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1.
Int. j. high dilution res ; 21(2): 15-16, May 6, 2022.
Artigo em Inglês | LILACS, HomeoIndex - Homeopatia | ID: biblio-1396738

RESUMO

Conventional science regards the study of UHD (highly homeopathically potentized) solutions as pseudo-science. However, an increasing number of rigorous scientific investigations demonstrate differences in physicochemical and physical characteristics of such solutions. Strictly chemically regarded, they correspond to highly distilled water. Our research team developed a system of physicochemical and UV spectrographic measurements, whereby the differences may be consistently confirmed with high statistical significance.Methods:For measurement of the physicochemical parameters,we usedpH,electrical conductivity,and oxidation-reduction potential (ORP)sensors.For UV/VIS spectroscopymeasurements,we useda Macherey-Nagelspectrophotometer.For UHD research, we used two batches of substances: Russian (R) and Brazilian (B). In R, distilled water (W) was used for dilutions and potencies as follows: potentized water (W cH9), potentized dilution of antibodies to interferon-gamma (Abs IFNγ cH9), the same original substance in the form of a mixture of potencies (Abs IFNγ cH12, cH30, cH50, shortly Abs IFNγ mix). Furthermore, we prepared higher potencies of the substances (supplementary potentiation) in a specially prepared solution and measured their characteristics. In B, the solution was used for further dilutions and potencies as follows: potentized water (W cH1) and Glyphosate potencies (Gly cH6 => cH8, cH30 => cH 32, and cH200 => cH 202).For direct or post-hoc analysis, we used Wilcoxon signed-rank test, two-tailed.Results:UV-VIS spectroscopy (R): measurements of received liquids potentized for further cH1 show statistically significant differences between all substances, except between water W and W cH9 at 260 nm. Significant differences (p-values) were as follows: Abs IFNγ mixvs. W= 0.007; Abs IFNγ mixvs.W cH9=0.008; Abs IFNγ cH9vs. W=0.044; Abs IFNγ cH9vs.W cH9= 0.026; Abs IFNγ mixvs.W cH9= 0.007; W vs.W cH9= 0.506.Physicochemical measurements:R: measurementsdemonstrated statistical difference only in pH (Abs IFNγ mix towards all others). Significant differences (p-values) were as follows: Abs IFNγ mixvs. W=0.022; Abs IFNγ mixvs.W cH9=0.005; Abs IFNγ mixvs.Abs IFNγ cH9=0.025. After supplementarypotentiation, we obtained a more conspicuous picture with many statistical differences in conductivity and ORP, ranging from p= 0.001 to 0.046.A difference between water and potentized water has also been demonstrated.B: the measurements demonstrated statistical differences mainly in pH between Gly cH8 and the rest and between Gly cH202 and W cH1.Significant differences (p-values) were as follows:Gly cH8vs. Gly cH32 =0.027; Gly cH8vs. Gly cH202 = 0.011; Gly cH8vs. W cH1= 0.014; Gly cH202vs. W cH1= 0.034.Conclusion:UV/VIS at wavelength 260 nm Abs IFNγ mix discloses a pattern similar to exclusion zone (EZ)water at 270 nm.By additional potentiation and with physicochemical measurements, we obtained higher statistical differences than in the original dilutions.In contrast, UV/VIS spectroscopy showed more conspicuous results without additional potentiation. However, the very act of succussion becomes very distinct


Assuntos
Água/análise , Potência , Fenômenos Químicos , Espectroscopia Fotoeletrônica
2.
Braz. oral res. (Online) ; 33(supl.1): e065, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039317

RESUMO

Abstract Additive manufacturing (AM) is an emerging process for biomaterials and medical devices. Direct Laser Metal Sintering (DLMS) is an AM technique used to fabricate Ti-6Al-4V implant materials with enhanced surface-related properties compared with wrought samples; thus, this technique could influence microbial adsorption and colonization. Therefore, this in vitro study was conducted to evaluate the impact of different implant production processes on microbial adhesion of periodontal pathogens. Titanium discs produced using two different processes—conventional and AM—were divided into three groups: conventional titanium discs with machined surface (G1), AM titanium discs with chemical treatment (G2) and AM titanium discs without chemical treatment (G3). Subgingival biofilm composed of 32 species was formed on the titanium discs, and positioned vertically in 96-well plates, for 7 days. The proportions of microbial complexes and the microbial profiles were analyzed using a DNA-DNA hybridization technique, and data were evaluated using Kruskal-Wallis and Dunnett tests (p < 0.05). Lower proportions of the red complex species were observed in the biofilm formed in G2 compared with that in G1 (p < 0.05). Moreover, the proportions of the microbial complexes were similar between G2 and G3 (p > 0.05). Compared with G1, G2 showed reduced levels of Porphyromonas gingvalis , Actinomyces gerencseriae, and Streptococcus intermedius , and increased levels of Parvimonas micra , Actinomyces odontolyticus, and Eikenella corrodens (p < 0.05). The microbial profile of G3 did not differ from G1 and G2 (p > 0.05). The results of this in vitro study showed that titanium discs produced via AM could alter the microbial profile of the biofilm formed around them. Further clinical studies should be conducted to confirm these findings.


Assuntos
Titânio/farmacologia , Titânio/química , Biofilmes/crescimento & desenvolvimento , Valores de Referência , Propriedades de Superfície , Fatores de Tempo , Bactérias/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Sondas de DNA , Reprodutibilidade dos Testes , Análise de Variância , Estatísticas não Paramétricas , Microscopia de Força Atômica , Biofilmes/efeitos dos fármacos , Espectroscopia Fotoeletrônica
3.
J. appl. oral sci ; 23(6): 614-622, Nov.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: lil-769822

RESUMO

ABSTRACT Plasma technology has the potential to improve the adherence of fibers to polymeric matrices, and there are prospects for its application in dentistry to reinforce the dental particulate composite. Objectives This study aimed to investigate the effect of oxygen or argon plasma treatment on polyethylene fibers. Material and Methods Connect, Construct, InFibra, and InFibra treated with oxygen or argon plasma were topographically evaluated by scanning electron microscopy (SEM), and chemically by X-ray photoelectron spectroscopy (XPS). For bending analysis, one indirect composite (Signum) was reinforced with polyethylene fiber (Connect, Construct, or InFibra). The InFibra fiber was subjected to three different treatments: (1) single application of silane, (2) oxygen or argon plasma for 1 or 3 min, (3) oxygen or argon plasma and subsequent application of silane. The samples (25x2x2 mm), 6 unreinforced and 60 reinforced with fibers, were subjected to three-point loading tests to obtain their flexural strength and deflection. The results were statistically analyzed with ANOVA and the Bonferroni correction for multiple comparison tests. Results SEM analysis showed that oxygen and argon plasma treatments promote roughness on the polyethylene fiber surface. X-ray photoelectron spectroscopy (XPS) analysis shows that both plasmas were effective in incorporating oxygenated functional groups. Argon or oxygen plasma treatment affected the flexural strength and deflection of a fiber reinforced composite. The application of silane does not promote an increase in the flexural strength of the reinforced composites. Conclusions Oxygen and argon plasma treatments were effective in incorporating oxygenated functional groups and surface roughness. The highest strength values were obtained in the group reinforced with polyethylene fibers treated with oxygen plasma for 3 min.


Assuntos
Argônio/química , Oxigênio/química , Plasma/química , Polietileno/química , Análise de Variância , Resinas Compostas/química , Colagem Dentária/métodos , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Maleabilidade , Valores de Referência , Silanos/química , Propriedades de Superfície , Fatores de Tempo
4.
J. appl. oral sci ; 23(3): 279-287, May-Jun/2015. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: lil-752437

RESUMO

Objective The objective of this study was to investigate the impact of two different commercially available dental implants on osseointegration. The surfaces were sandblasting and acid etching (Group 1) and sandblasting and acid etching, then maintained in an isotonic solution of 0.9% sodium chloride (Group 2). Material and Methods X-ray photoelectron spectroscopy (XPS) was employed for surface chemistry analysis. Surface morphology and topography was investigated by scanning electron microscopy (SEM) and confocal microscopy (CM), respectively. Contact angle analysis (CAA) was employed for wetting evaluation. Bone-implant-contact (BIC) and bone area fraction occupied (BAFO) analysis were performed on thin sections (30 μm) 14 and 28 days after the installation of 10 implants from each group (n=20) in rabbits' tibias. Statistical analysis was performed by ANOVA at the 95% level of significance considering implantation time and implant surface as independent variables. Results Group 2 showed 3-fold less carbon on the surface and a markedly enhanced hydrophilicity compared to Group 1 but a similar surface roughness (p>0.05). BIC and BAFO levels in Group 2 at 14 days were similar to those in Group 1 at 28 days. After 28 days of installation, BIC and BAFO measurements of Group 2 were approximately 1.5-fold greater than in Group 1 (p<0.05). Conclusion The surface chemistry and wettability implants of Group 2 accelerate osseointegration and increase the area of the bone-to-implant interface when compared to those of Group 1. .


Assuntos
Animais , Masculino , Feminino , Coelhos , Implantação Dentária Endóssea/métodos , Implantes Dentários , Osseointegração/efeitos dos fármacos , Osseointegração/fisiologia , Titânio/química , Condicionamento Ácido do Dente , Materiais Biocompatíveis , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Valores de Referência , Propriedades de Superfície/efeitos dos fármacos , Tíbia/efeitos dos fármacos , Fatores de Tempo , Molhabilidade
5.
J. appl. oral sci ; 21(4): 300-306, Jul-Aug/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-684566

RESUMO

OBJECTIVE: This study investigated the effects of different surface treatments on the tensile bond strength of an autopolymerizing silicone denture liner to a denture base material after thermocycling. MATERIAL AND METHODS: Fifty rectangular heat-polymerized acrylic resin (QC-20) specimens consisting of a set of 2 acrylic blocks were used in the tensile test. Specimens were divided into 5 test groups (n=10) according to the bonding surface treatment as follows: Group A, adhesive treatment (Ufi Gel P adhesive) (control); Group S, sandblasting using 50-µm Al2O3; Group SCSIL, silica coating using 30-µm Al2O3 modified by silica and silanized with silane agent (CoJet System); Group SCA, silica coating and adhesive application; Group SCSILA, silica coating, silane and adhesive treatment. The 2 PMMA blocks were placed into molds and the soft lining materials (Ufi Gel P) were packed into the space and polymerized. All specimens were thermocycled (5,000 cycles) before the tensile test. Bond strength data were analyzed using 1-way ANOVA and Duncan tests. Fracture surfaces were observed by scanning electron microscopy. X-ray photoelectron spectrometer (XPS) and Fourier Transform Infrared spectrometer (FTIR) analysis were used for the chemical analysis and a profilometer was used for the roughness of the sample surfaces. RESULTS: The highest bond strength test value was observed for Group A (1.35±0.13); the lowest value was for Group S (0.28±0.07) and Group SCSIL (0.34±0.03). Mixed and cohesive type failures were seen in Group A, SCA and SCSILA. Group ...


Assuntos
Bases de Dentadura , Reembasadores de Dentadura , Colagem Dentária/métodos , Materiais Dentários/química , Silanos/química , Dióxido de Silício/química , Análise de Variância , Análise do Estresse Dentário , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Polimerização/efeitos dos fármacos , Reprodutibilidade dos Testes , Propriedades de Superfície , Resistência à Tração
6.
Int. j. odontostomatol. (Print) ; 6(3): 355-361, 2012. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-676199

RESUMO

El objetivo de este estudio fue analizar la composición química y la topografía superficial de implantes de titanio comercialmente puro, obtenidos de 3 marcas comerciales utilizadas actualmente en odontología. Fueron analizados 6 implantes de titanio de los siguientes sistemas: SIN, P-I philosophy y Neodent. Este material fue dividido en 3 grupos de 3 implantes cada uno. Para determinar la composición química de la superficie fue utilizada la técnica de Espectroscopia de Fotoelectrones Excitada por rayos-X (XPS), mientras que para caracterizar la topografía superficial fue utilizada Microscopia electrónica de barrido. Titanio, Carbono Silicio y Oxigeno fueron identificados en todas las muestras analizadas. Otros elementos contaminantes identificados fueron Silicio, Aluminio, azufre, plomo, Fósforo, Calcio, Sodio, Nitrógeno y Carbono. Fueron identificadas impurezas en la superficie de todos los implantes analizados. Consideramos necesarios otros estudios que relacionen permanentemente la presencia y concentración de estos elementos con el proceso de oseointegración...


The aim of this study was to analyze the chemical composition and surface topography of commercially pure titanium implants, obtained from 03 trademarks frequently used in dentistry. There were 9 titanium implants of the following systems: SIN, P-I philosophy and Neodent. These materials were divided into 3 groups, with 3 implants in each group. Photoelectron Spectroscopy Excited by X-ray (XPS) was used to determine the chemical composition, while to characterize the surface topography we used Scanning Electron Microscopy (SEM). Titanium, carbon silicon and oxygen were identified in all samples analyzed. Other contaminants were: silicon, aluminum, sulfur, lead, phosphorus, calcium, sodium, nitrogen and carbon. We identified impurities on the surface of all implants analyzed. We consider necessary to development more studies relating the presence and concentration of these elements with the osseointegration process...


Assuntos
Humanos , Implantes Dentários , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Titânio/química , Propriedades de Superfície
7.
Braz. dent. j ; 21(1): 3-11, Jan. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-552348

RESUMO

The aims of this study were to characterize the microstructure of a commercially pure titanium (cpTi) surface etched with HCl/H2SO4 (AE-cpTi) and to investigate its in vitro cytocompatibility compared to turned cpTi (T-cpTi). T-cpTi showed a grooved surface and AE-cpTi revealed a surface characterized by the presence of micropits. Surface parameters indicated that the AE-cpTi surface is more isotropic and present a greater area compared to T-cpTi. The oxide film thickness was similar between both surfaces; however, AE-cpTi presented more Ti and O and less C. Osteoblastic cell proliferation, alkaline phosphatase activity, and bone-like nodule formation were greater on T-cpTi than on AE-cpTi. These results show that acid etching treatment produced a surface with different topographical and chemical features compared to the turned one, and such surface modification affected negatively the in vitro cytocompatibility of cpTi as demonstrated by decreasing culture growth and expression of osteoblastic phenotype.


O objetivo deste estudo foi caracterizar a microestrutura de uma superfície de titânio comercialmente puro (cpTi) condicionada com HCl/H2SO4 (acid etched) (AE-cpTi) e investigar sua citocompatibilidade in vitro, comparada à do cpTi usinado (turned) (T-cpTi). O T-cpTi apresentou uma superfície com sulcos e o AE-cpTi exibiu uma superfície caracterizada pela presença de micro-vales. Os parâmetros de superfície indicaram que a superfície AE-cpTi é mais isotrópica e apresenta uma área maior quando comparada à superfície T-cpTi. A espessura da camada de óxido foi similar para as duas superfícies; no entanto, a AE-cpTi apresentou maiores quantidades de Ti e O e menor, de C. A proliferação de células osteoblásticas, a atividade de fosfatase alcalina e a formação de matriz mineralizada foram maiores na superfície T-cpTi que na AE-cpTi. Esses resultados mostram que o condicionamento ácido produziu uma superfície com características topográficas e químicas diferentes quando comparadas às da superfície usinada. Além disso, observou-se que essas modificações de superfície afetaram de forma negativa a citocompatibilidade in vitro do cpTi como demonstrado pela inibição da proliferação celular e da expressão do fenótipo osteoblástico.


Assuntos
Humanos , Condicionamento Ácido do Dente , Materiais Biocompatíveis/farmacologia , Materiais Dentários/farmacologia , Osteoblastos/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/análise , Processo Alveolar/citologia , Materiais Biocompatíveis/química , Biomarcadores/análise , Células Cultivadas , Carbono/química , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Materiais Dentários/química , Ácido Clorídrico/química , Interferometria , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteogênese/efeitos dos fármacos , Fenótipo , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Ácidos Sulfúricos/química , Titânio/química
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