Fluoride and silver ion concentrations and pH in silver diamine fluoride solutions from Argentina / Concentraciones de fluoruro y plata y pH en soluciones de diamino fluoruro de plata producidos en Argentina

ABSTRACT The aim of this study was to measure the fluoride (F) and silver (Ag) ion concentration and the pH, over time, of 2 solutions of 38% silver diamine fluoride (SDF) produced in Argentina. The brand Fluorsilver® was established as Group 1 (G1) (Densell), and the brand FAgamin® (Tedequim) as Group 2 (G2), each with two different lots. The following were determined at time 0 (t0) and 30 days after opening (t30): a) fluoride concentration (w/v) by visible spectrophotometry b) Ag content (w/v) by atomic absorption spectrophotometry c) pH. Results: The data in the freshly opened bottles were for G1 lot1/lot2: a) 0.96/1, b) 8.3/7.8, c).11.5/11.3; G2 lot1/lot2: a) 11.5/9.9, b) 39/39, c) 7/6,9; and after 30 days, G1 lot1/lot2: a) 0.85/0.81, b) 7.2/8.2, c) 11.3/11.6; G2 lot1/lot2: a) 9.35/8.43, b) 38/38, c) 7.6/7.6. Conclusion In relation to the expected values (5.0-5.9% fluoride and 24.4-28.8% silver), the average concentration of fluoride and silver ions was lower for G1, but higher for G2. The pH was alkaline for G1 and neutral for G2. Over the 30 days, the content of fluoride and silver tended to decrease.

RESUMEN El objetivo de este estudio fue medir las concentraciones de iones de fluoruro (F) y plata (Ag) y el pH, de 2 soluciones de diamino fluoruro de plata (SDF) al 38% producidas en Argentina. Se estableció como Grupo 1 (G1) la marca Fluorsilver® (Densell), y FAgamin® (Tedequim) como Grupo 2 (G2), cada uno con dos lotes diferentes. Se determinó: a) la concentración de fluoruro (p/v) por espectrofotometría visible, b) el contenido de Ag (p/v) por espectrofotometría de absorción atómica y c) el pH, y fue medido en un tiempo 0 (t0) y 30 días después de la apertura del frasco (t30). Resultado: En tiempo 0 para G1 lote1/lote2 fue: a) 0,96/1, b) 8,3/7,8 c).11,5/11,3 y G2 lote1/lote2: a) 11,5/9,9, b) 39/39, c) 7/6,9. A los 30 días G1 lote1/lote2: a) 0,85/0,81, b) 7,2/8,2, c) 11,3/11,6 y G2 lote1/lote2: a) 9,35/8,43, b) 38/38, c) 7,6/7,6. La concentración de iones de fluoruro y plata para G1 fue menor en relación a los valores esperados (5,0-5,9% de fluoruro y 24,4- 28.8% plata), sin embargo G2 obtuvo valores más altos. G1 muestra resultados de pH alcalino y G2 neutro. A lo largo de los 30 días, el contenido de fluoruro y plata tiende a disminuir.

Research progress on factors affecting bacterial adhesion on the oral implant surface / 口腔疾病防治

@#Reducing the adhesion of microorganisms and the formation of biofilms on implant surfaces can prevent peri-implant inflammation and optimize the long-term prognosis of implanted dentures. To provide theoretical support for the development of new materials or the modification of existing materials and the improvement of the success rate of implant repair, a literature review was conducted, which shows that the factors influencing bacterial adhesion on dental implant surfaces included the type of implant material, material roughness, nonspecific physical and chemical properties, the type of antibacterial coating, the components of the acquired membrane on the implant surface, the structure of the bacterial cell wall, etc. The current research direction of implant materials aims to reduce bacterial adhesion and promote bone bonding. However, there is no consensus on the physical and chemical properties of implants that meet this requirement. At present, the development trend in implant materials is guided by research of the “core microbiome” of peri-implant inflammation, based on study of the factors related to the adhesion of pathogenic microorganisms to the implant surface, which is organically combined with a variety of modification methods to change the surface-related properties of the implant materials and even to endow the implant with antibacterial properties to reduce or inhibit the adhesion of pathogenic bacteria to the implant.

Microbiological and physical-chemical characteristics of honeys from the bee Melipona fasciculata produced in two regions of Brazil / Características microbiológicas e físico-químicas de méis de abelha Melipona fasciculata produzidos em duas regiões do Brasil

ABSTRACT: The honey from Tiúba bees (Melipona fasciculata) is commercially important in the Brazilian state of Maranhão. However, the absence of any specific legislation for this kind of honey is an obstacle to its increased production and commercialization. Determining the microbiological and physical-chemical characteristics of different Tiúba honey can inform the elaboration of specific legislation. Thus, honey samples from two Water Catchment Areas in Maranhão (Munim and Pericumã, sample size 20 for each) were collected and submitted for microbiological analysis (total coliforms, thermotolerant coliforms, molds and yeasts, Clostridium sulfite reducers and Salmonella sp.) and physical-chemical analysis (moisture content, reducing and non-reducing sugars, insoluble and soluble solids, ash content, acidity and pH). Most of honeys sampled were suitable for human consumption, except for one sample from Pericumã. Honeys from the two water catchment areas presented differences in some physicochemical characteristics, which can be attributed to the botanic, soil and climatic diversity of the two areas. Still, these Tiúba honey samples did not fall within the Brazilian legislation for Apis mellifera honey for some of the physical-chemical characteristics, and so is not properly regulated, thus reinforcing the need for specific legislation for this type of honey.

RESUMO: O mel de Tiúba (Melipona fasciculata) tem importância comercial na região do estado do Maranhão, no entanto a ausência de uma legislação específica para este mel entrava a ampliação de sua produção e comercialização. Dessa forma, faz-se necessário determinar as características microbiológicas e físico-químicas de méis de Tiúba, com o objetivo de fornecer subsídios para a elaboração de uma legislação específica. Assim, amostras de méis provenientes de duas bacias hidrográficas do Maranhão (Munim n = 20, e Pericumã n = 20) foram coletadas e submetidas às análises microbiológicas (coliformes totais, coliformes termotolerantes, bolores e leveduras, Clostridium sulfito redutores e Salmonella sp.) e físico-químicas (umidade, açúcares redutores e não redutores, sólidos insolúveis e solúveis, cinzas, acidez e pH). A maioria dos méis apresentou-se adequado microbiologicamente ao consumo humano, exceto uma amostra de mel proveniente de Pericumã. Os méis provenientes das duas bacias hidrográficas apresentaram diferenças em algumas características físico-químicas, o que pode ser atribuído à diversidade botânica, edáfica (solo) e climática das duas bacias. Ainda, os méis de Tiúba não se adequaram à legislação brasileira de Apis mellifera para algumas características físico-químicas, o que não permite sua regulamentação e, assim, reforça a necessidade de legislação específica para este tipo de mel.

Effect of pre-emulsified sesame oil on physical-chemical and rheological properties of pork batters

Abstract Physical-chemical and rheological properties of pork batters as affected by replacing pork back-fat with pre-emulsified sesame oil were investigated. Replacement of pork back-fat with pre-emulsified sesame oil, improved L* value, moisture and protein content, hardness, cohesiveness, and chewiness, declined a* value, fat content and energy, but not affect cooking yield. When used pre-emulsified sesame oil to replace pork back-fat 50%, the sample had the highest L* value and texture. According to the results of dynamic rheological, replaced pork back-fat by pre-emulsified sesame oil increased the storage modulus (G') values at 80 °C, and formed firm gel. The result of Low-field nuclear magnetic resonance (LF-NMR) shown that the batters with pre-emulsified sesame oil had higher water holding capacity than the control. Overall, the batters with pre-emulsified sesame oil enabled lowering of fat and energy contents, making the pork batter had better texture.

Characterization of Bis-Acryl Composite Resins for Provisional Restorations

Abstract This study investigated the in vitro performance of the commercial bis-acryl composite resins Systemp C&B II (SYS, Ivoclar Vivadent), Protemp 4 (PT4, 3M ESPE), Structur 2C (ST2, Voco) and ProviPlast (PVP, Biodinamica). Characterization involved optical (color stability, translucency parameter, fluorescence), surface (roughness, morphology and elemental composition), physical-chemical (viscosity, polymerization kinetics) and mechanical analyses (Poisson ratio, biaxial flexural strength, flexural modulus). Most tests were carried out after 24 h, but optical and mechanical analyses were carried out after storage in water at 37 °C for 1, 15, and 30 days. Data were statistically analyzed (a=0.05). Most results were material dependent. SYS and PT4 showed stability in color and translucency over time. All materials had similar or higher fluorescence than human enamel. SC2 and PVP showed rougher surfaces than the other bis-acryl composites. Smaller filler particles were observed on the surface of PT4 and PVP compared with the coarser particles from ST2 and SYS. Viscosity readings indicated a thixotropic behavior for all tested materials. SYS had the lowest and PT4 the highest degree of C=C conversion after 10 min. In the polymerization kinetics, PT4 had the highest maximum polymerization rate and reached earlier the transition between polymerization autoacceleration and autodeceleration. PT4 and SYS had significantly higher flexural strength and modulus than ST2 and PVP for most storage times. Results for Poisson ratio varied between materials. Longer storage periods were generally associated with higher frequency of catastrophic failures in the flexural tests. In conclusion, the performance of bis-acryl composite resins varied largely among materials.

Resumo Este estudo investigou o desempenho in vitro de quatro resinas compostas bisacrílicas comerciais: Systemp C&B II (SYS, Ivoclar Vivadent), Protemp 4 (PT4, 3M ESPE), Structur 2C (ST2, Voco) e ProviPlast (PVP, Biodinamica). A caracterização envolveu análises ópticas (estabilidade de cor, parâmetro de translucidez, fluorescência), de superfície (rugosidade, morfologia e composição elementar), físico-químicas (viscosidade, cinética de polimerização) e mecânicas (razão de Poisson, resistência à flexão biaxial, módulo de elasticidade). A maioria dos testes foram realizados após 24 h, enquanto análises ópticas e mecânicas foram realizadas após armazenamento em água a 37 °C por 1, 15 e 30 dias. Os dados foram analisados estatisticamente (a=0,05). Grande parte dos resultados foi dependente do material. SYS e PT4 mostraram estabilidade de cor e translucidez ao longo do tempo. Todos os materiais apresentaram fluorescência similar ou maior que o esmalte humano. SC2 e PVP apresentaram superfícies mais rugosas que os outros materiais. Menores partículas de carga foram observadas na superfície de PT4 e PVP comparadas às partículas mais irregulares de ST2 e SYS. As leituras de viscosidade indicaram comportamento tixotrópico para todos os materiais testados. SYS teve a menor e PT4 o maior grau de conversão de C=C após 10 min. Na cinética de polimerização, PT4 teve a maior taxa máxima de polimerização e atingiu mais cedo a transição entre autoaceleração e autodesaceleração da polimerização. PT4 e SYS apresentaram resistência à flexão e módulo de elasticidade significativamente maiores que ST2 e PVP na maioria dos períodos de armazenamento. Resultados da razão de Poisson variaram entre os materiais. Períodos mais longos de armazenamento foram em geral associados a maior frequência de falhas catastróficas nos testes de flexão. Em conclusão, o desempenho das resinas compostas bisacrílicas variou amplamente entre os materiais.

Caracterização físico-química de doze biomateriais utilizados como enxertos ósseos na Implantodontia / Physical and chemical characterizations of twelve biomaterials used as bone grafts in Implantology

A necessidade de reconstruções ósseas nas áreas médico-odontológicas proporcionou um avanço no estudo dos biomateriais. As características físico-químicas dos biomateriais desenvolvidos influenciam nos fenômenos biológicos que ocorrem no processo regenerativo. Sendo assim, o objetivo deste trabalho foi apresentar os resultados da caracterização físico-química de 12 biomateriais utilizados como enxertos ósseos na Implantodontia. A caracterização físico-química englobou análise granulométrica, microscopia eletrônica de varredura (MEV), difração de raios X (DRX), determinação da área superficial específica e cristalinidade das amostras. O resultado demonstrou que todas as amostras inorgânicas eram constituídas de hidroxiapatita, com diferentes faixas granulométricas, área de superfície variando de 0,18 a 81,4 m2/g e cristalinidade variando de baixa a alta, demonstrando que apesar da semelhança de suas composições, os biomateriais analisados apresentaram diferenças de parâmetros físico-químicos.

The need for bone reconstruction in the medical and dental field provided a breakthrough in the study of biomaterials. The physicochemical characteristics of biomaterials are developed directly targeting the biological phenomena occurring in the regenerative process. Therefore, the objective of this study was to present the results of physical-chemical characterization of twelve biomaterials used in Implantology. Physicochemical characterization was carried out by using electron microscopy (SEM), X-ray diffraction (XRD), surface area (BET) measurement and crystallinity of samples. The result reported that all inorganic samples were constituted of hydroxyapatite, with different grain size bands, area of surface varying from 0.18 to 81.4 g/m2 with a low to high crystallinity, demonstrating that although presenting similar compositions, the analyzed biomaterials presents differences on their physicochemical parameters.

Evaluación de propiedades físico-químicas de tinturas de Quassia amara y Maytenus ilicifolia / Assessment of physicochemical properties of Quassia amara and Maytenus ilicifolia tinctures

Las plantas Quassia amara y Maytenus ilicifolia son conocidas por sus propiedades terapéuticas sobre el aparato digestivo. En el presente trabajo ambas plantas se investigaron unidas, mediante la mezcla de las tinturas obtenidas, con el objetivo de potenciar su acción como fitofármaco. Este estudio resumió las propiedades físico-químicas de las tinturas obtenidas por percolación, con el empleo de una solución hidroalcóholica al 60 % y un tiempo de extracción de 48 h en 2 variantes: 1) mezclas de las tinturas obtenidas de cada planta, al 20 % en una proporción de 10-90 % (QA-MI), la cual se denominó tintura C. 2) Mezcla del material vegetal de ambas plantas en las mismas proporciones anteriores, en el equipo, para obtener la tintura D. Los parámetros evaluados en ambas tinturas (pH, densidad relativa, índice de refracción, sólidos totales), se compararon estadísticamente. Se comprobó que solo los sólidos totales ofrecen diferencias significativas, con valores superiores en la tintura D, la cual fue seleccionada para el estudio de estabilidad. El extracto D se estudió durante 3 meses a 3 temperaturas diferentes: refrigeración, ambiente y 40 °C. Se comprobó que en refrigeración no ocurren cambios en los parámetros evaluados y en las otras temperaturas aparecen ligeros cambios en pH y contenido alcohólico.

The Quassia amara and Maytenus ilicifolia plants are known by its therapeutical properties on digestive tract. In present paper both plants were researched together by means of mixing of tinctures obtained to potentiate its phytopharmacologic action. Present study summarizes the physical-chemical properties of tinctures obtained by percolation using a 60 %-hydroalcoholic solution and a extraction time of 48 hrs in two variants: 1) mixtures of tinctures obtained from each plant to 20 % at a 10-90 % ratio (QA-MI), which was called C-tincture, the mixture of vegetal material in both plants in the same prior ratios in equipment, to obtain D-tincture. Parameters assessed in both tinctures (pH, relative density, refraction rate, total solids) were statistically compared. It was proved that total solids have significant differences with higher values present in D-tincture, which was selected for stability study. D-extract was studied during three months at different temperatures: refrigeration, room-temperature and at 40 ºC. In refrigeration temperature there are not changes in parameters assessed and in the other temperatures there appear slight changes in pH and alcoholic content.

Dipteryx lacunifera seed oil: characterization and thermal stability / Óleo de sementes de fava de morcego: caracterização e estabilidade térmica

The Dipteryx lacunifera Ducke is an oleaginous legume with high oil and protein content that can be used in human nutrition. The specie is a native of the Piauí and Maranhão state in the north east of Brazil. The measure physico-chemical properties of the oil are specific density, refractive index, acid, peroxide, iodine and saponification values of 0.91, 1.4651, 0.60 ( percent oleic acid), 2.81, 70.80 and about 179, respectively. Gas chromatographic analysis of the oil showed the presence of 20.6 percent saturated, 65.1 percent monounsaturated and 14.3 percent polyunsaturated fatty acids. The saturated fatty acids C6:0, C8:0, C12:0 and C17:0 were present in trace (<0.01 percent) amounts while the C16:0, C18:0, C20:0, C22:0 and C24:0 were at concentrations of 10.3, 5.4, 3.4, 0.9 and 0.6 percent of the total fatty acids. Unsaturated fatty acids C18:1, C18:2, C18:3 and C22:2 contents were 65.1, 14.1, 0.3 percent and trace (0.01 percent), respectively. Thermal analysis (TG/DTG) revealed that the thermal decomposition of the oil occurs in two steps corresponding to the unsaturated and saturated fatty acids. The oil, when heated to a temperature of 180º C for 400 min showed smaller loss in mass than commercial soy, sunflower and corn oils. The curve DSC indicated an endothermic event with enthalpy variation (DH) of -56.7 Cal.g-1 in the temperature interval of 340 ºC (Ti) the 463º C (Tf), with maximum in 411.1º C (Tm).

A Dipteryx lacunifera Ducke (fava de morcego) é uma leguminosa oleaginosa com elevado conteúdo em proteínas e óleo podendo ser usada na nutrição humana. A espécie é nativa dos estados do Piauí e Maranhão do nordeste do Brasil. Mensurações das propriedades físico-químicas do óleo densidade especifica, índice de refração, acidez, peróxidos, iodo e saponificação foram 0.91, 1.4651, 0.60 ( por cento ácido oléico), 2.81, 70.80 e 179, respectivamente. A análise do óleo por cromatografia gasosa mostrou a presença de 20.6 por cento de ácidos graxos saturados, 65.1 por cento de monoinsaturados e 14.3 por cento poliinsaturados. Os ácidos graxos C6:0, C8:0, C12:0 e C17:0 estão presentes em quantidades de traços (<0.01 por cento) enquanto os C16:0, C18:0, C20:0, C22:0 e C24:0 estão em concentrações de 10.3, 5.4, 3.4, 0.9 e 0.6 por cento, respectivamente, dos ácidos graxos totais. O conteúdo dos ácidos graxos insaturados C18:1, C18:2, C18:3 e C22:2 foram 65.1, 14.1, 0.3 por cento e traço (0.01 por cento), respectivamente. A análise térmica (TG/DTG) revelou que a decomposição térmica do óleo ocorre em dois estágios correspondentes aos ácidos graxos insaturados e saturados. O óleo quando aquecido na temperatura de 180º C por 400 min mostrou menor perda massa que o óleo comercial de soja, girassol e milho. A curva DSC indicou um evento endotérmico com variação de entalpia (DH) de -56.7 Cal.g-¹ no intervalo de temperatura 340º C (Ti) a 463º C (Tf), com máximo em 411.1º C (Tm).