In vitro Evaluation of Enamel Surface Treated with Fluoride After Bleaching and Etching Erosive Processes

2018 ◽  
Vol 69 (7) ◽  
pp. 1714-1717
Author(s):  
Roxana Ionela Vasluianu ◽  
Norina Consuela Forna ◽  
Elena Raluca Baciu ◽  
Mirela Zaltariov ◽  
Lavinia Vasiliu ◽  
...  

The anti-erosion effect of fluoride on the enamel surface was investigated by ATR-FTIR, SEM and EDX techniques. Four extracted teeth (two incisors and two premolars) were initially bleached with carabamide peroxide and etched with ortho-phosphoric acid then fluoride treatment was applied. Significant differences in enamel composition and morphology were observed providing the effect of fluoride application in remineralization of teeth. Infrared spectroscopy was employed to probe the changes in enamel structure. Scanning electron microscopy/energy dispersive X-ray spectroscopy analysis revealed higher content in F of teeth enamel. Morphology changes revealed a re-mineralization of enamel surface after the treatment with fluoride gel.

Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.


2015 ◽  
Vol 638 ◽  
pp. 67-72
Author(s):  
Ana Maria Salantiu ◽  
Florin Popa ◽  
Petru Pascuta ◽  
Olga Soritau ◽  
Noemi Dirzu ◽  
...  

This work aims to investigate the influence of surface conditioning of porous Ti for enhancing its biological activity, as assessed by in vitro stem cell testing. Porous Ti samples with an average porosity of 32% were processed by Powder Metallurgy with dextrin as a space holder. The samples were subjected to H2O2 treatment to form an enhanced TiO2 film, followed by a heat treatment at 400°C and 600°C aiming to the crystallization of the as-formed amorphous titanium oxide. Samples characterization was performed by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD). The treated surfaces revealed to be made of both anatase and rutile TiO2, with groove–shaped structure and cracks on the surface of the TiO2 film. The intrinsic biocompatibility of the chemically modified porous Ti surfaces was assessed in vitro. In our cell culture tests, stem cells were found to attach and proliferate better on the chemically treated Ti surfaces compared to the control untreated Ti surfaces.


Author(s):  
M. Shah ◽  
D. Patel

Oxcarbazepine has low solubility and low oral bioavailability, so it’s a challenge to formulate suitable dosage form. In this present investigation, to improve the dissolution rate and solubility, skimmed milk is used as a carrier. Physical mixers were prepared using various drugs to carrier ratio and spray drying technology was used to develop solid dispersion with the carrier. Various techniques were used to characterize the solid dispersion immediately after they were made which includes differential scanning calorimetry, scanning electron microscopy, fourier transform infra- red spectroscopy, X-ray diffraction and in-vitro dissolution profiles. The differential scanning calorimetry thermograms of raw drug indicated of its anhydrous crystalline nature. In thermograms of solid dispersion, the characteristic peak was absent suggesting the change from crystalline nature to amorphous form. X-ray diffraction confirmed those results. X-ray diffraction results of raw drug showed highly intense peak characteristic of its crystalline nature where solid dispersion showed less intense, more diffused peak indicating the change in crystalline form. Fourier transforms infra-red spectroscopy studies showed there was no interaction between drug and carrier. Scanning electron microscopy support the amorphous nature of mixer. The whole formulation showed distinct enhancement in the drug release behavior and solubility. The optimum oxcarbazepine to skimmed milk ratio 1:3 enhances the in-vitro drug release by 3.5 fold and also show distinct increase in solubility. It was concluded that for improvement of solubility of poorly water soluble oxcarbazepine, skimmed milk powder as a carrier can be utilize very well.


2006 ◽  
Vol 514-516 ◽  
pp. 985-989
Author(s):  
B.J.M. Leite Ferreira ◽  
M.G.G.M. Duarte ◽  
M. Helena Gil ◽  
Rui N. Correia ◽  
J. Román ◽  
...  

Two materials with potential application in bone tissue repair have been developed: 1) a non-biodegradable composite based in a new methacrylic-co-acrylic matrix; and 2) a biodegradable composite based in a chitosan (Ch) matrix. Both matrices were reinforced with glass-ceramic particles of composition (mol%) 70 SiO2 – 30 CaO. The in vitro bioactivity of composites was assessed by soaking in simulated body fluid (SBF) for periods of up to 7 days at 37º C. X-ray diffraction (XRD) and scanning electron microscopy coupled with X-ray energy dispersive spectroscopy (SEM-EDS) were used for deposit identification after different soaking periods. Calcium phosphate particulate deposits were detected after 3 days of immersion, followed by growth and maturation towards apatite.


2013 ◽  
Vol 38 (6) ◽  
pp. E201-E209 ◽  
Author(s):  
DC Salazar ◽  
J Dennison ◽  
P Yaman

SUMMARY This study determined the filler content by weight percentage of four resin composites and examined the morphology, size, and elemental distribution of the filler particles. Four commercially available light-cured resin composites were evaluated for filler content by weight using ashing in air and acetone dissolution techniques. Ten specimens were analyzed for each material and technique. Specimens for ashing were heated to 650°C for 30 minutes. For the acetone dilution, the uncured specimens were dissolved, centrifuged, and decanted. In addition, scanning electron microscopy evaluation and energy dispersive x-ray spectroscopy analysis were performed to determine morphologic characteristics and elemental distribution, respectively. Filler percentages by weight for Aelite LS, Filtek LS, IPS Empress Direct, and Kalore from ashed in air were 86.44%, 77.86%, 72.17%, and 70.62%, and from acetone dissolution percentages were 85.05%, 75.56%, 78.88%, and 77.73%, respectively. Aelite LS had significantly higher filler content for both techniques. Kalore had significantly lower filler content for the ashing technique (70.62%), and Filtek LS had significantly lower filler content for the acetone dissolution technique (75.55%). Manufacturer reported filler content for Aelite LS (88%) and Filtek LS (76%) approximated the study results for both techniques, while Kalore (82%) and IPS Empress Direct (79%) were only similar for acetone dissolution, indicating higher content of prepolymerized particles. Morphologic examination showed spherical shaped particles for Aelite LS and splintered and irregular shaped particles for all other materials. Aelite LS had the highest filler content for both techniques. Values for filler content by weight using the acetone dissolution were closer to manufacturer reported values.


1984 ◽  
Vol 62 (6) ◽  
pp. 1116-1121 ◽  
Author(s):  
F. Lapeyrie ◽  
Monique Perrin ◽  
R. Pepin ◽  
G. Bruchet

Several forms of extracellular crystals have been observed in vitro on a semisynthetic culture medium. The conditions for their formation have not been determined. Their morphology and their localisation on the hyphal surface and in the culture medium have been investigated by means of scanning electron microscopy. These crystals have been identified as dehydrated calcium oxalate (Weddellite) using x-ray diffraction methods. Their high calcium content has been demonstrated with the scanning electron microprobe, by detecting the x-ray emission of calcium. The significance of calcium oxalate production by an ectomycorrhizal fungus is discussed.


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