Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 112
Filtrar
1.
Int. j. morphol ; 41(3): 699-704, jun. 2023. tab
Artigo em Inglês | LILACS | ID: biblio-1514323

RESUMO

SUMMARY: One of the most important minimally invasive treatments today in temporomandibular joint osteoarthritis (TMJ- OA) is the intra-articular exogenous hyaluronic acid (HA) injection, which has yielded good results in pain relief and improves mandibular function with few side effects. However, the effectiveness of HA continues to be controversial, partly due to the heterogeneity in the injection protocols in their molecular weight, viscosity and frequency of infiltration, among other properties. The aim of this review is to identify the differences in the histological and clinical effects of the different types of HA and the frequency of infiltration on TMJ-OA treatment. Materials and methods: A bibliographic search was performed in the PubMed, Web of Science and Scopus databases. The search was limited up to September 2022. Search terms included "osteoarthritis", "hyaluronic acid, "molecular weight", "concentration", "viscosity", "dose" and "temporomandibular", using AND/OR as Boolean terms. Results: Exogenous HA in its different molecular weights offers an improvement in histological and clinical characteristics. Apparently, low and medium molecular weight HA presents better results. No clinical studies related to the degree of HA viscosity were found. Respect to the frequency of infiltration, single injection, weekly injections for 3 weeks, weekly injections for 5 weeks and other protocols are used. However, their comparison is complex. There seems to be differences in the effects of the different HA preparations for the treatment of TMJ-OA, mainly in their molecular weight. However, the evidence remains scant.


Uno de los tratamientos mínimamente invasivos más importantes en la actualidad en la artrosis de la articulación temporomandibular (OATM) es la inyección intraarticular de ácido hialurónico (AH) exógeno, que ha dado buenos resultados en el alivio del dolor y mejora la función mandibular con pocos efectos secundarios. Sin embargo, la efectividad del AH continúa siendo controversial, en parte debido a la heterogeneidad en los protocolos de inyección en cuanto a su peso molecular, viscosidad y frecuencia de infiltración, entre otras propiedades. El objetivo de esta revisión fue identificar las diferencias en los efectos histológicos y clínicos de los diferentes tipos de HA y la frecuencia de infiltración en el tratamiento de TMJ-OA. Se realizó una búsqueda bibliográfica en las bases de datos PubMed, Web of Science y Scopus. La búsqueda se limitó hasta septiembre de 2022. Los términos de búsqueda incluyeron "osteoartritis", "ácido hialurónico", "peso molecular", "concentración", "viscosidad", "dosis" y "temporomandibular", utilizando AND/OR como términos booleanos. El HA exógeno en sus diferentes pesos moleculares ofrece una mejora en las características histológicas y clínicas. Aparentemente, el AH de bajo y medio peso molecular presenta mejores resultados. No se encontraron estudios clínicos relacionados con el grado de viscosidad del HA. Respecto a la frecuencia de infiltración, se utilizan inyecciones únicas, inyecciones semanales durante 3 semanas, inyecciones semanales durante 5 semanas y otros protocolos. Sin embargo, su comparación es compleja. Parece haber diferencias en los efectos de las diferentes preparaciones de HA para el tratamiento de la OA-TMJ, principalmente en su peso molecular. Sin embargo, la evidencia sigue siendo escasa.


Assuntos
Humanos , Osteoartrite/tratamento farmacológico , Transtornos da Articulação Temporomandibular/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Viscosidade/efeitos dos fármacos , Injeções , Peso Molecular
2.
Int. j. morphol ; 40(3): 824-831, jun. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1385651

RESUMO

SUMMARY: Biomechanical factors are important factors in inducing intervertebral disc degeneration, in this paper, the nonlinear viscoelastic mechanical properties of degenerated intervertebral discs were analyzed experimentally. Firstly, the loading and unloading curves of intervertebral discs before and after degeneration at different strain rates were compared to analyze the changes of their apparent viscoelastic mechanical properties; The internal stress/strain distribution of the disc before and after degeneration was then tested by combining digital image technology and fiber grating technology. The results show that the intervertebral disc is strain-rate- dependent whether before or after degeneration; The modulus of elasticity and peak stress of the degenerated disc are significantly reduced, with the modulus of elasticity dropping to 50 % of the normal value and the peak stress decreasing by about 55 %; Degeneration will not change the distribution of the overall internal displacement of the intervertebral disc, but has a greater impact on the superficial and middle AF; The stress in the center of the nucleus pulposus decreases, and the stress in the outer AF increases after degeneration. Degeneration has a great impact on the nonlinear viscoelastic mechanical properties of intervertebral disc, which has reference value for the mechanism, treatment and prevention of clinical degenerative diseases.


RESUMEN: Los factores biomecánicos son importantes en la inducción de la degeneración del disco intervertebral. En este estudio se analizaron experimentalmente las propiedades mecánicas viscoelásticas no lineales de los discos intervertebrales degenerados. En primer lugar se compararon las curvas de carga y descarga de los discos intervertebrales, antes y después de la degeneración, a diferentes velocidades de deformación para analizar los cambios aparentes de sus propiedades mecánicas viscoelásticas. La distribución interna de tensión/deformación del disco antes y después de la degeneración se probó luego combinando tecnología de imagen digital y tecnología de rejilla de fibra. Los resultados mostraron que el disco intervertebral depende de la velocidad de deformación antes o después de la degeneración; El módulo de elasticidad y la tensión máxima del disco degenerado se reducen significativamente, cayendo el módulo de elasticidad al 50 % del valor normal y la tensión máxima disminuyendo en aproximadamente un 55 %; La degeneración no cambiará la distribución del desplazamiento interno general del disco intervertebral, pero tiene un mayor impacto en la FA superficial y media; El estrés en el centro del núcleo pulposo disminuye y el estrés en el FA externo aumenta después de la degeneración. La degeneración tiene un gran impacto en las propiedades mecánicas viscoelásticas no lineales del disco intervertebral, que tiene valor de referencia para el mecanismo, tratamiento y prevención de enfermedades clínicas degenerativas.


Assuntos
Estresse Mecânico , Viscosidade , Dinâmica não Linear , Degeneração do Disco Intervertebral , Fenômenos Biomecânicos , Módulo de Elasticidade , Modelos Biológicos
3.
Vitae (Medellín) ; 29(2): 1-8, 2022-05-19. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1393172

RESUMO

Background: Lactic fermentations are a catabolic process in which biochemical transformations of different organic products occur. Sugars are mainly converted into organic acids, increasing viscosity, acid taste, aroma, and flavor. Lactic acid bacteria provide probiotic characteristics if they reach counts of 106 CFU*g-1 (Colony Forming Units) in the final product, which can generate wellness for consumers. Objective: This research aimed to compare the lactic fermentation process in three substrates using two commercial cultures. Methods: Whole milk (control), aqueous extract of oats flakes, and an aqueous extract of a mixture of oats flakes with mashua pulp were used. The whole milk was heated, and the aqueous extracts were prepared. All samples were divided into two parts, keeping the temperature at 42°C, and then inoculated with Yomix y Choozit. Each the fermentation lasted 6 hours at 42°C. Fermentation samples were taken each hour, and pH, titratable acidity. and Brix degrees were determined. Results: Total lactic acid bacteria were counted at the end of each fermentation. The final product was evaluated with sensory analysis. As expected, there was an increase in titratable acidity, and a decreased pH and Brix degrees. It was observed that the dairy product showed the most significant changes. Fermentations performed with Yomix presented a higher count of lactic bacteria. Conclusion: It is possible to carry out lactic fermentation using substrates that do not contain milk, requiring higher initial soluble solids and a longer incubation time


Antecedentes: Las fermentaciones lácticas son un proceso catabólico en el que ocurren transformaciones bioquímicas de diferentes productos orgánicos. En ellas, los azúcares son convertidos principalmente en ácidos orgánicos, generando adicionalmente el aumento de viscosidad, sabor ácido, aromas y sabores en los productos finales. Adicionalmente, aportan características probióticas, ya que son realizadas por bacterias lácticas, que, si alcanzan recuentos de 106 UFC*g-1 (Unidades formadoras de colonias) en el producto final, generan bienestar para los consumidores. Objetivo: Esta investigación tuvo como objetivo comparar el proceso de fermentación láctica en tres sustratos utilizando dos cultivos comerciales. Métodos: Se utilizó leche entera (control), extracto acuoso de hojuelas de avena y un extracto acuoso de mezcla de hojuelas de avena con pulpa de cubios. Se llevó a cabo el calentamiento de la leche entera, y la preparación de los sustratos de avena y cubios. Dichas muestras se dividieron en dos partes, manteniendo la temperatura a 42°C. Cada una de las muestras fue inoculada con Yomix y Choozit. Cada fermentación duró 6 horas manteniendo una temperatura de 42°C. Durante cada hora se tomaron muestras, a las cuales se evaluó el pH, acidez titulable y grados brix. En los productos finales se realizó el recuento de bacterias lácticas y se realizó una evaluación sensorial. Resultados: A lo largo de la fermentación se presentó el aumento de la acidez titulable, y disminución del pH y los grados Brix. Se observó que el producto a base de leche mostró los cambios más significativos. En el caso de los productos obtenidos usando Yomix, presentaron mayor recuento de bacterias lácticas al ser comparados con aquellos en los que se usó el cultivo 1. Conclusión: Es posible realizar la fermentación láctica usando sustratos que no contengan leche, los cuales requieren mayores sólidos solubles iníciales y un mayor tiempo de incubación


Assuntos
Avena , Leite , Fermentação , Tecnologia de Alimentos/métodos , Paladar , Viscosidade
4.
Braz. dent. sci ; 25(4): 1-13, 2022. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1400962

RESUMO

Objetivo: Este ensaio clínico randomizado, duplo-cego e boca dividida avaliou o desempenho clínico de um novo compósito termoviscoso com pré-aquecimento (PHT) em comparação com uma resina composta sem aquecimento (NHT) em restaurações de lesões cervicais não cariosas (LCNCs) durante um período de 6 meses. Material e Métodos: 120 restaurações foram realizadas em LCNCs com dois materiais restauradores (n = 60). Após a profilaxia, os dentes foram isolados com isolamento de fio retrator/rolos de algodão e um adesivo universal foi aplicado na estratégia de condicionamento seletivo do esmalte. Para o grupo PHT o aquecimento foi realizado a 68°C usando um aquecidor de bancada por 3 min. Por outro lado, para o grupo NHT, nenhum aquecimento foi aplicado. Ambos os materiais restauradores foram colocados no dispensador de cápsulas e inseridos nas LCNCs. Após 6 meses, o desempenho clínico das restaurações foi avaliado de acordo com os critérios FDI. A análise estatística foi realizada com teste Qui-quadrado para todos parâmetros da FDI (α = 0,05). Resultados: Apenas três restaurações no grupo NHT foram perdidas/fraturadas após seis meses de acompanhamento. As taxas de retenção (intervalo confiança 95%) por seis meses foram de 97,5% (88,6% - 99,0%) para o grupo NHT e 100% (93,9% - 100%) para o grupo PHT (p > 0,05). Vinte e duas restaurações (8 para NHT e 14 para PHT) apresentaram pequenos defeitos de adaptação marginal aos seis meses de acompanhamento (p > 0,05). Vinte e seis restaurações apresentaram alguma retenção de biofilme aos seis meses de acompanhamento (11 para NHT e 15 para PHT; p > 0,05). Em relação a todos os outros parâmetros de FDI avaliados, todas as restaurações foram consideradas clinicamente aceitáveis. Conclusão: O desempenho clínico do novo compósito termoviscoso de pré-aquecimento mostrou-se promissor após 6 meses de avaliação clínica quando aplicado em LCNCs.(AU)


Objective: This double-blind, split-mouth randomized clinical trial evaluate the clinical performance of a new preheating (PHT) thermoviscous composite compared to a non-heating (NHT) composite resin in restorations of non-carious cervical lesions (NCCLs) over a period of 6-month. Material and Methods: 120 restorations were performed on NCCLs with two restorative materials (n = 60). After prophylaxis, the teeth were isolated with retraction cord isolation/cotton rolls and one universal adhesive was applied in the selective enamel etching strategy. For the PHT group heating was carried out at 68°C using a heater bench for 3 min. On the other side, for the NHT group, no heating was applied. Both restorative materials were placed in the caps dispenser and inserted in the NCCLs. The restorations were evaluated after 6-month of clinical performance according to the FDI criteria. Statistical analysis was performed with Chi-square test for all FDI parameters (α = 0.05). Results: Three restorations only in the NHT group were lost/fractured after six months follow-up. The retention rates (confidential interval 95%) for six months were 97.5% (88.6% - 99.0%) for the NHT group and 100% (93.9% - 100%) for the PHT group (p > 0.05). Twenty-two restorations (8 for NHT and 14 for PHT) presented small marginal adaptation defects at the six-months follow-up (p > 0.05). Twenty-six restorations were found to have biofilm retention in the six-month recall (11 for NHT and 15 for PHT; p > 0.05). Regarding all others FDI parameters evaluated, all restorations were considered clinically acceptable. Conclusion: The clinical performance of the new preheating thermoviscous was found to be promise after 6-month of clinical evaluation when applied in NCCLs (AU)


Assuntos
Temperatura , Viscosidade , Ensaio Clínico , Resinas Compostas
5.
Braz. j. biol ; 81(1): 1-10, Feb. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153324

RESUMO

Abstract Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.


Resumo Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.


Assuntos
Amilose , Fabaceae , Amido , Viscosidade , Camarões
6.
Revista Areté ; 21(1): 33-41, 2021. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1354622

RESUMO

La iniciativa internacional para la estandarización de la dieta de disfagia (IDDSI) clasifica la viscosidad de los líquidos por niveles y determina metodologías específicas para evaluar cada consistencia. Con todo, la iniciativa no determina las medidas específicas de espesante requeridas para obtener cada nivel de viscosidad y sugiere hacer adaptaciones de acuerdo con las condiciones particulares de aplicación. Este estudio desarrolló una propuesta para la preparación de viscosidades mediante pruebas experimentales en las que se controló rigurosamente la cantidad de espesante y agua haciendo uso de instrumentos de mezclado de fácil acceso en entornos clínicos (vasos plásticos, jarra de agua, baja lenguas para integrar los elementos y cronómetro para considerar el tiempo de fraguado). Posterior a ello, cada nivel de viscosidad obtenido fue evaluado con el test de flujo propuesto por las IDDSI. Como resultado, este estudio especifica las cantidades necesarias de agua y espesante para conseguir viscosidad en bebidas de 0-4. Los hallazgos presentados, tienen en cuenta factores influyentes como la ubicación geográfica, temperatura y altitud. Se espera que esta propuesta incida en las dinámicas de evaluación de la deglución en el área clínica colombiana de forma que esta sea más precisa y eficaz. Finalmente, es pertinente realizar futuras investigaciones que determinen medidas específicas de espesante para lograr cambios en la viscosidad de líquidos diferentes al agua e igualmente necesario, replicar esta propuesta con otros espesantes de más fácil acceso para los usuarios y que tengan en cuenta otros aspectos como la palatabilidad


The International Dysphagia Diet Standardisation Initiative (IDDSI) classifies the viscosity of liquids by levels and determines specific methods to evaluate each consistency. However, the initiative does not determine the specific measures of thickener required to obtain each level of viscosity and suggests making adaptations according to the particular conditions of application. This study developed a proposal for the preparation of viscosities through experimental tests in which the amount of thickener and water was rigorously controlled using mixing instruments that were easily accessible in clinical settings (plastic cups, pitcher of water, tongue depressors to integrate the elements and timer to consider setting time). After that, each level of viscosity obtained was evaluated with the flow test proposed by the IDDSI. As a result, this study specifies the required amounts of water and thickener to achieve drinks viscosities 0-4. The findings presented take into account influencing factors such as geographic location, temperature and altitude. It is expected that this proposal will affect the dynamics of swallowing assessment in the Colombian clinical area so that it is more precise and effective. Finally, it is pertinent to carry out future investigations that determine specific measures of thickener to achieve changes in the viscosity of liquids other than water and it is equally necessary to replicate this proposal with other thickeners that are easier for users to access and that take into account other aspects such as palatability.


Assuntos
Língua , Transtornos de Deglutição , Deglutição , Padrões de Referência , Viscosidade , Volição , Bebidas , Água , Preparação em Desastres , Dieta , Espessantes
7.
J. appl. oral sci ; 29: e20200609, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1154615

RESUMO

Abstract Objective To compare the effectiveness of ART restorations using High Viscosity Glass-ionomer cement (HVGIC) with conventional restorations using resin composite in Class II cavities of permanent teeth, in a 2-year follow-up. Methodology Seventy-seven restorations were made with each restorative material, Equia Fil-GC Corporation (ART restorations) and Z350-3M (conventional restoration), in 54 participants in this parallel and randomized clinical trial. Restorations were evaluated at 6 months, 1 and 2 years using the ART and the modified United States Public Health Service (USPHS) criteria. Chi-square test and Survival Analysis (p<0.05) were used for statistical analysis. Results The success rates for ART restorations were 98.7% (6 months) and 95.8% (1 year) for both criteria. At 2 years, success rate was 92% and 90.3% when scored by the modified USPHS and ART criteria (p=0.466), respectively. The success rates for conventional restorations were 100% (6 months), 98.7% (1 year) and 91.5% (2 years) for both assessment criteria. ART restorations presented a lower survival rate by the criterion of ART (83.7%) when compared to the modified USPHS criterion of (87.8%), after 2 years (p=0.051). The survival of conventional restorations was 90.7% for both evaluation criteria. Conclusion At the 2-years follow-up evaluation, no statistically significant difference was observed between the success rate of ART restorations with HVGIC compared to conventional restorations with resin composite in Class II cavities of permanent teeth.


Assuntos
Humanos , Cárie Dentária , Cimentos de Ionômeros de Vidro , Viscosidade , Estudos Prospectivos , Seguimentos , Resinas Compostas , Restauração Dentária Permanente
8.
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1143393

RESUMO

ABSTRACT Objective: To evaluate the amount of residual monomers released after polymerization by the compomers in different colors and viscosities over time. Material and Methods: The compomer samples of different colors and viscosities (flowable compomers; blue-pink and packable compomers; A2-blue-pink-gold) were prepared in molds with an inner diameter of 5 mm and a height of 2 mm. In polymerization of samples, a LED unit was used. The amount of monomers released from the samples kept in 75% ethanol/water solution was measured by a high-performance liquid chromatography (HPLC) instrument in the 10th minute, in the 1st hour, and in the 1st, 7th, and 14th days. For statistical analyses, the paired sample t-test, independent sample t-test, and one-way ANOVA with Tukey's post hoc test were used. Results: The amount of residual monomers released from all materials increased over time. At the end of the 14th day, the most released monomer from all compomer samples was BisGMA. The total amounts of released monomers from the packable compomers were Gold>A2>blue>pink. The amount of residual monomers released from flowable compomers was higher in blue than in pink. Conclusion: The color and the viscosity are the factors affecting the residual monomer release in compomers.


Assuntos
Cromatografia/instrumentação , Compômeros , Materiais Dentários , Polimerização , Turquia/epidemiologia , Viscosidade , Análise de Variância , Cromatografia Líquida de Alta Pressão/instrumentação , Estatísticas não Paramétricas
9.
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1143394

RESUMO

ABSTRACT Objective: To analyze the ability of saliva in controlling the growth and the biofilm formation of Streptococcus mutans (S. mutans) as well as the effect of histatin-5 anti-biofilm relate to pH and saliva viscosity. Material and Methods: The S. mutans biofilm assayed by crystal violet 1% and its growth measured by spectrophotometer. The saliva viscosity was analyzed by viscometer, and pH of saliva was measured by pH meter. Results: Based on the optical density values, growth of S. mutans in saliva ranged <300 CFU/mL (0.1 nm) at concentrations of 25%, 12.5% and 6.25% for 24 hours. Whereas at the 48 h and 72 h period of incubation shown an increase in growth of S. mutans ranged 300-600 CFU/mL (0.2-0.36 nm). The inhibitory biofilm formation of S. mutans in saliva was significantly higher at concentrations of 12.5% and 6.25% at 24 h incubation times on a moderate scale, whereas the histatin-5 was effective to inhibit S. mutans biofilm on the 50 and 25 ppm. The saliva possessed a higher inhibitory of biofilm S. mutans than histatin-5 and good level viscosity (0.91-0.92 cP). Conclusion: The saliva was able to control the growth of S. mutans, and histatin-5 can inhibit the biofilm formation S. mutans. Furthermore, the saliva was also able to respond to the pH change with good viscosity of saliva.


Assuntos
Humanos , Masculino , Feminino , Criança , Saliva/microbiologia , Biofilmes , Estreptococos Viridans , Histatinas , Concentração de Íons de Hidrogênio , Espectrofotometria/instrumentação , Streptococcus mutans , Viscosidade , Análise de Variância , Estatísticas não Paramétricas , Indonésia/epidemiologia
10.
Acta odontol. latinoam ; 33(2): 59-68, Sept. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1130735

RESUMO

ABSTRACT The aim of this in vitro study was to evaluate the effect of bleaching protocols on the surface roughness (Ra), color change and surface micromorphology of a low-viscosity bulk-fill composite (Filtek Bulk Fill Flow, 3M ESPE), a highviscosity bulk-fill composite (Filtek Bulk Fill, 3M ESPE) and a conventional nanoparticulate composite resin (control) (Filtek Z350 XT, 3M ESPE). Forty samples of each composite (disks 5 mm in diameter and 2 mm thick) were randomly divided into four groups (n=10), according to bleaching protocol: a) 10% carbamide peroxide gel (Opalescence, Ultradent Products) (2 h/ day, for 14 days); b) 40% hydrogen peroxide gel (Opalescence Boost, Ultradent Products) (three bleaching sessions, once a week, 45 min/session); c) whitening rinse (Listerine Whitening Extreme, Johnson & Johnson) (2 min/day, for 14 days); and d) distilled water (control). The samples were submitted to triplicate readings (Ra and color [CIELAB parameters]) before and after contact with bleaching protocols. Micromorphology was analyzed in a scanning electron microscope (SEM). Ra and color parameters (ΔL, Δa, Δb and ΔE) were analyzed by generalized linear models (α=0.05). The Ra of the high-viscosity bulk-fill was significantly higher than that of the other composites (p<0.05). Ra increased significantly (p<0.05) and surface became more irregular (SEM analysis) in all the composite resins, regardless of the bleaching protocol (p<0.05). The high-viscosity bulk-fill composite resin group had significantly lower ΔE (p<0.05) than the nanoparticulate composite resin group immersed in distilled water. It was concluded that the characteristics of each resin significantly influenced the Ra more than the bleaching protocol. The high-viscosity bulk-fill resin presented minor color change.


RESUMO Este estudo in vitro teve objetivo de avaliar o efeito de protocolos clareadores sobre a rugosidade de superfície (Ra), alteração de cor e micromorfologia de resina bulk-fill de baixa viscosidade (Filtek Bulk Fill Flow, 3M ESPE), alta viscosidade (Filtek Bulk Fill, 3M ESPE) e de uma resina composta nanoparticulada (controle) (Filtek Z350 XT, 3M ESPE). Quarenta amostras de cada resin composta (discos de 5 mm de diâmetro e 2 mm de espessura) foram aleatoriamente divididas em quatro grupos , de acordo com protocolo clareador (n=10): a) Gel de peróxido de carbamida (Opalescence, Ultradent Products) (2 horas/dia, por 14 dias); b) Gel de peróxido de hidrogênio (Opalescence Boost, Ultradent Products) (3 sessões de clareamento, uma por semana, 45 min/sessão); enxaguatório clareador (Listerine Whitening Extreme, Johnson & Johnson) (2 min/dia, por 14 dias); d) água destilada (controle). As amostras foram submetidas a leituras, em triplicata (Ra e cor (parâmetros CIELab) antes e depois do contato com os protocolos clareadores. A micromorfologia de superfície foi conduzida em microscópio eletrônico de varredura (MEV). Ra e parâmetros de cor (ΔL, Δa, Δb e ΔE) foram analisados por modelos lineares generalizados (α=0.05). A Ra da resina bulk-fill de alta viscosidade foi significantemente superior do que para os outros compósitos (pp<0.05). A Ra aumentou significantemente (p<0.05) e a superfície ficou mais irregular (MEV) para todos os compósitos, independente do protocolo clareador (pp<0,05). A resina bulk-fill de alta viscosidade obteve menor ΔE (pp<0.05) do que a resina composta nanoparticulada, imersa em água destilada. Pode-se concluir que as características de cada resina composta influenciaram de forma mais significativa a Ra do que o protocolo clareador. A resina bulk fill de alta viscosidade apresentou menor alteração de cor.


Assuntos
Humanos , Clareamento Dental/métodos , Descoloração de Dente/tratamento farmacológico , Viscosidade/efeitos dos fármacos , Resinas Compostas/química , Clareadores Dentários/química , Peróxido de Hidrogênio/química , Teste de Materiais , Cor
11.
J. oral res. (Impresa) ; 9(2): 98-103, abr. 30, 2020. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1151857

RESUMO

Evaluate the effect of a synbiotic on salivary viscosity and buffer capacity. Materials and Methods: A follow-up one-week study was performed on 24 healthy volunteers in San Luis Potosí, Mexico, during July 2017. Volunteers must have had active tooth decay at the moment of study. All 24 patients were given a Lactiv® probiotic package, advising not to modify usual oral hygiene practices, and were followed up during 6 days. Primary output variable was salivary viscosity while the secondary was salivary buffer capacity. Salivary viscosity was assessed by using an Ostwald Pipette and buffer capacity with bromocresol purple. Results: A total of 8 male patients (33.3%) and 16 females (66.6%) patients were included, with an average age of 10.92 years. All the volunteers completed the study. Comparisons between pre- and post-treatment showed a decrease in salivary viscosity, while buffer capacity was showed to increase. Conclusion: The use of a synbiotic during a short period of time lowered the viscosity of saliva and increased salivary buffer capacity.


Evaluar el efecto de un sinbiótico sobre la viscosidad salival y la capacidad de tampón de la saliva. Materiales and Métodos: Se realizó un estudio de seguimiento de una semana en 24 voluntarios sanos en San Luis Potosí, México, durante julio de 2017. Los voluntarios cursaban caries dental activa en el momento del estudio. Los 24 pacientes recibieron un paquete de probióticos Lactiv®, fueron aconsejados a no modificar las prácticas habituales de higiene oral, y fueron seguidos durante 6 días. La variable primaria fue la viscosidad salival mientras que la secundaria fue la capacidad tampón. La viscosidad salival se evaluó usando una pipeta Ostwald y capacidad tampón con bromocresol púrpura. Resultados: Se incluyeron un total de 8 pacientes varones (33,3%) y 16 mujeres (66,6%), con una edad promedio de 10,92 años. Todos los voluntarios completaron el estudio. Las comparaciones entre el pretratamiento y el postratamiento mostraron una disminución de la viscosidad salival, mientras que se demostró que la capacidad del tampón aumentó. Conclusión: El uso de un sinbiótico durante un corto período de tiempo mostró un efecto sobre la disminución de la viscosidad y el aumento de la capacidad del tampón salival.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Saliva/efeitos dos fármacos , Probióticos/administração & dosagem , Simbióticos , Viscosidade , Resultado do Tratamento , Cárie Dentária , Ensaios Clínicos Controlados não Aleatórios como Assunto , México
13.
Braz. J. Pharm. Sci. (Online) ; 56: e17509, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132046

RESUMO

Amphotericin B is a broad spectrum antifungal agent used to treat fungal infections. Organogel is a semisolid preparation in which the apolar phase gets immobilized within spaces of the three-dimensional structure. The current study aimed at the formulation and comparative evaluation of sorbitan monostearate organogels and pluronic lecithin organogels (PLO). Different compositions of span 60 based organogels were prepared by varying the concentrations of the span 60 and PLO gels were prepared by varying the concentration of Pluronic F 127. The developed organogels were subjected to various characteristics such as pH, viscosity, spreadability, extrudability, and drug release studies. The optimized formulations were evaluated against Candida albicans and carried out ex vivo release study. The optimized formulation was selected from span 60 based organogels, and pluronic lecithin organogels were S1 and P1, respectively. The optimized formulation (S1) showed effective inhibition against Candida albicans. The skin irritation test was carried out on albino mice for optimized formulations and results showed that no irritation to the skin. Based on the results, organogels prepared by sorbitan monostearate showed better antifungal activity, and also all the formulations were found to be stable and safe throughout the study period.


Assuntos
Pele , Candida albicans/classificação , Anfotericina B/agonistas , Crescimento e Desenvolvimento , Antifúngicos/análise , Viscosidade , Liberação Controlada de Fármacos , Micoses/patologia
14.
Braz. oral res. (Online) ; 34: e099, 2020. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1132660

RESUMO

Abstract The composition of infiltrants can influence their physical properties, viscosity and depth of penetration (DP). Strategies are used to increase the DP, such as the addition of diluents or the use of heat. This study aimed to evaluate the effect of preheating and composition on physical properties and DP of infiltrants in demineralized enamel. The groups were assigned, and the following experimental formulations were made: 25%BisEMA +75%TEGDMA; 25%BisEMA +65%TEGDMA +10%ethanol; 25%BisEMA +65%TEGDMA +10%HEMA; 100%TEGDMA; 90%TEGDMA +10%ethanol; 90%TEGDMA +10%HEMA. The samples were photoactivated at two temperatures (25°C and 55°C). Degree of conversion (DC) was performed using an infrared spectrophotometer. Elastic modulus (E), flexural strength (FS) and contact angle (CA) tests were also performed. The DP of an infiltrant in demineralized enamel was determined by confocal laser scanning microscopy (CLSM) using an indirect labeling technique. The data were analyzed by two-way ANOVA and Tukey's test. DC increased after preheating in all the groups; however, 90%TEGDMA+10%ethanol showed the lowest DC for both temperatures, and the lowest E. Preheating did not influence E or FS. The CA increased at 55°C for most groups, but decreased for groups containing HEMA. Temperature did not seem to influence DP, and Icon showed the lowest DP values. The 100%TEGDMA composition showed more homogeneous penetration, whereas Icon showed heterogeneous and superficial penetration. The preheating technique does not improve all properties in all the material compositions. The composition of a material can influence and improve its properties.


Assuntos
Esmalte Dentário , Polietilenoglicóis , Ácidos Polimetacrílicos , Viscosidade , Teste de Materiais , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Módulo de Elasticidade , Metacrilatos
15.
Braz. dent. j ; 30(6): 592-598, Nov.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055449

RESUMO

Abstract This study aimed to evaluate the polymerization properties of bulk-fill materials (low and high-viscosity) by using high-intensity continuous light and intermittent photo-activation in terms of polymerization shrinkage stress and degree of conversion (DC). The following Bulk-fill and Conventional nanofilled resin composites were evaluated: Filtek Z350XT Flow (3M/ESPE), SureFil SDR Flow (Dentsply), Filtek Bulk Fill Flow (3M/ESPE), Filtek Z350XT (3M/ESPE) and Filtek Bulk Fill Posterior (3M/ESPE). A LED device (DB 685, Dabi Atlante) was used for both protocols: continuous uniform and intermittent photo-activation (light-on and light-off cycles) with identical radiant exposure (14 J/cm2). The polymerization shrinkage stress (n=6) was evaluated by inserting a single increment of 12 mm3 between two stainless steel plates (6×2 mm) adapted to a Universal Testing Machine (UTM), at different times. Measurements were recorded after photo-activation. The degree of conversion was evaluated by Fourier transformed infrared spectroscope (FTIR) with an attenuated total reflectance (ATR) accessory (n=5). Data were analyzed by three-way ANOVA and Tukey's HSD (α=0.05) tests. Bulk Fill Posterior presented higher shrinkage stress values when photo-activated with the intermittent technique (p<0.05). The intermittent photo-activation increased the degree of conversion for the low-viscosity bulk-fills (p<0.05). Therefore, the use of modulated photo-activation (intermittent) must be indicated with caution since its use can influence the shrinkage stress and degree of conversion of composites, which varies according to the resin formulations.


Resumo O presente estudo teve como objetivo avaliar as propriedades de polimerização de materiais bulk-fill (baixa e alta viscosidade) utilizando luz contínua de alta intensidade e fotoativação intermitente em relação ao estresse de contração de polimerização e grau de conversão (DC). As seguintes resinas compostas Bulk-fill e nanohíbridas convencionais foram avaliadas: Filtek Z350XT Flow (3M/ESPE), SureFil SDR Flow (Dentsply), Filtek Bulk Fill Flow (3M/ESPE), Filtek Z350XT (3M/ESPE) e Filtek Bulk Fill Posterior (3M/ESPE). Um dispositivo de LED (DB 685, Dabi Atlante) foi utilizado nos dois protocolos: fotoativação contínua e intermitente contínua (ciclos de liga e desliga) com exposição idêntica (14 J/cm2). A tensão de contração de polimerização (n=6) foi avaliada através da inserção de um incremento único de 12 mm3 entre duas placas de aço inoxidável (6×2 mm) adaptadas a uma Máquina de Ensaio Universal (UTM), em tempos diferentes. As medições foram registradas após a fotoativação. O grau de conversão foi avaliado por FTIR-ATR (n=5). Os dados foram analisados ​​pelos testes ANOVA a três fatores e teste de Tukey (α=0,05). A resina Bulk Fill Posterior apresentou maiores valores de tensão de contração quando fotoativadas com a técnica intermitente (p<0,05). A fotoativação intermitente aumentou o grau de conversão nas resinas bulk-fill de baixa viscosidade (p<0,05). Portanto, o uso de fotoativação modulada (intermitente) deve ser indicado com cautela, uma vez que seu uso pode influenciar a tensão de contração e o grau de conversão dos compósitos, o que varia de acordo com as formulações da resina.


Assuntos
Teste de Materiais , Resinas Compostas , Viscosidade , Polimerização
16.
Braz. dent. j ; 30(5): 476-483, Sept.-Oct. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039146

RESUMO

Abstract The aim of this study was to evaluate the bond strength, bottom/top hardness ratio, marginal adaptation, and interfacial nanoleakage of regular viscosity bulk fill composites (RVBFC) and regular viscosity traditional composites (RVTC). Two RVBFC (Filtek Bulk Fill and Aura Bulk Fill) and two RVTC (Filtek Z250XT and Aura) were assessed. Forty conical cavities (4.8×2.8×4.0) were prepared in bovine dentin and restored with composites (n=10). After 24h in water, marginal adaptation was evaluated by staining with a caries detector. The top and bottom surfaces of the conical restorations were stained for five seconds and the gap percentage in the composite/dentin interface was determined using digital images on a measurement program (ImageTool). The Vickers microhardness was measured and the bottom/top microhardness ratio (B/T) was determined. Push-out bond strength test was performed in a universal testing machine (0.5mm/min) and failure modes were evaluated in a stereomicroscope (20×). Other specimens (n=3) were produced for interfacial nanoleakage evaluation. Data were analyzed using one and two-way ANOVA and Tukey's test (α=0.05). The gap percentage was higher in the bottom compared to the top. The B/T ratio of the Aura Bulk Fill was statistically lower than other composites. Push-out bond strength were similar among composites. The RVBFC presented lower nanoleakage than the RVTC in the bottom of the conical restoration and there was no difference among the materials in the top surfaces. In conclusion, Filtek Bulk Fill performed better than Aura Bulk Fill regarding the analyzed properties.


Resumo O objetivo deste estudo foi avaliar a resistência de união, razão base/topo de microdureza, adaptação marginal e nanoinfiltração interfacial de resinas compostas bulk fill (BF) e tradicional (RT) de viscosidade regular.: Duas BF (Filtek Bulk Fill e Aura Bulk Fill) e duas RT (Filtek Z250XT e Aura) foram testados. Quarenta cavidades cônicas (4,8×2,8×4,0) foram preparadas em dentina bovina e restauradas com os compósitos (n=10). Depois de 24 h em água, a adaptação marginal foi avaliada por meio do corante com detector de cárie. As faces de topo e base das restaurações cônicas foram coradas por cinco segundos e a porcentagem de fendas na interface compósito/dentina foi determinada utilizando-se imagens analisadas num programa (ImageTool). A microdureza Vickers foi mensurada e a razção base/topo de microdureza (B/T) foi determinada. A resistência de união por push-out foi executada numa máquina de ensaios universal (0,5mm/min) e o padrão de fratura avaliado num estereomicroscópio (20x). Espécimes adicionais (n=3) foram confeccionados para avaliação da nanoinfiltração interfacial. Os dados foram analisados por meio de ANOVA a dois fatores e teste de Tukey (a=0,05). A porcentagem de fendas foi maior na base que no topo. A B/T da Aura Bulk Fill foi estatisticamente menor que os demais compósitos. A resistência de união por push-out foi similar entre os compósitos. As BF apresentaram menos nanoinfiltração que as RT na base das restaurações cônicas e não houve diferenças entre os materiais no topo. Conclui-se que a Filtek Bulk Fill comportou-se melhor que a Aura Bulk Fill considerando-se as propriedades analisadas.


Assuntos
Animais , Resinas Compostas , Cárie Dentária , Viscosidade , Teste de Materiais , Bovinos , Dentina , Dureza
17.
Hig. Aliment. (Online) ; 33(288/289): 3122-3126, abr.-maio 2019. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482526

RESUMO

A utilização de subprodutos em um novo processo resulta em maior lucro para o produtor. Entretanto, deve-se verificar a qualidade do produto final, pois a maior concentração do soro do leite pode provocar redução em parâmetros como viscosidade e sinérese. O objetivo do presente estudo é de analisar o comportamento reológico de achocolatado industrializado de duas diferentes marcas. Para leitura da viscosidade foi utilizado um viscosímetro de Brookfield, modelo DVII+Pro utilizando o splidlen nº 2 com as seguintes rotações: 50, 60, 70, 80, 100, 120, 140 rpm. A partir de uma análise estatística dos dados obtidos, utilizando o software STATISTICA 7.0 obtivemos os dados referentes à tensão de cisalhamento (Pa) e taxa de deformação (s-1). Valores inferiores de viscosidade aparente e taxa de deformação foram observadas na amostra 1, Ambas as amostras, demonstraram o comportamento de um fluido não newtoniano com características semelhantes ao plástico de Bingham.


Assuntos
Chocolate/análise , Reologia/métodos , Soro do Leite/química , Viscosidade , Indústria de Laticínios
18.
Hig. Aliment. (Online) ; 33(288/289): 1503-1507, abr.-maio 2019. ilus, tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482191

RESUMO

O amido é a principal fonte energética da alimentação humana e possui diversas funcionalidades tecnológicas. O objetivo deste trabalho foi avaliar as propriedades de pasta e a morfologia dos grânulos de amido de araruta. As propriedades viscoamilográficas do amido de araruta do Vale do Jiquiriçá e industrializado foram, respectivamente: viscosidade máxima de 7532 cP e 6865 cP, quebra da viscosidade de 4449 cP e 5378 cP, viscosidade final de 4897 cP e 2946 cP, retrogradação de 1814 cP e 1459 cP, tempo de pico 6,53 min e 5,73 min e temperatura de pasta igual a 71,05°C e 63,10°C. Os grânulos têm estrutura oval de tamanhos variados e danos na sua estrutura, possivelmente causados na extração. Essa caracterização serve como base para a determinação das condições ideais de processamento e usos em potencial para a indústria de alimentos.


Assuntos
Amido/fisiologia , Amido/ultraestrutura , Amidos e Féculas , Marantaceae , Microscopia Eletrônica de Varredura , Viscosidade
19.
Braz. oral res. (Online) ; 33: e125, 2019. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1100928

RESUMO

Abstract Atraumatic Restorative Treatment (ART) is one of the strategies used to control dental caries; it involves hand instruments for removal of carious tissue, and restorations using high-viscosity Glass Ionomer Cement (GIC). The present controlled clinical trial aimed to evaluate the performance of low-cost GIC indicated for ART in primary teeth, compared with high-viscosity GIC, after one year of follow-up. Two-to six-year-old children with dentin caries lesions on one or two surfaces of anterior and posterior teeth were selected. The children were randomly assigned to 2 groups according to the restorative material used: G1 (control) - Ketac Molar®; G2 (experimental) - Vitro Molar®. Treatments were performed in a school setting, following the guidelines of the ART. A total of 728 restorations were performed in 243 children. Descriptive analysis and Poisson regression were applied, with a significance level of p < 0.05. After 12 months, 559 (76.8%) restorations were re-evaluated. The success rate was evaluated by the prevalence ratio (PR), associated with restorations performed in primary second molars (PR = 1.21; 95%CI = 1.03-1.42), and with small (PR = 1.35; 95%CI = 1.14-1.60) or medium cavities (PR = 1.29; 95%CI = 1.08-1.55), using Ketac Molar® material (PR= 1.07; 95%CI = 1.01-1.15), considering p < 0.05. Small or medium restorations in primary second molars performed with high-viscosity GIC (Ketac Molar®) were more successful than restorations performed with low-cost GIC indicated for ART.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Cárie Dentária/terapia , Tratamento Dentário Restaurador sem Trauma/métodos , Cimentos de Ionômeros de Vidro/química , Fatores de Tempo , Dente Decíduo , Viscosidade , Teste de Materiais , Distribuição de Poisson , Índice CPO , Resultado do Tratamento , Falha de Restauração Dentária , Restauração Dentária Permanente/métodos , Cimentos de Ionômeros de Vidro/uso terapêutico
20.
ARS med. (Santiago, En línea) ; 44(1): 46-50, 2019. ilus
Artigo em Espanhol | LILACS | ID: biblio-1046760

RESUMO

Introducción: la Macroglobulinemia de Waldenström (MW) es un tipo raro de linfoma de células B caracterizado por la proliferación de células linfoplasmocíticas que secretan altas cantidades de inmunoglobulinas M (IgM) monoclonales. Puede presentarse con una amplia gama de síntomas, entre ellos los derivados del aumento de la viscosidad plasmática. Métodos: reportamos un caso de MW que presentó una trombosis de la vena central de la retina (TVCR) bilateral en el contexto de un síndrome de hiperviscosidad (SHV). El objetivo de este trabajo fue revisar algunos aspectos clínicos de la MW, con especial énfasis en el SHV y la TVCR. Resultados: las manifestaciones clínicas y de laboratorio de la MW son inespecíficas y comunes a otras neoplasias hematológicas. El SHV se produce cuando los niveles de IgM sobrepasan los 3 mg/dL, situación que ocurre en un 15-30 por ciento de los pacientes. La TVCR es una complicación grave y rara asociada al SHV, presentándose típicamente como una pérdida de agudeza visual indolora. El fondo de ojo exhibe signos característicos, como tortuosidad venosa y hemorragias retinales hasta la periferia, y la angiografía con fluorosceína y la OCT pueden orientar al diagnóstico y guiar el manejo. El tratamiento incluye la plasmaféresis y tratamientos oftalmológicos basados en agentes antioangiogénicos. Conclusión: la MW es una enfermedad incurable. Sin embargo, es importante sospechar una TVCR en pacientes que debutan con una pérdida de agudeza visual, ya que existen tratamientos efectivos en el manejo de esta complicación. (AU)


Introduction: Waldenstrom's Macroglobulinemia (WM) is a rare type of B-cell lymphoma characterized by proliferation of lymphoplasmocitarian cells that secrete high amounts of monoclonal immunoglobulin M (IgM). It may present with a wide range of symptoms, including the ones that derivatives of the increase in plasma viscosity. Methods: we report a case of WM that presented a bilateral central retinal vein occlusion (CRVO) in the context of a hyperviscosity syndrome (HVS). The objective of this study was to review clinical aspects of the WM, with special emphasis on the HVS and the CRVO. Results: the WM laboratory and clinical manifestations are common to other hematological malignancies. The HVS occurs when levels of IgM exceed 3 mg/dL, situation that occurs in 15-30 percent of patients. The CRVO is a serious and rare complication associated with the HVS, typically presented as a painless visual acuity loss. The fundoscopic examination exhibits characteristic signs, such as venous tortuousity and retinal hemorrhages in all four quadrants and most numerous in the periphery; angiography with fluoroscein and the OCT can orientate the diagnosis and guide the management. The treatment includes plasmapheresis and other ophthlamological treatments based on antiangiogenic agents. Conclusion: the WM is an incurable disease. However, it is important to suspect a CRVO in patients who made their debut with a loss of visual acuity, since there are effective treatments in the management of this complication.(AU)


Assuntos
Humanos , Oclusão da Veia Retiniana , Macroglobulinemia de Waldenstrom , Terapêutica , Viscosidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA