluated by XTT reduction method. RESULTS: For the experimental groups, there was significant change in the mean contact angle after 48h of immersion in water. Groups ArO2/70W and ArSF6/70W showed significantly lower absorbance readings than the other groups, regardless the presence or absence of saliva and surface roughness. CONCLUSIONS: Results demonstrated that ArO2/70W and ArSF6/70W plasma treatments showed promising potential for reducing the adherence of C. albicans to denture base resins.
Asunto(s)
Candida albicans/fisiología , Adhesión Celular/efectos de los fármacos , Bases para Dentadura , Gases em Plasma/farmacología , Resinas Acrílicas , Adulto , Argón , Recuento de Colonia Microbiana , Colorantes , Película Dental/fisiología , Humanos , Propiedades de Superficie , Sales de Tetrazolio , HumectabilidadRESUMEN
AIM: The role of saliva on Candida adhesion to biomaterials has not been clearly defined. The present study investigates whether different periods of preconditioning with saliva would influence the adhesion of Candida albicans to a denture base resin. METHODS: Ninety samples of acrylic resin with smooth surfaces were made and then divided into five groups: one control without saliva, and four experimental groups conditioned in saliva for periods of 30 min, 1, 3, or 12 h. Candida adhesion was evaluated by crystal violet staining and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-([phenylamino] carbonyl)-2H-tetrazolium-hydroxide assay. RESULTS: The one-way analysis of variance revealed that there were no significant differences among the mean number of adherent cells or among the mean absorbance for all groups. No significant correlation was found between the two methods used for assessing Candida albicans adhesion. CONCLUSION: The different periods of preconditioning with saliva had no significant influence on the adhesion of Candida albicans to the denture base acrylic resin.
Asunto(s)
Resinas Acrílicas/química , Candida albicans/fisiología , Materiales Dentales/química , Película Dental/fisiología , Bases para Dentadura/microbiología , Saliva/fisiología , Adhesividad , Adulto , Recuento de Colonia Microbiana , Colorantes , Violeta de Genciana , Humanos , Indicadores y Reactivos , Fenómenos Microbiológicos , Propiedades de Superficie , Sales de Tetrazolio , Factores de TiempoRESUMEN
This paper discusses the role of dental biofilm and adjunctive therapies in the management of dental caries. Dental biofilm is a site of bacterial proliferation and growth, in addition to being a location of acid production. It also serves as a reservoir for calcium exchange between the tooth and saliva. The salivary pellicle, a protein-rich biofilm layer, regulates the reaction between tooth surface, saliva and erosive acids. The protective effects of this pellicle on enamel are well established. However, understanding the effects of the pellicle/biofilm interaction in protecting dentin from erosive conditions requires further research. Saliva interacts with the biofilm, and is important in reducing the cariogenic effects of dental plaque as acidogenic bacteria consume fermentable carbohydrates producing acids that may result in tooth demineralization. Adequate supplies of healthy saliva can provide ingredients for successful remineralization. Strategies for managing the cariogenic biofilm are discussed with emphasis on the effectiveness of over-the-counter (OTC) products. However, since many toothpaste components have been altered recently, new clinical trials may be required for true validation of product effectiveness. A new generation of calcium-based remineralizing technologies may offer the ability to reverse the effects of demineralization. Nevertheless, remineralization is a microscopic subsurface phenomenon, and it will not macroscopically replace tooth structure lost in a cavitated lesion. Optimal management of cavitations requires early detection. This, coupled with advances in adhesive restorative materials and microsurgical technique, will allow the tooth to be restored with minimal destruction to nearby healthy tissue.
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Biopelículas , Caries Dental/prevención & control , Película Dental/fisiología , Placa Dental/prevención & control , Saliva/fisiología , Animales , Antiinfecciosos/uso terapéutico , Biopelículas/crecimiento & desarrollo , Calcio/química , Caries Dental/microbiología , Placa Dental/microbiología , Humanos , Fosfatos/química , Saliva/química , Saliva/microbiología , Diente/química , Diente/microbiología , Remineralización DentalRESUMEN
OBJECTIVE: This in situ/ex vivo study assessed the erosive potential of a light cola drink when compared to a regular one. METHODS: During 2 experimental 14-days crossover phases, eight volunteers wore palatal devices with 2 human enamel blocks. The groups under study were: group light, erosive challenge with light cola drink and group regular, erosive challenge with regular cola drink. During 14 days, erosive challenges were performed extraorally 3X/day. In each challenge, the device was immersed in 150ml of light cola (group light) or regular cola (group regular) for 5min. Erosion was analysed by surface profilometry (microm) and surface microhardness change (%SMH). The data were statistically analyzed using paired t test (p<0.05). RESULTS: Group light (0.6+/-0.2microm) showed significantly lesser wear than group regular (3.1+/-1.0microm). There was no significant difference between the groups for the %SMH (group light -63.9+/-13.9 and group regular -78.5+/-12.7). CONCLUSIONS: The data suggest that the light cola drink is less erosive than the regular one.
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Bebidas Gaseosas/efectos adversos , Erosión de los Dientes/etiología , Adulto , Calcio/análisis , Bebidas Gaseosas/análisis , Bebidas Gaseosas/clasificación , Estudios Cruzados , Esmalte Dental/patología , Película Dental/fisiología , Fluoruros/análisis , Dureza , Humanos , Concentración de Iones de Hidrógeno , Fósforo/análisis , Adulto JovenRESUMEN
This paper discusses the role of dental biofilm and adjunctive therapies in the management of dental caries. Dental biofilm is a site of bacterial proliferation and growth, in addition to being a location of acid production. It also serves as a reservoir for calcium exchange between the tooth and saliva. The salivary pellicle, a protein-rich biofilm layer, regulates the reaction between tooth surface, saliva and erosive acids. The protective effects of this pellicle on enamel are well established. However, understanding the effects of the pellicle/biofilm interaction in protecting dentin from erosive conditions requires further research. Saliva interacts with the biofilm, and is important in reducing the cariogenic effects of dental plaque as acidogenic bacteria consume fermentable carbohydrates producing acids that may result in tooth demineralization. Adequate supplies of healthy saliva can provide ingredients for successful remineralization. Strategies for managing the cariogenic biofilm are discussed with emphasis on the effectiveness of over-the-counter (OTC) products. However, since many toothpaste components have been altered recently, new clinical trials may be required for true validation of product effectiveness. A new generation of calcium-based remineralizing technologies may offer the ability to reverse the effects of demineralization. Nevertheless, remineralization is a microscopic subsurface phenomenon, and it will not macroscopically replace tooth structure lost in a cavitated lesion. Optimal management of cavitations requires early detection. This, coupled with advances in adhesive restorative materials and microsurgical technique, will allow the tooth to be restored with minimal destruction to nearby healthy tissue.
Asunto(s)
Animales , Humanos , Biopelículas , Caries Dental/prevención & control , Película Dental/fisiología , Placa Dental/prevención & control , Saliva/fisiología , Antiinfecciosos/uso terapéutico , Biopelículas/crecimiento & desarrollo , Calcio/química , Caries Dental/microbiología , Placa Dental/microbiología , Fosfatos/química , Saliva/química , Saliva/microbiología , Remineralización Dental , Diente/química , Diente/microbiologíaRESUMEN
In the present study, we evaluated the ability of lectin from Talisia esculenta (TEL) and a protein from Labramia bojeri seeds (Labramin) to inhibit adherence of microorganisms and exert antimicrobial effects. The minimum inhibitory and bactericidal concentrations of these proteins were determined using 5 species of bacteria: Streptococcus mutans UA159, Streptococcus sobrinus 6715, Streptococcus sanguinis ATCC10556, Streptococcus mitis ATCC903 and Streptococcus oralis PB182. In addition, an adherence assay was performed using these 5 bacterial species and sterile polystyrene microtiter plates coated with human saliva. Filtered protein solutions (6.25 to 100 mug/ml) were added to saliva-coated plates, and the plates were then incubated for 1 h at 37 degrees C. After incubation, the plates were washed, and a bacterial suspension (10(6 )CFU/ml) was then transferred to each plate, followed by incubation at 37 degrees C for 1 h (10% CO(2)). Adherence of bacteria to the acquired pellicle was visualized by staining with crystal violet, and absorbance was measured using a plate reader at 575 nm. Neither Labramin nor TEL, at any of the concentrations used, inhibited growth of any of the microorganisms. However, Labramin inhibited adherence of S. mutans and S. sobrinus. The present results indicate that Labramin is potentially useful as a biofilm-inhibiting drug.
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Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Película Dental/fisiología , Lectinas de Plantas/farmacología , Streptococcus/fisiología , Recuento de Colonia Microbiana , Humanos , Pruebas de Sensibilidad Microbiana , Streptococcus/efectos de los fármacosRESUMEN
The acquired dental pellicle helps prevent erosion, but the protection level is unknown. This in situ study tested whether a two-hour pellicle protects against different erosive challenges by orange juice. Subjects wore palatal appliances loaded with either enamel or dentin specimens. Pellicle was allowed to form, or not (control), on the surfaces of the specimens intra-orally for 2 hrs before the erosive challenges of 0 (control), 10, 20, and 30 minutes' duration. Specimens were randomly removed from the appliances after each challenge. Percentage of surface microhardness change (%SMC) was determined for the enamel specimens, and that of mineral loss and lesion depth for the dentin specimens. Enamel specimens with the pellicle showed a significantly lower %SMC, only after the 10-minute challenge. No protection was found for dentin. It was concluded that the acquired pellicle reduced dental erosion, but that this effect was limited to the less severe erosive challenge on enamel surfaces.