Effectiveness of a non-fluoridated dentifrice in control of Streptococcus mutans in vitro

Objetivo: avaliar a eficácia de um dentifrício, que contém em sua composição extratos vegetais e xilitol para inibição de Streptococcus mutans (UA159). Materiais e método: para verificação da atividade antimicrobiana, foram realizados ensaios in vitro de difusão de ágar, baseados na metodologia da norma M2A8 Anvisa. O estudo foi feito utilizando inóculo de 108 UFC/mL da cepa de S. mutans. O princípio básico foi a difusão de uma solução de dentifrício na superfície do ágar a partir de um disco impregnado. O ensaio foi realizado utilizando como controle negativo água deionizada estéril e como controle positivo clorexidina 0,12%, e foram comparados aos dentifrícios Orgânico Natural® e Colgate Total 12®. O resultado foi analisado a partir da medição dos halos de inibição (mm). Resultados: a clorexidina 0,12% teve maior halo de inibição (21,08 ± 1,02), seguida do dentifrício Orgânico Natural® (11,33 ± 4,35) e do dentifrício Colgate Total 12 (3,93 ± 4,67) P<0,05. Conclusão: a inibição da cepa de S. mutans evidenciada neste ensaio in vitro demonstra o potencial antimicrobiano do dentifrício Orgânico Natural®, mesmo como um possível auxiliar no controle do biofilme dental cariogênico.Objective: the goal was to evaluate the effectiveness of a dentifrice that has a chemical composition of plant extracts and xylitol to inhibit the Streptococcus mutans (UA159). Materials and methods: based on the methodology of the M2A8 Anvisa standard, in vitro agar diffusion assays were performed to verify antimicrobial activity. The study was carried out using inoculum of 108 CFU / mL of S. mutans strain. The principle was the diffusion of a dentifrice solution on the agar surface, from a disc impregnated therewith. The assay was performed using as a negative control the sterile deionized water, 0.12% chlorhexidine as a positive control compared to Orgânico Natural® and Colgate Total 12® toothpastes. The result was analyzed from the inhibition halos measurement (mm). Results: the chlorhexidine 0.12% had the biggest inhibition halo (21,08 ± 1,02) followed by the Orgânico Natural® dentifrice (11,33 ± 4,35) and the Colgate Total 12® dentifrice (3,93 ± 4,67) P<0,05. Conclusion: the inhibition of the S. mutans strain realized in these in vitro assay by the Orgânico Natural® dentifrice demonstrate the antimicrobial potential of the same as a possible aid in the control of the cariogenic dental biofilm

Analysis of the effectiveness of whitening dentifrices and their effects on the dental surface : an in vitro study

O clareamento dos dentes pode ser realizado de várias maneiras, em consultório, no âmbito caseiro ou com a utilização de produtos OTC (Over-the-Counter). Dentre esses produtos, existem os dentifrícios clareadores que prometem clarear e prevenir o manchamento dentário. Objetivos: (1) Investigar o potencial clareador e abrasivo de diferentes dentifrícios no esmalte; e (2) avaliar o efeito do dentifrício Oral-B 3D White Perfection® (Oral-B) na prevenção do escurecimento. Materiais e Métodos: Amostras de esmalte bovino foram pigmentadas e escovadas por 14 dias com água (controle negativo) ou com diferentes produtos: Colgate Total 12® (controle), Oral-B, Sensodyne Branqueador Extra Fresh® (Sensodyne) ou Colgate Luminous White Advanced® (Colgate). Oral-B foi testado antes e após pigmentação. As amostras foram avaliadas quanto à cor (espectrofotômetro) e rugosidade superficial (rugosímetro). Para cálculo de alteração de cor (ΔDE00) se utilizou o sistema CIEDE2000. Os dados foram analisados com os testes Kruskal-Wallis, SNK e Mann-Whitney (α=5%). Resultados: O controle negativo apresentou a menor ΔE00 (p<0,05) e o grupo tratado com Sensodyne resultou nos maiores valores (p<0,05). Quanto à rugosidade superficial, não houve diferença significativa entre os grupos avaliados. O dentifrício Oral-B demonstrou efeito protetivo ao manchamento, resultando em menor alteração de cor (p=0,002). Conclusão: Somente o dentifrício Sensodyne apresentou potencial clareador maior que o dentifrício convencional. A escovação prévia com Oral-B reduziu o manchamento dental, embora não tenha prevenido este totalmente de acontecer. Não foram observadas alterações significativas na rugosidade dos dentes após aplicação dos tratamentos, quando comparado ao controle.Tooth whitening can be performed at the dental office, at-home or upon the use of OTC (Over-the-Counter) products. Among the latter, there are whitening toothpastes that promise to bleach and to prevent tooth staining. Objectives: (1) To investigate the bleaching and abrasive potential of different whitening dentifrices to enamel; and (2) to evaluate the effect of Oral-B 3D White Perfection® (Oral-B) toothpaste in preventing staining. Materials and Methods: Bovine enamel samples were stained and brushed for 14 days with water (negative control) or with different products: Colgate Total 12® (control), Oral-B, Sensodyne Branqueador Extra Fresh® (Sensodyne), and Colgate Luminous White Advanced® (Colgate). Oral-B was also tested before and after staining. The samples were tested by their color (spectrophotometer) and surface roughness (profilometer). Color change (ΔDE00) was calculated using the CIEDE2000 color system. The data were analyzed using Kruskal-Wallis, SNK, and Mann-Whitney tests (α=5%). Results: The negative control showed the lowest ΔE00 (p<0.05), whereas the group treated with Sensodyne resulted in the greatest color change (p<0.05). For surface roughness, there was not any significant difference among the groups. The Oral-B toothpaste showed a protective effect against staining, resulting in the lowest color change (p=0,002). Conclusion: Only Sensodyne toothpaste showed higher whitening potential than the conventional toothpaste. By using Oral-B prior staining reduced significantly the intensity of staining, although without the complete prevention of this event. Significant differences were not observed after treatment concerning roughness in comparison to the control

Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions

We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

Forward-central two-particle correlations in p-Pb collisions at root s(NN)=5.02 TeV

Two-particle angular correlations between trigger particles in the forward pseudorapidity range (2.5 2GeV/c. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B. V.Peer reviewe

Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at root(NN)-N-S=2.76 TeV

Peer reviewe