Antibiofilm activity of irrigating solutions associated with cetrimide. Confocal laser scanning microscopy

AimTo evaluate the antibiofilm activity of sodium hypochlorite (NaOCl) and chlorhexidine (CHX) solutions associated with cetrimide (CTR), and QMiX using confocal laser scanning microscopy.MethodologyEnterococcus faecalis (ATCC- 29212) biofilms were induced on bovine dentine blocks for 14days. The dentine blocks containing biofilm were immersed for 1min in the following solutions: 2.5% NaOCl; 2.5% NaOCl+0.2% CTR; 2% CHX; 2% CHX+0.2% CTR; 0.2% CTR; QMiX. After contact with the solutions, the dentine blocks were stained with Live/Dead((R)) BacLight for analysis of the remaining biofilm using confocal laser scanning microscope. Images were evaluated using the BioImage_L software to determine the total biovolume (m(3)), the green biovolume (live cells) (m(3)) and the percentage of substrate coverage (%). The data were subjected to nonparametric statistical test using Kruskal-Wallis and Dunn's tests at 5% significance level.ResultsAfter exposure to irrigants, the total biovolume observed for CHX, CHX+CTR, CTR, QMiX was similar to distilled water (P>0.05). NaOCl and NaOCl+CTR had the lowest total and green biovolume. The CTR and QMiX had intermediate green biovolume, with greater antibacterial activity than CHX and CHX+CTR (P<0.05). The NaOCl and NaOCl+CTR solutions were associated with microorganism removal and substrate cleaning ability.ConclusionsNaOCl and NaOCl+CTR solutions were effective on microorganism viability and were able to eliminate biofilm. The addition of cetrimide did not influence antibacterial activity.

Water activity of aqueous solutions of ethylene oxide-propylene oxide block copolymers and maltodextrins

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A Family of Stationary Solutions to the Euler Equations and Generalized Solutions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effectiveness of several solutions to prevent the formation of precipitate due to the interaction between sodium hypochlorite and chlorhexidine and its effect on bond strength of an epoxy-based sealer

To evaluate the effectiveness of isopropyl alcohol, saline or distilled water to prevent the precipitate formed between sodium hypochlorite (NaOCl) and chlorhexidine (CHX) and its effect on the bond strength of an epoxy-based sealer in radicular dentine. Methodology The root canals of 50 extracted human canines (n = 10) were instrumented. In G1, root canals were irrigated with 17% EDTA and 2.5% NaOCl; G2, as G1, except that 2% CHX was used as the final irrigant. In the other groups, intermediate flushes with isopropyl alcohol (G3), saline (G4) or distilled water (G5) were used between NaOCl and CHX. The specimens were submitted to SEM analysis to evaluate the presence of debris and smear layer, in the apical and cervical segments. In sequence, fifty extracted human canines were distributed into five groups (n = 10), similar to the SEM study. After root filling, the roots were sectioned transversally to obtain dentine slices, in the cervical, middle and apical thirds. The root filling was submitted to a push-out bond strength test using an electromechanical testing machine. Statistical analysis was performed using Kruskal–Wallis and Dunn's tests (α = 5%). Results All groups had similar amounts of residue precipitated on the canal walls (P > 0.05). The push-out bond strength values were similar for all groups, independently of the root third evaluated (P > 0.05). Conclusions Isopropyl alcohol, saline and distilled water failed to prevent the precipitation of residues on canal walls following the use of NaOCl and CHX. The residues did not interfere with the push-out bond strength of the root filling.

Effect of protective solutions and hydroxyethyl starch in the attenuation of the injuries of ischemia and reperfusion of splanchnic organs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of different solutions on color stability of acrylic resin-based dentures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anticariogenic potencial of acidulate solutions with low fluoride concentration

Objetives: The aim of this study was to verify the anticariogenic effect of acidulate solutions with low NaF concentration, using pH-cycling model and bovine enamel. Material and Methods: Enamel blocks were submitted to the surface microhardness (SMH) test and randomly divided in 12 experimental and one placebo groups. The blocks were submitted to pH cycling for 7 days, with daily applications once/day of 0.05% NaF and 0.1% NaF and twice/day of 0.02% NaF solutions. Four different pH: 4.0, 5.0, 6.0 and 7.0 were used. Next, SMH test was again used to determine the surface microhardness percentage change (%SMH). Data obtained for %SMH were homogeneous and passed through variance analyses and Tukey's test (5%) as far as fluoride concentrations and pH. Results: The results showed that pH influenced %SMH in 0.02% NaF and 0.05% NaF solutions with pH 4.0, which had less mineral loss compared to pH 7.0 (p<0.05). The 0.02% NaF - pH 4.0, and 0.05% NaF – pH 7.0 groups showed similar results (p>0.05). A dose-response relationship was observed among the tested solutions, with better anticariogenic effect for the 0.1% NaF solution. Conclusion: The results suggest that the addition of citric acid to acidulate mouth rinses reduce mineral loss.

Effect of different solutions on knoop hardness of indirect composite

Introduction: Indirect dental composites may have adequate clinical performance. However, the literature is scarce regarding indirect composite resins and these solutions should be considered to maintain their properties. The aim of the study was to evaluate the influence of beverages, mouthwashes and bleaching agents on the hardness of indirect composite resins. Methods: Five different brands of indirect composite resins were evaluated: Adoro, Resilab, Cristobal, Sinfony and Epricord. Ten specimens of each brand were immersed in eleven different solutions: four mouthwashes (Listerine, Oral-B, Plax, Periogard), four beverages (coke soft drink, red wine, coffee, orange juice), three dental bleaching agents (16% peroxide of carbamide, 7.5% and 38% peroxide of hydrogen) and artificial saliva (control group). The Knoop hardness was measured before (baseline) and after 12, 24, 36 and 60 hours of immersion in mouthwashes; after 7, 14 and 21 days of immersion in beverages and after 7 and 14 days of immersion in dental bleaching agents. The results were analyzed using 3-way repeated measures ANOVA and Tukey’s test (p<0.05). Results: All resins presented significant decrease on hardness values after immersion process whereas this reduction was higher for Resilab and Sinfony. The latter exhibited the lowest initial values of hardness while Cristobol resin presented the highest hardness values. The mouthwashes promoted a significant decrease in the hardness of specimens.

Confining solutions of massive spin-0 bosons by a linear nonminimal vector coupling in the Duffin-Kemmer-Petiau theory

The Duffin-Kemmer-Petiau (DKP) equation, in the scalar sector of the theory and with a linear nominimal vector potential, is mapped into the nonrelativistic harmonic oscillator problem. The behavior of the solutions for this sort of vector DKP oscillator is discussed in detail.

In vitro antibacterial action of Tetraclean, MTAD and five experimental irrigation solutions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antibacterial efficacy of endodontic irrigating solutions and their combinations in root canals contaminated with Enterococcus faecalis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Penetration into dentin of sodium hypochlorite associated with acid solutions

Objective. The objective of this study was to evaluate the penetration of 2.5% NaOCl associated with 17.0% EDTA, 1.0% citric acid, and 1.0% peracetic acid into dentin tubules.Study design. The roots of 44 bovine incisors were cross-sectioned and 5-mm-long fragments were produced from their middle thirds. The specimens were instrumented with ProTaper hand files, stained in crystal violet, then sectioned mesiodistally. The buccal fragments were divided into 4 groups (n = 9) and subjected to 2 consecutive 10-minute immersion periods in one of the following acid solutions combined with 2.5% NaOCl: 17.0% EDTA (group 1), 1.0% citric acid (group 2), and 1.0% peracetic acid (group 3). Nine fragments were immersed in 2.5% NaOCl (group 4). The analysis of the penetration of NaOCl solutions into dentin was performed by measuring the depth of crystal violet stain that was bleached using a steromicroscope under x50 magnification. Statistical comparisons were carried out by Kruskal-Wallis and Dunn's tests at the 5% significance level.Results. Group 1 showed less penetration into dentin than group 4 (P < .05). No statistically significant differences were observed among groups 2, 3, and 4 (P > .05).Conclusions. Association of NaOCl with acid solutions did not increase its penetration depth into root dentin. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;112:e155-e159)

Periodic solutions of abstract neutral functional differential equations

We characterize the existence of periodic solutions of some abstract neutral functional differential equations with finite and infinite delay when the underlying space is a UMD space. (C) 2011 Elsevier B.V. All rights reserved.

Giant monopole resonance and nuclear compression modulus for Ca-40 and O-16

Using a collective potential derived previously on the basis of the generator coordinate method with Skyrme interactions, we obtain values for the compression modulus of Ca-40 which are in good agreement with a recently obtained experimental value. Calculated values for the compression modulus for O-16 are also given. The procedure involved in the derivation of the collective potential is briefly reviewed and discussed.

Asymptotic soliton train solutions of Kaup-Boussinesq equations

Asymptotic soliton trains arising from a 'large and smooth' enough initial pulse are investigated by the use of the quasiclassical quantization method for the case of Kaup-Boussinesq shallow water equations. The parameter varying along the soliton train is determined by the Bohr-Sommerfeld quantization rule which generalizes the usual rule to the case of 'two potentials' h(0)(x) and u(0)(x) representing initial distributions of height and velocity, respectively. The influence of the initial velocity u(0)(x) on the asymptotic stage of the evolution is determined. Excellent agreement of numerical solutions of the Kaup-Boussinesq equations with predictions of the asymptotic theory is found. (C) 2003 Elsevier B.V. All rights reserved.