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Braz. J. Pharm. Sci. (Online) ; 56: e18601, 2020. tab, graf
Article in English | LILACS | ID: biblio-1249143


The objective of this work was to develop and characterize liposomes loaded with silver nanoparticles (LAgNPs) to show improvement in stability characteristics. AgNPs were prepared by the green synthesis method with Aloe vera gel extract and exposure to sunlight. Liposomes were prepared by the modified reverse phase method. Particle size, polydispersity index, zeta potential, as well as the scanning electron microscopy (SEM) morphological aspects of AgNPs and LAgNPs were evaluated. In addition, was used flame atomic absorption spectroscopy to determine the amount of AgNP that was encapsulated in liposomes. The AgNPs presented as amorphous and polydisperse structures, with a mean diameter of 278.46 nm and zeta potential of -18.3 mV. LAgNPs had a mean diameter between 321 and 373 nm, the polydispersity index close to 0.2 and a zeta potential around -40 mV, which indicates greater stability to the AgNPs. The images obtained by SEM show semicircular structures for AgNPs and well-defined spherical shape for LAgNPs. The percentage of encapsulation was between 51.81 to 58.83%. These results showed that LAgNPs were obtained with adequate physicochemical characteristics as a release system.

Silver , Nanoparticles/analysis , Liposomes/analysis , Sunlight/adverse effects , Microscopy, Electron, Scanning/methods , Atomic Absorption Spectroscopy/methods , Aloe/classification , Methods
Braz. J. Pharm. Sci. (Online) ; 56: e18171, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132034


Gold coated magnetite nanoparticles were prepared and coated with ranibizumab as an ocular drug delivery system. The surface morphologies of the nanoparticles were determined by Scanning Electron Microscopy (SEM). The size and surface charge were determined by using the dynamic light scattering (DLS) technique. Crystallographic properties of the gold coated Fe3O4 nanoparticles were recorded on X-ray diffractometer (XRD) the XRD pattern of nanoparticlees were shown to have uniqe Fe3O4 and gold peaks. Conjugation of ranibizumab onto nanoparticles was achieved using the physical adsorption method. The amount of ranibizumab on the surface of the nanoparticles was determined by thermogravimetric analysis (TGA). In the in vitro release studies performed using UV spectroscopy; it was found that almost 60% of antibodies were released within the first 30 minutes. Antibody activity after release studies was also proved with ELISA. Non-toxicity of gold coated Fe3O4 particles were proved with MTT. Results of the studies, showed that the antibody conjugated magnetic nanoparticle system could be a potential treatment system for ocular diseases.

In Vitro Techniques/instrumentation , Magnetite Nanoparticles/administration & dosage , Ranibizumab/adverse effects , Spectrum Analysis/instrumentation , X-Rays , Enzyme-Linked Immunosorbent Assay/instrumentation , Microscopy, Electron, Scanning/methods , Drug Delivery Systems , Dynamic Light Scattering/instrumentation , Gold , Methods
Braz. J. Pharm. Sci. (Online) ; 56: e18474, 2020. tab, graf
Article in English | LILACS | ID: biblio-1249171


Due to the increase of bacterial resistance, the search for new antibiotics is necessary and the medicinal plants represent its most important source. The aim of this study was to evaluate the antibacterial property of extract and fractions from Protium spruceanum leaves, against pathogenic bacteria. By means of diffusion and microdilution assays, the crude extract was active against the nine bacteria tested being the hydromethanolic fraction the most active. During phytochemical procedures, procyanidin (1) and catechin (2) were identified as the main antibacterial constituents of this fraction. In silico results obtained using PASSonline tool indicated 1 and 2 as having good potential to interact with different targets of currently used antibiotics. These results no indicated potential to none DNA effect and indicated the cell wall as mainly target. Electrophoresis result supported that had no DNA damage. Cell wall damage was confirmed by propidium iodide test that showed increased membrane permeability and by cell surface deformations observed in scanning electronic microscopy. The in vitro assays together with the in silico prediction results establish the potential of P. spruceanum as source of antibacterial compounds that acts on important bacterial targets. These results contribute to the development of natural substances against pathogenic bacteria and to discovery of new antibiotics.

Plants, Medicinal/adverse effects , In Vitro Techniques/methods , Plant Extracts/analysis , Catechin , Anti-Bacterial Agents/analysis , Computer Simulation , Microscopy, Electron, Scanning/methods , Plant Leaves/classification , Burseraceae/classification , Phytochemicals
Braz. J. Pharm. Sci. (Online) ; 56: e18784, 2020. tab, graf
Article in English | LILACS | ID: biblio-1249176


Antibacterial activity and good mechanical properties are some of the characteristics required for an appropriate film dressing. A novel polymer blend was developed for wound healing application. Twenty-four formulations using the polymers chitosan, poly(vinyl alcohol) and/or ɛ-Polylysine and the plasticizer glycerol were designed using factorial design and then the films were prepared by the casting/solvent evaporation method. Seventeen films were obtained among the twenty-four proposed formulations that were characterized by Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Mechanical properties, such as tensile strength (σ), elongation at break (ɛ) and Young's modulus (Y) as well as antibacterial properties were determined. The best candidate was then further analyzed with regard to porosity, Water Vapor Transmission Rate (WVTR), swelling and cytotoxicity experiments. The results showed a film with semi-occlusive characteristics, good mechanical properties and no toxic. Incorporation of ɛ-Polylysine increased antibacterial activity against gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria

Bandages , Chitosan/pharmacology , Polylysine/pharmacology , Wound Healing/drug effects , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared , Glycerol/pharmacology
Int. j. morphol ; 37(2): 477-480, June 2019. graf
Article in English | LILACS | ID: biblio-1002246


The renal glomerulus is coated by fenestrated endothelial cells and externally covered by specialized epithelial cells, known as podocytes. Scanning electron microscopy becomes an important and effective tool for its studies. Normally, samples destined for scanning microscopy are covered with a thin metallic layer. However, this step can be dispensed for some analyzes. We aimed to compare coated and uncoated samples for evaluation of the glomerular morphology of the Wistar rat kidney. Cortical region of the kidney of the 5month-old male Wistar rats were used. The fragments followed the routine procedure for scanning electron microscopy processing. Half of 10 fragments were coated with palladium gold and the remaining were not coated. Auriga Compact FIB - SEM scanning electron microscope was used to observe the samples. Different increases and voltages was evaluated. For the uncoated samples, when using voltages of 2 KV (or higher) a great charging was observed, impairing the use of such voltage. Thus, these samples were always observed under voltage of 0.5 KV. On the other hand, in the coated samples, the use of 2 KV was adequate. Almost as a consequence, in the coated samples, the podocyte structures were better characterized, generating better images. Inversely, in the uncoated samples, it was possible to visualize the desired structures and to detect the morphological characteristics of these. The results showed that it is possible to use kidney samples without previous coating to evaluate the glomerular morphology at the ultrastructural level, serving as a tool in the study of pathologies.

El glomérulo renal está recubierto por células endoteliales fenestradas y cubierto externamente por células epiteliales especializadas, conocidas como podocitos. La microscopía electrónica de barrido se convierte en una herramienta importante y efectiva para sus estudios. Normalmente, las muestras destinadas a microscopía de barrido se cubren con una capa metálica delgada. Sin embargo, este paso se puede dispensar para algunos análisis. El objetivo fue comparar muestras recubiertas y no recubiertas para evaluar la morfología glomerular del riñón de rata Wistar. Se utilizó la región cortical del riñón de ratas Wistar macho de 5 meses de edad. Se realizó el procedimiento de rutina para el procesamiento de microscopía electrónica de barrido. La mitad de 10 fragmentos se recubrieron con oro paladio y los restantes no se recubrieron. Se utilizó un microscopio electrónico de barrido SEM Auriga Compact FIB para observar las muestras. Se evaluaron diferentes aumentos y voltajes. Para las muestras no recubiertas, al usar voltajes de 2 KV (o más) se observó una gran carga, impidiendo el uso de dicho voltaje. Por lo tanto, estas muestras siempre se observaron a bajo voltaje de 0,5 KV. Por otro lado, en las muestras recubiertas, el uso de 2 KV fue adecuado. Como consecuencia, en las muestras recubiertas, las estructuras de los podocitos se caracterizaron mejor, generando mejores imágenes. Inversamente, en las muestras no recubiertas, fue posible visualizar las estructuras deseadas y detectar las características morfológicas de éstas. Los resultados mostraron que es posible utilizar muestras de riñón sin recubrimiento previo para evaluar la morfología glomerular a nivel ultraestructural, que sirve como una herramienta en el estudio de patologías.

Animals , Male , Rats , Microscopy, Electron, Scanning/methods , Glomerular Filtration Barrier/ultrastructure , Rats, Wistar , Kidney Glomerulus/ultrastructure
Pesqui. bras. odontopediatria clín. integr ; 19(1): 4391, 01 Fevereiro 2019. ilus, tab
Article in English | LILACS, BBO | ID: biblio-997975


Objective: To analyze the Biodentine™ capability in guided tissue remineralization. Material and Methods: Four premolar with two cavities per tooth of 3 mm depth were demineralized with EDTA 17% in shaking incubator at 37°C temperature. After 7 days, the sample were washed with aquabidest then were soaked in 20 ml NaCl 1 M (pH 7.0) at 25°C temperature for 8 hours. The samples were divided into two groups: G1: The control group (cavity directly restored with composite resin); G2: Biodentine™ group (cavity with Biodentine™ as a base then restored with composite resin). All samples were stored in shaking incubator under PBS solution at 37°C temperature. SEM, EDX and TEM analysis were performed on the 7th and 14th day. Results: The 14th day Biodentine group had the best SEM remineralization feature with irregular dentine tubular features covered by density of mass. In the EDX analysis, the concentration of calcium ion of the Biodentine group was higher than the control group on the 7th day analysis (Biodentin™ 10.2167 and control 1.9667) and on the 14th day analysis (Biodentine™ 29.833 and Control 22.080). The Biodentine™ group and control group of the 7th and 14th day experienced significant increases in calcium ion concentration while the concentration of phosphate ion in the Biodentine™ and control group had a much lower value of calcium either on the 7th or 14th day. The TEM analysis of Biodentine™ group showed more intrafibrillar remineralization than the control group. The feature of intrafibrillar dentin remineralization is analyzed by looking at the density of black dots in collagen. Conclusion: Biodentine™ is able to trigger the process of remineralization by guided tissue remineralization.

Tooth Remineralization , Bicuspid , Calcium Phosphates , Dentin , Microscopy, Electron, Scanning/methods , Composite Resins , Indonesia
Pesqui. bras. odontopediatria clín. integr ; 18(1): 4101, 15/01/2018. tab, ilus, graf
Article in English | LILACS, BBO | ID: biblio-966927


Objective: To examine the effect of aloe vera that containing bioactive materials on the levels of calcium (Ca) and phosphorus (P) minerals and their ratios around the immediate implanted in alveolar bone. Material and Methods: Research method by conducting experimental test on experimental animals: 9 male mongrel dogs are divided into 3 groups each 3 tails. In each animal was pulled the second premolar teeth on right side and left side, and immediately inserted titanium implant (3mm x 10mm diameter) after the socket filled with 10% aloevera extract on the right side and control on the left side. Analysis of calcium and phosphorus minerals content formed by examination of Energy Dispersive Spectroscopy (EDS) on Scanning Electron Microscope on implant and around bone tissue was done on days 14, 28 and 56. The result of statistical analysis using repeated ANOVA with independent t test. The level of significance was set at 5%. Results: There was a significant difference on calcium level between control and treatment groups on days 14, 28 and 56 (p<0.05). There was no significant difference on phosphorus level between control and treatment groups (p>0.05). The ratio of Ca / P in both control and treatment groups was also significantly different in every observation day (p<0.05). Conclusion: The addition of aloe vera extract that containing bioactive materials has an effect on increasing levels of mineral elements calcium and calciumphosphorus ratio after immediate implant insertion.

Animals , Dogs , Phosphorus , Spectrum Analysis/methods , Calcium , Aloe , Immediate Dental Implant Loading , Microscopy, Electron, Scanning/methods , Epidemiology, Experimental , Analysis of Variance , Osseointegration , Indonesia
Braz. J. Pharm. Sci. (Online) ; 54(2): e17513, 2018. tab, graf, ilus
Article in English | LILACS | ID: biblio-951937


ABSTRACT Temozolomide is a poorly soluble anti-cancer drug used in the treatment of some brain cancers. Following literature reports about the enhancement of solubility and stability for these kinds of drugs upon complexation with cyclodextrins, we aimed to form an inclusion complex between temozolomide and the different types of cyclodextrins (CDs) to enhance its solubility. In this study, three different cyclodextrins (ß -CD, hydroxyl-ß-CD and γ-CD) were used, and changes in solubility was measured by UV-Vis Spectroscopy and HPLC. Morphological changes upon complexation were shown by the Scanning Electron Microscope (SEM), and weight loss profiles with respect to temperatures which were unique to the compounds were shown by Thermogravimetric Analysis. Changes in heat release profiles were shown by Differential Scanning Calorimeter (DSC). Drug solubility was measured to be increased to around 25% for 1:1 molar ratio for all used CD complexations. Changes of morphology, heat release and weight loss profiles are consistent with the formation of an inclusion complex between CDs and temozolomide. In this study, success was shown in the enhancement of temozolomide solubility upon complexation with different types of CDs. It has been demonstrated that cyclodextrins can be used as complexing agents for poorly soluble anti-cancer drugs, increasing their solubility and hence drug availability

Solubility , Anticarcinogenic Agents/analysis , Cyclodextrins/adverse effects , Pharmaceutical Preparations , Microscopy, Electron, Scanning/methods
Acta odontol. latinoam ; 30(1): 5-12, 2017. ilus, graf
Article in English | LILACS | ID: biblio-907401


The aim of this study was to determine the effect of SDF on thedentin­pulp complex using two models: teeth after SDFapplication (ex vivo) and experimental animal molars. Adescriptive study was performed using two models. In the firstmodel, primary teeth (ex vivo) with enamel­dentin caries, withoutpulp involvement and previously treated with 38% SDF, wereevaluated by means of two techniques: (a) Scanning ElectronMicroscopy (SEM) and energy­dispersive X­ray detector (EDS)to determine qualitative and quantitative composition, and (b)brightfield optical microscopy (OM) after decalcification. Thesecond model used laboratory animal molars from 12 maleWistar rats. Standardized enamel­dentin cavities approximately0.5 mm deep were made the distal fossa of the occlusal face ofboth first lower molars, to one of which a 38% SDF solution wasapplied, while the other was used as a control. Histologicalsections were prepared and dental pulp was evaluatedqualitatively in both groups. SEM on ex vivo teeth showed areasof hypermineralization in the intertubular dentin and few blockedtubules, while EDS detected Ag in the center of the lesion(7.34%), its concentration declining at the edges (1.71%), withnone in the areas farthest from the lesion...

El objetivo del trabajo fue determinar del efecto del DFP encomplejo dentino­pulpar aplicando dos modelos: piezasdentarias luego de su aplicación (ex vivo) y en molares deanimales experimentales. Se realizó un estudio descriptivoaplicando dos modelos: en piezas dentarias primarias (ex vivo)con caries amelodentinarias sin compromiso pulpar que hayansido sometidas previamente con DFP 38%, mediante dosevaluaciones: Microscopía electrónica de Barrido (MEB) ydetector de energía dispersiva de rayos X (EDS) a fin dedeterminar su composición cuali y cuantitativa y Microscopíaóptica de campo claro (MCC) mediante la técnica descalcifi ­cación y en molares de animales de laboratorio donde seutilizaron 12 ratas Wistar macho. La técnica fue estandarizadaen la fosa distal de la cara oclusal del primer molar inferior, serealizó una cavidad amelodentinaria aprox. 0.5 mm de profun ­didad, en ambos molares. En un molar se aplicó la soluciónDFP al 38 % y el opuesto como control. Se realizaron corteshistológicos y se evaluó en forma cualitativa la pulpa dentalen ambos grupos. En las piezas ex vivas mediante MEBse observaron áreas de hipermineralización en la dentinaintertubular y escasos conductillos obliterados y por EDS sedetectó Ag en el centro de la lesión (7.34%), disminuyendo suconcentración en los límites (1,71%) y no se detectó en las zonasmás alejadas de la misma. En MCC se observó DFP sellando losconductillos sólo en sitio de colocación y con una penetraciónlimitada, por debajo, los conductillos se observaron de aspectonormal y el tejido pulpar asociado con la caries tratadaha mostrado un infiltrado inflamatorio crónico y formaciónde dentina terciaria, sin observarse precipitado de Ag...

Humans , Animals , Rats , Dental Pulp , Dentin , Dental Caries/therapy , Dental Pulp/ultrastructure , Diamines/therapeutic use , Molar , Silver Compounds/therapeutic use , Tooth, Deciduous , Decalcification Technique , Epidemiology, Descriptive , Histological Techniques , Microscopy, Electron, Scanning/methods
Rev. Fac. Odontol. (B.Aires) ; 31(70): 5-13, ene.-jun. 2016. ilus, tab, graf
Article in Spanish | LILACS | ID: biblio-835572


Objetivos: El objetivo del presente trabajo fue analizar el nivel de eventos (estiramiento/fractura) en el instumental rotatorio endodonticode niquel- titanio después del uso en Practicas Preclínicas de Grado en dientes ex vivos y tacos de acrílico Materiales y métodos: Seseleccionaron alumnos de grado de la materia Endodoncia de cuatro comisiones (n= 60) que en las pruebas de apropiación deconocimientos y destrezas, superaron el valor de 7/10. A cada alumno se le entregó un kit de ProTaper Universal, nuevo para larealización de dos prácticas: 1° en tacos de acrílicos simuladores de piezas dentarias y 2° en una pieza unirradicular extraída de bajacomplejidad. Se evaluaron las series de limas S1, S2, F1, F2 y F3 en cada población. Se realizó una lectura macro de cada instrumentocon lupa 4X, efectuada por un operador entrenado. Previamente, se realizó en el unaevaluación de los instrumentos sin uso y luego de los estirados o fracturados. Para el análisis de eventos producidos en cada serie de limas seutilizó el Test de Chi cuadrado de homogeneidad con niveles de significación de p= 0,05 (sofware estadístico Infostat) Resultados: No seencontraron diferencias significativas entre las distribuciones de los eventos en dientes y en taco. (Test de Chi2 p=0.0957). En el primeruso, de un total de 300 instrumentos utilizados, 6 sufrieron un evento, siendo en el segundo uso de 270, 12 sufrieron un evento. Para cadainstrumento, las diferencias no resultaron estadísticamente significativas (p valor de Irwin Fisher) S1 p=0.29, S2 p=0.10, F1 p=0.33,F2 p=0.81, F3 p=0.81. Observamos la frecuencia de eventos por instrumento, surgiendo que son más frecuentes los eventos con F1 y F2que con los restantes instrumentos...

Objective: The aim of this study was to analyze the behavior (events: stretching/fracture) of Ni-Ti rotatory Endodontic instruments afterthe utilization in preclinical practice, either ex vivo teeth or acrilic dowels. Materials and methods: undergraduate Endodontic studentsbelonging to four different courses with higher califications (more than 7/10) have been selected (n = 60). Each student has been deliveredwith a brand new ProTaper Universal Kit with the purpose of carrying out two endodontic practices, 1° in acrilics dowels, simulating ateeth and, 2° in a natural low complexity single rooted teeth. The series of files S1, S2, F1, F2 y F3 were assessed in each population. Amacro observation with a 4x magnified lens was performed by a qualified operator. Previously, a MEB observation had been performed onthe brand new instruments and in the post-use stretched or fractured instruments. The Chi square test of homogenity with significancelevels of p = 0.05 have been utilized for the analysis of the events (Infostat Estatistical Software). Results: No significant differences hasbeen found between the event distributions (Teeth/Acrilics dowels) (Test Chi2 p = 0,0957). A total of 300 files used for first time, 6suffered some kind of event, while in the second, a total of 270 files, 12 suffered some kind of event (stretching/fracture). The differenceswere not statistically significant on each file (p = Irwin Fisher value) S1 p=0.29, S2 p=0.10, F1 p=0.33, F2 p=0.81, F3 p=0.81.The event for each instrument has been detected to be more frequent with files F1 and F2 than with other files...

Humans , Male , Female , Dental High-Speed Equipment , Dental Instruments , Education, Predental/methods , Root Canal Preparation/instrumentation , Chi-Square Distribution , Students, Dental/psychology , Models, Educational , Microscopy, Electron, Scanning/methods , Nickel , Shear Strength , Statistical Analysis , Surface Properties , Tensile Strength , Titanium
Braz. j. pharm. sci ; 52(2): 239-250, Apr.-June 2016. tab, graf
Article in English | LILACS | ID: lil-795002


ABSTRACT The objective of this research was to design a new colon-targeted drug delivery system based on chitosan. The properties of the films were studied to obtain useful information about the possible applications of composite films. The composite films were used in a bilayer system to investigate their feasibility as coating materials. Tensile strength, swelling degree, solubility, biodegradation degree, Fourier transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Scanning electron microscope (SEM) investigations showed that the composite film was formed when chitosan and gelatin were jointly reacted jointly. The results showed that a 6:4 blend ratio was the optimal chitosan/gelatin blend ratio. In vitro drug release results indicated that the Eudragit- and chitosan/gelatin-bilayer coating system prevented drug release in simulated intestinal fluid (SIF) and simulated gastric fluid (SGF). However, the drug release from a bilayer-coated tablet in SCF increased over time, and the drug was almost completely released after 24 h. Overall, colon-targeted drug delivery was achieved by using a chitosan/gelatin complex film and a multilayer coating system.

RESUMO O objetivo desta pesquisa foi planejar um novo sistema de liberação de fármacos direcionado ao cólon, utilizando quitosana. Estudaram-se as propriedades dos filmes a fim de obter informações úteis sobre a aplicação desses filmes compósitos. Utilizaram-se os filmes compósitos em sistema de bicamada para investigar a sua viabilidade como materiais de revestimento. Estudos de resistência à tração, grau de intumescimento, solubilidade, grau de biodegradação, no infravermelho por transformada de Fourier (FTIR), de calorimetria diferencial de varredura (DSC) e de microscopia eletrônica de varredura (SEM) mostraram que o filme compósito se formou quando a quitosana e a gelatina reagiram entre si. Os resultados mostraram que a mistura de proporção ótima foi de 6:4 de quitosana:gelatina. Resultados da liberação do fármaco in vitro indicaram que o sistema de revestimento de Eudragit e bicamada de quitosana/gelatina impediu a liberação de fármaco em fluido intestinal simulado (SIF) e em fluido gástrico simulado (SGF). Entretanto, a liberação de fármaco do comprimido revestido em bicamada no SCF aumentou ao longo do tempo e o fármaco foi quase completamente liberado após 24 h. Em geral, se obteve a forma de liberação dirigida ao cólon, utilizando filme complexo de quitosana/gelatina e sistema de revestimento multicamada.

Colon/drug effects , Hydrocortisone/pharmacokinetics , Calorimetry, Differential Scanning/methods , Chitosan/pharmacokinetics , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods , Tablets/pharmacokinetics
Acta cir. bras ; 31(6): 364-370, tab, graf
Article in English | LILACS | ID: lil-785015


ABSTRACT PURPOSE: To compare bone healing in mandibular vertical body osteotomies (MVBO) after fixation with a resorbable 2.0mm-profile fixation system in the first and third postoperative months in rabbits. METHODS: Twenty hemimandibles of ten rabbits were divided into two groups according to duration of resorbable fixation-one or three months. The MVBOs were performed and one four-hole, resorbable, 2.0mm mini-plate fixation system was used on each side. The computed tomography (CT) scans, scanning electron microscopy (SEM), and histomorphometric outcomes of groups I and II were compared. RESULTS: Significant differences were found between the one- and three- month assessments in terms of newly formed bone ratio values (p<0.05). There was more new bone formation at the third month on both the CT and histomorphometric examinations. A better adaptation of the bone tissues to the resorbable mini-plate and screws was observed on SEM at three months. CONCLUSION: The resorbable mini-plates provided a fixation stable enough to allow immediate oral alimentation and callus formation in both groups.

Animals , Female , Rabbits , Wound Healing/physiology , Internal Fixators , Absorbable Implants , Mandibular Osteotomy/rehabilitation , Osteogenesis/physiology , Postoperative Period , Bone and Bones/pathology , Bone and Bones/ultrastructure , Microscopy, Electron, Scanning/methods , Tomography, X-Ray Computed/methods , Bone Remodeling/physiology , Models, Animal , Mandibular Osteotomy/instrumentation
Rev. ADM ; 73(2): 81-87, mar.-abr. 2016. ilus, tab
Article in Spanish | LILACS | ID: lil-789838


Diversos estudios han demostrado mayor o menor grado de afectacióndel esmalte después del uso de los distintos tratamientos para blanqueamiento dental. Por este motivo, se han propuesto varios métodos ytratamientos remineralizantes que pudieran revertir los efectos negativosde dicho tratamiento. El objetivo del presente trabajo fue evaluar el efecto del Opalescence PF 15 por ciento (peróxido de carbamida al 15%) y delremineralizante Flor-Opal (NaF al 1.1 por ciento), ambos de la casa comercialUltradent, así como de la saliva artifi cial sobre la microdureza y la micromorfología del esmalte humano. Se utilizaron 10 incisivos centrales superiores recién extraídos provenientes de centros de salud del Puerto de Veracruz, México. Réplicas de estos dientes fueron obtenidas en lasdiferentes fases del tratamiento de blanqueamiento para ser posteriormente observadas en el microscopio electrónico de barrido (MEB). Asimismo, se realizaron mediciones de microdureza en la superficie del esmalte de los dientes seleccionados durante las diferentes fases del tratamiento de blanqueamiento. Se observó que la microdureza del esmalte se ve disminuida (aunque no significativamente) después de la aplicación del peróxido de carbamida al 15 por ciento, y vuelve a subir después de la aplicación de los remineralizantes, para posteriormente volver a descender siete días después del uso de los mismos. Los datos de microdureza coincidieron con los de micromorfología obtenidos enel MEB. Se concluye que el peróxido de carbamida al 15 opr ciento sí afecta lamicromorfología de la superficie del esmalte, además de que disminuyela microdureza del mismo. Con el uso del remineralizante Flor-Opal se onsiguieron mayores valores de microdureza y mejores características micromorfológicas comparado con la saliva artificial.

Studies have shown varying degrees of involvement of the enamel following the use of tooth-whitening treatments. Consequently, a range of methods and remineralizing treatments have been proposed to reverse their negative effects. The aim of this study was, therefore, to evaluate the effect of Opalescence PF 15% (carbamide peroxide 15%) and the remineralizing treatment Flor-Opal (1.1% NaF), both produced by Ultradent, as well as artifi cial saliva on the microhard-ness and micromorphology of human enamel. Ten recently-extracted central incisors from health centers in the port of Veracruz, Mexico, were used. Replicas of these teeth were made at the various stages of the whitening treatment in order to observe these under a scanning electron microscope (SEM). Microhardness measurements were also taken on the surface of the enamel of the teeth selected at each of the various stages of the whitening treatment. The microhardness of the enamel was found to decrease (though not signifi cantly) after the ap-plication of carbamide peroxide 15%, then increase again following the application of the remineralizing agents, only to decrease again seven days after these were applied. The microhardness data coincided with that for micromorphology obtained from the SEM. We conclude that carbamide peroxide 15% does affect the micromorphology of the enamel surface and also decreases its microhardness. Flor-Opal produced higher microhardness values and better micromorphological characteristics compared to artifi cial saliva.

Humans , Tooth Bleaching/instrumentation , Tooth Bleaching/methods , Dental Enamel/ultrastructure , Tooth Remineralization/instrumentation , Hardness Tests , Materials Testing , Microscopy, Electron, Scanning/methods , Statistical Analysis , Surface Properties
Int. j. odontostomatol. (Print) ; 10(1): 35-40, abr. 2016. ilus
Article in English | LILACS | ID: lil-782619


This study evaluated the cleanliness of post space after different irrigation protocols, associated or not to the use of ultrasound. Thirty-six single-rooted bovine roots were instrumented with rotary system, irrigated with 1 % hypochlorite and filled with Ah Plus sealer and gutta-percha cones. After seven days in stove at 37 °C, two-thirds of canal filling was removed by drilling and the post space preparation was irrigated with 2.5 % NaOCl (group NaOCl); 0.2 % chlorhexidine (group CLX); distilled water (group Water); 2.5 % NaOCl + ultrasound (group NaOCl-US); 0.2 % chlorhexidine + US (Group CLX-US); or water + US (Group Water-US). Roots were cleaved in mesiodistal direction, prepared for scanning electron microscope (SEM) to evaluate the smear layer and debris presence and for energy dispersive spectroscopy (EDS) analyses, to evaluate chemical components of dentin after treatment. The data were subjected to statistical analysis (two-way Anova and Tukey's test 5 %). EDS analysis showed the presence of chemical components of filling material in the samples from all groups. SEM images showed large amount of obliterated dentinal tubules. The use of ultrasound influenced the removal of some components of filling material (p<0.05), but not allowed for total cleaning. It was concluded that none of the irrigating solutions, associated or not to the use of ultrasound were able to completely clean the post space.

Este estudio evaluó la limpieza de la preparación para el espacio de los postes después de diferentes protocolos de irrigación, asociados o no al uso de ultrasonido. Treinta y seis raíces unirradiculares de bovinos fueron instrumentados con sistema rotatorio, irrigadas con un 1 % de hipoclorito y rellenadas con el sellador Ah Plus y conos de gutapercha. Después de siete días en horno a 37 °C, dos tercios de la obturación del canal se removió por perforación y la preparación del espacio para los postes fueron irrigadas con 2,5 % de NaOCl (grupo NaOCl); Clorhexidina 0,2 % (grupo CLX); agua destilada (grupo agua); 2,5 % NaOCl + ultrasonido (grupo NaOCl - US); 0,2 % de clorhexidina + US (Grupo CLX - US); y agua + US (grupo Agua - US). Las raíces se cortaron en dirección mesiodistal y se prepararon para el microscopio electrónico de barrido (MEB) con el fin de evaluar el barrillo dentinario y la presencia de restos; así como mediante el análisis de espectroscopía de energía dispersiva (EDS) para evaluar componentes químicos de la dentina después del tratamiento. Los datos fueron sometidos a análisis estadístico (pruebas ANOVA de dos factores y de Tukey al 5 %). El análisis EDS mostró la presencia de componentes químicos del material de relleno en las muestras de todos los grupos. Imágenes del MEB mostraron gran cantidad de túbulos dentinarios obliterados. El uso de la ultrasonido influyó en la eliminación de algunos de los componentes de material de relleno (p <0,05), pero no permitió la limpieza total. Se concluyó que ninguna de las soluciones de irrigación, asociadas o no a la utilización de los ultrasonidos fueron capaces de limpiar completamente el espacio para los postes.

Animals , Cattle , Root Canal Irrigants , Post and Core Technique , Dentin , Endodontics/methods , Therapeutic Irrigation/methods , Pit and Fissure Sealants , Spectrometry, X-Ray Emission/methods , Ultrasonics , Microscopy, Electron, Scanning/methods , Analysis of Variance
Full dent. sci ; 7(25): 123-129, jan.2016. ilus, tab
Article in Portuguese | LILACS | ID: lil-790088


O objetivo desta pesquisa in vitro foi avaliar a limpeza proporcionada pelo desbridamento no terço apical através da microscopia óptica e de varredura. Para isso, utilizaram-se cinquenta molares inferiores humanos, os quais depois de acessados foram impermeabilizados, esterilizados, contaminados com cepas de Enterococus faecalis (ATCC 29212), durante trinta e cinco dias. Posteriormente foram submetidos ao preparo químico-mecânico com as limas do sistema rotatório Protaper e desbridados com as limas #10 (G1); limas #15 (G2); limas #10 + medicação intracanal - MIC (G3); limas #15 + MIC (G4) e o controle positivo - sem desbridamento e sem MIC - (G5). Em seguida, os espécimes foram avaliados pelos métodos da microscopia óptica (clínica operatória) e microscopia eletrônica de varredura. O teste Kruskal-Wallis mostrou a eficiência do desbridamento, e verificou-se que houve diferença estatisticamente significante (p=0,000) entre os grupos G1 e o G2 no tocante ao aumento da eficácia do desbridamento radicular apical. Quanto às metodologias empregadas, observou-se que ambas são indicadas para avaliar a limpeza proporcionada pelo desbridamento, sendo que as análises através da MCO apresentaram imagens heterogêneas, enquanto a MEV imagens homogêneas. Pode-se concluir que o desbridamento foi eficaz na limpeza do terço apical em molares humanos, porém não houve diferença quanto ao calibre das limas #10 e #15. Os métodos de avaliação da microscopia óptica (clínica operatória) e microscopia eletrônica de varredura foram eficientes em visualizar a limpeza no terço apical...

The aim of this in vitro study was to evaluate the level of cleanliness achieved by debridement of the apical third of root canals by light and scanning microscopy. A total of 50 human mandibular molars were accessed, impermeabilized, sterilized and, subsequently inoculated with a strain of Enterococcus faecalis (ATCC 29212) for 35 days. They were then subjected to chemical-mechanical preparation with the following rotatory Protaper system files: Kerr files #10 (G1) and #15 (G2); Kerr files #10 + intracanal medication - MIC (G3); Kerr files #15 + MIC (G4); and positive controls without debridement or MIC (G5). The apical thirds of the canals were then examined by light clinical microscopy and scanning electron microscopy (SEM). The Kruskal-Wallis test showed the efficiency of the debridement, as verified by statistically significant differences (p=0.000) between groups G1 and G2 with regard to the increase in the effectiveness of the debridement apical radicular. Both light microscopy and SEM were suitable for assessing the cleanliness obtained by debridement. However, while the images seen under the light microscopy were heterogeneous, scanning electron microscopy yielded images that were homogenous. Debridement was efficient for cleansing the apical thirds of canals in human molars, with similar levels of cleanliness achieved with either Kerr files #10 or Kerr files #15. Both clinical microscopy and scanning electron microscopy allowed for adequate visualization for the evaluation of cleanliness in the apical third of the root canal...

Humans , Tooth Apex/anatomy & histology , Molar/anatomy & histology , Debridement/methods , Microscopy, Electron, Scanning/methods , Root Canal Therapy , Odontometry/methods , Statistics, Nonparametric , In Vitro Techniques/methods
Rev. Soc. Odontol. La Plata ; 25(51): 25-31, dic.2015. ilus
Article in Spanish | LILACS | ID: lil-795813


El propósito del trabajo será analizar comparativamente los diversos efectos que producen sobre las restauraciones dentales agentes blanqueadores.El objetivo será valorar los cambios que experimentan en la superficie los materiales de restauración, sometidos a la acción de un agente blanqueador. La metodología utilizada será visualización microscópica electrónica de barrido ambiental. Los resultados obtenidos tendrán transferencia relevante a Insti-tuciones formadoras de recursos humanos en Salud Bucal, al campo profesional odontológico y a empresas o fabricantes para el mejoramiento de su producto...

Dental Amalgam/analysis , Tooth Bleaching/adverse effects , Glass Ionomer Cements/analysis , Hydrogen Peroxide/adverse effects , Composite Resins/analysis , Tooth Bleaching/classification , Bicuspid/ultrastructure , Materials Testing , Microscopy, Electron, Scanning/methods , Molar/ultrastructure , Dental Restoration, Permanent/instrumentation , Surface Properties , Tooth, Nonvital
An. bras. dermatol ; 90(4): 581-584, July-Aug. 2015. ilus
Article in English | LILACS | ID: lil-759212


AbstractSelf-healing collodion baby is a well-established subtype of this condition. We examined a male newborn, who was covered by a collodion membrane. The shed membrane was examined with scanning electron microscopy. The outer surface showed a very compact keratin without the normal elimination of corneocytes. The lateral view of the specimen revealed a very thick, horny layer. The inner surface showed the structure of lower corneocytes with polygonal contour. With higher magnifications villous projections were seen in the cell membrane.

Humans , Infant, Newborn , Male , Ichthyosis, Lamellar/pathology , Microscopy, Electron, Scanning/methods , Keratinocytes/pathology
Rev. ADM ; 72(4): 203-208, jul.-ago. 2015. ilus, tab, graf
Article in Spanish | LILACS | ID: lil-775320


Objetivo: comparar el sellado marginal y la adaptación interna que se obtiene en obturaciones directas mediante técnica convencional con resina de nanorrelleno y técnica de colocación ultrasónica con resinas de baja contracción de polimerización, usando cuatro tipos de adhesivos en preparaciones clase V de dientes extraídos. Material y métodos: Se llevó a cabo un estudio experimental, comparativo y analítico en 32 dientes extraídos a los cuales se les realizó preparaciones clase V de 2 mm oclusogingival, 2 mm mesiodistal y 2 mm de profundidad. Se dividieron en dos grupos; en uno de ellos se obturó empleando técnica convencional y resina de nanorrelleno y en el otro se aplicó una técnica ultrasónica, usando resina de baja contracción. A su vez, cada grupo se subdividió en cuatro, usando diferentes adhesivos (OptiBond all in one Kerr TM , OptiBond Solo Plus Kerr TM , OptiBond FL Kerr TM y OptiBond XTR Kerr TM). Los dientes fueron cortados y analizados al microscopio de barrido (FEI Quanta 200 Scanning Electron Microscope). La información se analizó en el programa SPSS 17.0. Para comparar los grupos de estudio se empleó la prueba U de Mann-Whitney. Resultados: Se encontraron diferencias estadísticamente significativas en el sellado marginal y en la adaptación interna, siendo mejor la técnica de ultrasonido con resina de baja contracción de polimerización (p < 0.05). Con respecto al tipo de adhesivo utilizado, se encontraron diferencias significativas con OptiBond FL TM, el cual tuvo mejor interrelación (p < 0.05)

Objective: To compare the marginal sealing and internal adaptation obtained in direct restorations when using a conventional technique involving nano-filled resin vs. ultrasonic placement using low-polymerization shrinkage resins, and four different types of adhesives in class V preparations on extracted teeth. Material and methods:An experimental, comparative, analytical study was conducted on 32 extracted teeth with class V preparation (2 mmocclusogingival, 2 mm mesiodistal, and 2 mm depth). These were divided into 2 groups: one in which the teeth were restored using a conventional technique with nano-filled resin, and the other, in which an ultrasonic technique using a low-shrinkage resin was employed. In turn, each group was subdivided into 4 groups, in which different KerrTM adhesives were used (OptiBond All-In One, OptiBond Solo Plus, OptiBond FL, and...

Humans , Dental Marginal Adaptation , Dental Bonding/instrumentation , Composite Resins/chemistry , Dental Restoration, Permanent/methods , Ultrasonics/methods , Microscopy, Electron, Scanning/methods , Polymerization/methods , Dental Cavity Preparation/methods , Statistical Analysis , Tooth Extraction
Full dent. sci ; 6(23): 220-225, jul. 2015. tab, ilus, graf
Article in Portuguese | LILACS, BBO | ID: lil-773989


Os sistemas CAD/CAM estão cada vez mais difundidos na área odontológica e vem conquistando uma gama maior de adeptos, desde o seu surgimento há 40 anos, talvez devido às vantagens inerentes ao sistema, que aperfeiçoa o trabalho laboratorial e reduz o tempo clínico do cirurgião dentista. Um dos aspectos mais relevantes para optar-se pela técnica CAD/ CAM, ou pela técnica da cera perdida ou pela técnica slip cast é a adaptação marginal que se consegue obter quando da confecção da peça protética. A ocorrência de falhas altera a longevidade do trabalho protético, assim como a do elemento dentário remanescente. Esta revisão tem por objetivo comparar a adaptação cervical de coroas totais confeccionadas por sistemas CAD/CAM com coroas totais confeccionadas pela técnica da cera perdida ou pela técnica slip cast. Foram selecionados e analisados 22 artigos nas bases de dados Pubmed e Scielo, nos quais 12 sistemas de CAD/CAM diferentes foram encontrados. Variáveis como próteses múltiplas x unitárias, tipo de preparo, estrutura, ajuste interno, cimentação e método de avaliação de adaptação marginal foram analisadas. Na maioria dos artigos revisados houve uma grande discrepância entre as desadaptações com métodos semelhantes variando entre 9µm (Sistema Pocera-Nobel Biocare) e 192 µm (Sistema Cerec-Sirona). Um gap marginal de 56,55 µm (Cerec-Sirona) foi encontrado em outro estudo, usando uma metodologia diferente. Entende-se que mais estudos, com uma metodologia padronizada, devem ser realizados.

The CAD/CAM systems are becoming increasingly widespread in Dentistry and have gained a wider range of fans, from its inception 40 years ago, perhaps due to the advantages inherent in the system, which optimizes the laboratory work and reduces clinical time of the dentist. One of the most relevant aspects to choose the CAD/CAM technique or the technique of lost wax or slip cast by technical aspects is marginal fit obtained. The occurrence of failures on the marginal fit compromises the longevity of prosthetic work, as well as the remaining tooth. This review aims to compare the cervical adaptation of crowns made by CAD/CAM systems with crowns made by the lost wax technique by technique or slip cast. A search was performed in Pubmed and SciELO databases and 22 articles were selected and analyzed, and 12 different CAD/CAM systems were found. Variables such as multiple vs. single prostheses, type of preparation, structure, internal adjustment, cementation and method applied to assess marginal adaptation were analyzed. Most papers registered a large discrepancy between the mismatches with similar methods ranging from 9µm (Pocera-Nobel Biocare System) to 192 µm (Sirona-Cerec System). A marginal gap 56.55 µm (Sirona-Cerec) was found in another study using a different methodology. It is understood that further studies with a standardized methodology should be performed.

Tooth Crown , Dental Marginal Adaptation , Microscopy, Electron, Scanning/methods , Prosthesis Fitting , Computer-Aided Design/instrumentation , Denture, Partial, Fixed , Cementation
Rev. argent. microbiol ; 47(2): 143-147, June 2015.
Article in Spanish | LILACS | ID: biblio-1147321


La pudrición carbonosa, causada por Macrophomina phaseolina, es una enfermedad importante de la caña de azúcar en México. Este estudio se realizó con el objetivo de caracterizar aislados de M. phaseolina obtenidos de caña de azúcar mediante análisis morfológicos y moleculares. La caracterización morfológica de 10 aislados se llevó a cabo con el uso de microscopia electrónica de barrido y microscopia de luz. Para confirmar la identificación, se extrajo el ADNr de 2 aislados representativos, y la región del espaciador interno transcrito (ITS) se amplificó mediante la reacción en cadena de la polimerasa y se secuenció usando los iniciadores específicos MpKF1 y MpKR1. Los aislados se identificaron como M. phaseolina con base en la morfología. El análisis de secuencias ITS mostró 100% de similitud con las secuencias de M. phaseolina depositadas en el GenBank. Para nuestro conocimiento, este es el primer estudio del mundo enfocado a caracterizar aislados de M. phaseolina obtenidos de caña de azúcar

Charcoal rot caused by Macrophomina phaseolina is an important disease of sugarcane in Mexico. This study was carried out to characterize isolates of M. phaseolina obtained from sugarcane by the combination of morphological and molecular analyses. The morphological characterization of 10 isolates was performed using scanning electron microscopy and light microscopy. To confirm the morphological identification, rDNA from two representative isolates was extracted, and the internal transcribed spacer (ITS) region was amplified by polymerase chain reaction and sequenced using specific primers MpKF1 and MpKR1. Based on their morphological characteristics, all isolates were identified as M. phaseolina. Moreover, the analysis of two ITS sequences showed 100% similarity with the M. phaseolina sequences deposited in the GenBank. To our knowledge, this is the first study in the world aimed at characterizing isolates of M. phaseolina obtained from sugarcane

Microscopy, Electron, Scanning/methods , Saccharum/microbiology , Microscopy/methods , Saccharum/growth & development