scholarly journals THE POTENTIAL OF SEVERAL FLUORIDE-BASED VARNISHES AS REMINERALIZATION AGENTS: MORPHOLOGICAL STUDIES, DENTIN SURFACE HARDNESS, AND CRYSTALLINITY TESTS

2018 ◽  
Vol 9 ◽  
pp. 60 ◽  
Author(s):  
Sri Angky Soekanto ◽  
Fadiza Fadillah ◽  
Putri Nuraisiya ◽  
Ferry Gultom ◽  
Agoeng T Sarwono
Keyword(s):  
Surface Hardness ◽  
Amorphous Layer ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Metal Compounds ◽  
Treatment Groups ◽  
Dentin Surface ◽  
Morphological Studies ◽  
Ph Cycling ◽  
Calcium Compounds

Objectives: This study was conducted to analyze the effects of several fluoride-based varnishes: Sodium diamine fluoride (SDF), nanosilver fluoride (NSF), and propolis fluoride (PPF). Fluoride-based varnish is proven to remineralize and arrest caries progression with minimal side effects. SDF, the gold standard for this study, compared to NSF and PPF to observe the dentin morphology, hardness, and crystallinity test.Methods: Dentin blocks were allocated and divided into control groups and treatment groups with SDF (38%), NSF (3.16%, 3.66%, and 4.16%), and PPF (3%, 6%, and 10%). The dentin discs were demineralized using a demineralization solution (pH 4.4) for 96 h. Each dentin disc in the treatment group received a topical application of various fluoride-based varnishes and was then subjected to pH cycling for 8 days. The surface morphology of dentin was observed by a scanning electron micrograph (SEM), dentin hardness was analyzed by a Vickers microhardness tester, and the crystal characteristics of dentin blocks were investigated by X-ray diffraction (XRD).Results: This study showed crystal fluorapatite on the dentin surface of SDF and NSF. There was an amorphous layer on the dentin surface of PPF (10%) detected when using SEM. The Vickers hardness number of dentin increased after the application of SDF, NSF, and PPF. XRD revealed precipitates of apatite compounds, calcium compounds, and metal compounds in the treatment groups in higher concentrations than in the control (demineralized) group.Conclusion: It was concluded that SDF, NSF, and PPF were effective for dentin remineralization. Hence, NSF and PPF fluoride-based varnishes are promising as anticariogenic agents.

scholarly journals Anticaries Potential of Low Fluoride Dentifrices Found in The Brazilian Market

2016 ◽  
Vol 27 (3) ◽  
pp. 298-302 ◽  
Author(s):  
Adriana de Cássia Ortiz ◽  
Livia Maria Andaló Tenuta ◽  
Cínthia Pereira Machado Tabchoury ◽  
Jaime Aparecido Cury
Keyword(s):  
Surface Hardness ◽  
Positive Control ◽  
Negative Control ◽  
Low Ph ◽  
Treatment Groups ◽  
Enamel Demineralization ◽  
Ph Cycling

Abstract Low-fluoride (F) dentifrices (<600 µg F/g) are widely available worldwide, but evidence to recommend the use of such dentifrices, with either regular or improved formulations, is still lacking. Therefore, the aim of this study was to evaluate the anticaries potential of low-F dentifrices found in the Brazilian market, using a validated and tested pH-cycling model. Enamel blocks were selected by surface hardness (SH) and randomized into four treatment groups (n=12): non-F dentifrice (negative control), low-F dentifrice (500 μg F/g), low-F acidulated dentifrice (550 μg F/g) and 1,100 μg F/g dentifrice (positive control). The blocks were subjected to pH-cycling regimen for 8 days and were treated 2x/day with dentifrice slurries prepared in water (1:3, w/v). The pH of the slurries was checked, and only the acidulated one had low pH. After the pH cycling, SH was again determined and the percentage of surface hardness loss was calculated as indicator of demineralization. Loosely- and firmly-bound F concentrations in enamel were also determined. The 1,100 μg F/g dentifrice was more effective than the low-F ones to reduce enamel demineralization and was the only one that differed from the non-F (p<0.05). All F dentifrices formed higher concentration of loosely-bound F on enamel than the non-F (p<0.05), but the 1,100 μg F/g was the only one that differed from the non-F in the ability to form firmly-bound F. The findings suggest that the low-F dentifrices available in the Brazilian market, irrespective of their formulation, do not have anticaries potential.

scholarly journals COMPARISON OF THE POTENCY OF SEVERAL FLUORIDE-BASED VARNISHES AS AN ANTICARIOGENIC ON CALCIUM, PHOSPHATE, AND FLUORIDE ION LEVELS

2018 ◽  
Vol 9 ◽  
pp. 55 ◽  
Author(s):  
Sri Angky Soekanto ◽  
Namira Rosithahakiki ◽  
Dewi Fatma Suniarti ◽  
Mohamad Sahlan
Keyword(s):  
Calcium Phosphate ◽  
Solution Ph ◽  
Fluoride Ions ◽  
Silver Diamine Fluoride ◽  
Treatment Groups ◽  
Phosphate Ions ◽  
Human Dentin ◽  
Golden Standard ◽  
Ph Cycling ◽  
Caries Progression

Objectives: The purpose of this present study was to analyze several fluoride-based varnishes: Silver diamine fluoride (SDF), nanosilver fluoride (NSF), and propolis fluoride (PPF). Fluoride-based varnish is proven to act as antibacterial and remineralization agents that arrested caries progression with minimal side effects. SDF, the golden standard for this study, was compared to NSF and PPF, which were made in our own laboratory, to evaluate their ability to release calcium, phosphate, and fluoride ions and act as anticariogenic agents.Methods: Human dentin discs were prepared and divided into control groups and treatment groups with SDF (38%), NSF (3.16%, 3.66%, and 4.16%), and PPF (3%, 6%, and 10%). The dentin discs were demineralized using a demineralization solution (pH 4.4) for 96 h. Each dentin disc in the treatment group received a topical application of various fluoride-based varnishes and then was subjected to pH-cycling for 8 days. The quantity of calcium, phosphate, and fluoride ions on the dentin discs surface was compared after being detected using energy dispersive X-ray spectroscopy.Results: The result revealed that the calcium ion levels in groups NSF and PPF increased significantly compared to SDF. The levels of phosphate ions and fluoride ions in groups NSF and PPF increased significantly compared to SDF.Conclusion: The study concluded that, in contrast to SDF, the prepared NSF and PPF fluoride-based varnishes were shown to release calcium, phosphate, and fluoride ions in this study. Hence, NSF and PPF fluoride-based varnishes are promising as anticariogenic agents.

scholarly journals Dual Electrochemical Treatments to Improve Properties of Ti6Al4V Alloy

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2479
Author(s):  
Stefano Rossi ◽  
Luciana Volgare ◽  
Carine Perrin-Pellegrino ◽  
Carine Chassigneux ◽  
Erick Dousset ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Combined Treatment ◽  
Amorphous Film ◽  
Amorphous Layer ◽  
Good Alternative ◽  
Surface Treatments ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Fluid Environment

Surface treatments are considered as a good alternative to increase biocompatibility and the lifetime of Ti-based alloys used for implants in the human body. The present research reports the comparison of bare and modified Ti6Al4V substrates on hydrophilicity and corrosion resistance properties in body fluid environment at 37 °C. Several surface treatments were conducted separately to obtain either a porous oxide layer using nanostructuration (N) in ethylene glycol containing fluoride solution, or bulk oxide thin films through heat treatment at 450 °C for 3 h (HT), or electrochemical oxidation at 1 V for 3 h (EO), as well as combined treatments (N-HT and N-EO). In-situ X-ray diffraction and ex-situ transmission electron microscopy have shown that heat treatment gave first rise to the formation of a 30 nm thick amorphous layer which crystallized in rutile around 620 °C. Electrochemical oxidations gave rise to a 10 nm thick amorphous film on the top of the surface (EO) or below the amorphous nanotube layer (N-EO). Dual treated samples presented similar results with a more stable behavior for N-EO. Finally, for both corrosion and hydrophilicity points of view, the new combined treatment to get a total amorphous N-EO sample seems to be the best and even better than the partially crystallized N-HT sample.

Photoluminescence Enhancement of CdS Nanocrystals Fabricated on Dithiocarbamate Functionalized PET Substrates

2012 ◽  
Vol 512-515 ◽  
pp. 1511-1515
Author(s):  
Chun Lin Zhao ◽  
Li Xing ◽  
Xiao Hong Liang ◽  
Jun Hui Xiang ◽  
Fu Shi Zhang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Hexagonal Structure ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Cds Nanocrystals ◽  
Morphological Studies ◽  
Transmission Electron

Cadmium sulfide (CdS) nanocrystals (NCs) were self-assembled and in-situ immobilized on the dithiocarbamate (DTCs)-functionalized polyethylene glycol terephthalate (PET) substrates between the organic (carbon disulfide diffused in n-hexane) –aqueous (ethylenediamine and Cd2+ dissolved in water) interface at room temperature. Powder X-ray diffraction measurement revealed the hexagonal structure of CdS nanocrystals. Morphological studies performed by scanning electron microscopy (SEM) and high-resolution transmission electron microscope (HRTEM) showed the island-like structure of CdS nanocrystals on PET substrates, as well as energy-dispersive X-ray spectroscopy (EDS) confirmed the stoichiometries of CdS nanocrystals. The optical properties of DTCs modified CdS nanocrystals were thoroughly investigated by ultraviolet-visible absorption spectroscopy (UV-vis) and fluorescence spectroscopy. The as-prepared DTCs present intrinsic hydrophobicity and strong affinity for CdS nanocrystals.

scholarly journals Y3+ substituted Sr-hexaferrites: sol-gel synthesis, structural, magnetic and electrical characterization

Cerâmica ◽  
2019 ◽  
Vol 65 (374) ◽  
pp. 274-281 ◽  
Author(s):  
S. S. Satpute ◽  
S. R. Wadgane ◽  
S. R. Kadam ◽  
D. R. Mane ◽  
R. H. Kadam
Keyword(s):  
Electron Microscopy ◽  
Sol Gel ◽  
Electrical Characterization ◽  
Combustion Method ◽  
Hexagonal Structure ◽  
Strontium Hexaferrite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
Auto Combustion

Abstract Y3+ substituted strontium hexaferrites having chemical composition SrYxFe12-xO19 (x= 0.0, 0.5, 1.0, 1.5) were successfully synthesized by sol-gel auto-combustion method. The structural and morphological studies of prepared samples were investigated by using X-ray diffraction technique, energy dispersive X-ray spectroscopy, field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy. The X-ray diffraction pattern confirmed the single-phase hexagonal structure of yttrium substituted strontium ferrite and the lattice parameters a and c increased with the substitution of Y3+ ions. The crystallite size also varied with x content from 60 to 80 nm. The morphology was studied by FE-SEM, and the grain size of nanoparticles ranged from 44 to 130 nm. The magnetic properties were investigated by using vibrating sample magnetometer. The value of saturation magnetization decreased from 49.60 to 35.40 emu/g. The dielectric constant decreased non-linearly whereas the electrical dc resistivity increased with the yttrium concentration in strontium hexaferrite.

scholarly journals Synthesis of Polymer-Based Magnetic Nanocomposite for Multi-Pollutants Removal from Water

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1742
Author(s):  
Fatimah Mohammed Alzahrani ◽  
Norah Salem Alsaiari ◽  
Khadijah Mohammedsaleh Katubi ◽  
Abdelfattah Amari ◽  
Faouzi Ben Rebah ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Magnetic Composite ◽  
Sample Treatment ◽  
Water Type ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Vibration Sample Magnetometer ◽  
Pollutants Removal ◽  
Co Precipitation ◽  
Red Dye

A magnetic polymer-based nanocomposite was fabricated by the modification of an Fe3O4/SiO2 magnetic composite with polypyrrole (PPy) via co-precipitation polymerization to form PPy/Fe3O4/SiO2 for the removal of Congo red dye (CR) and hexavalent chromium Cr(VI) ions from water. The nanocomposite was characterized using various techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), vibration sample magnetometer, and thermogravimetric analysis (TGA). The results confirm the successful fabrication of the nanocomposite in the size of nanometers. The effect of different conditions such as the contact time, adsorbent dosage, solution pH, and initial concentration on the adsorption process was investigated. The adsorption isotherm suggested monolayer adsorption of both contaminants over the PPy/Fe3O4/SiO2 nanocomposite following a Langmuir isotherm, with maximum adsorption of 361 and 298 mg.g−1 for CR dye and Cr(VI), respectively. Furthermore, the effect of water type on the adsorption process was examined, indicating the applicability of the PPy/Fe3O4/SiO2 nanocomposite for real sample treatment. Interestingly, the reusability of the nanocomposite for the removal of the studied contaminants was investigated with good results even after six successive cycles. All results make this nanocomposite a promising material for water treatment.

Monitoring of Fluctuations in the Physical and Chemical Properties of a High-Calcium Fly Ash

1987 ◽  
Vol 113 ◽  
Author(s):  
Scott Schlorholtz ◽  
Ken Bergeson ◽  
Turgut Demirel
Keyword(s):  
Fly Ash ◽  
Chemical Properties ◽  
Operating Conditions ◽  
Physical And Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
High Calcium ◽  
Physical And Chemical ◽  
And Chemical Properties

ABSTRACTThe physical and chemical properties of fly ash produced at Ottumwa Generating Station have been monitored since April, 1985. The fly ash is produced from burning a low sulfur, sub-bituminous coal obtained from the Powder River Basin near Gillette, Wyoming. One-hundred and sixty samples of fly ash were obtained during the two year period. All of the samples were subjected to physical testing as specified by ASTM C 311. About one-hundred of the samples were also subjected to a series of tests designed to monitor the self-cementing properties of the fly ash. Many of the fly ash samples were subjected to x-ray diffraction and fluorescence analysis to define the mineralogical and chemical composition of the bulk fly ash as a function of sampling date. Hydration products in selected hardened fly ash pastes, were studied by x-ray diffraction and scanning electron microscopy. The studies indicated that power plant operating conditions influenced the compressive strength of the fly ash paste specimens. Mineralogical and morphological studies of the fly ash pastes indicated that stratlingite formation occurred in the highstrength specimens, while ettringite was the major hydration product evident in the low-strength specimens.

Synthesis, Structural, Morphological and I-V Characteristics of Polyaniline-MgCl Composite

2022 ◽  
Vol 1048 ◽  
pp. 141-146
Author(s):  
Madihally Nagaraja ◽  
Geetha Thippeswamy ◽  
Sushma Prashanth ◽  
Jayadev Pattar ◽  
Mahesh Hampapatna Mahesh
Keyword(s):  
Structural Analysis ◽  
Oxidative Polymerization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sem Micrographs ◽  
Morphological Studies ◽  
Current Voltage ◽  
Amorphous Nature ◽  
Diffraction Patterns ◽  
Polymerization Method

Composite of polyaniline-MgCl has been synthesized using oxidative polymerization method. Synthesized samples were characterized for structural analysis using FTIR and XRD. Morphological studies were carried by SEM micrographs. Current-Voltage (I-V) properties are obtained through Kiethly source meter. FTIR spectrum of polyaniline-MgCl composite indicates all the characteristic peaks of polyaniline. X-ray diffraction patterns represented the amorphous nature of polyaniline-MgCl composite. SEM micrographs confirmed the presence of MgCl particles in polyaniline matrix. I-V characteristics have shown the ohmic type behavior of polyaniline and polyaniline-MgCl composite.

The Potential of a Bioactive, Pre-reacted, Glass-Ionomer Filler Resin Composite to Inhibit the Demineralization of Enamel in Vitro

2021 ◽  
Vol 46 (1) ◽  
pp. E11-E20
Author(s):  
IF Leão ◽  
N Araújo ◽  
CK Scotti ◽  
RFL Mondelli ◽  
MM de Amoêdo Campos Velo ◽  
...  
Keyword(s):  
Resin Composite ◽  
Surface Hardness ◽  
Composition Analysis ◽  
Glass Ionomer ◽  
Material Interface ◽  
Enamel Demineralization ◽  
Restorative Materials ◽  
Ph Cycling ◽  
Group B

Clinical Relevance A prereacted, glass-ionomer filler fluoride-containing resin composite had lower remineralization potential than glass-ionomer cements but was able to inhibit enamel demineralization; thus, it may be an option for restoring dental surfaces for patients at high risk of caries. SUMMARY Evidence is lacking on the use of surface prereacted glass-ionomer filler resin composites to inhibit demineralization and that simulate real clinical conditions. The present laboratory study evaluated the potential of such composites to prevent demineralization and quantified fluoride (F) and other ions released from restorative materials after a dynamic pH-cycling regimen applied to the tooth material interface in vitro. The pH-cycling regimen was assessed by measuring surface hardness (SH) along with energy dispersive X-ray spectroscopy (EDX). Methods and Materials: Ninety blocks of bovine enamel were subjected to composition analysis with EDX, and were further categorized based on SH. The blocks were randomly divided into 6 treatment groups (n=15 each): F IX (Fuji IX Extra; GC Corporation); IZ (Ion Z, FGM); F II (Fuji II LC, GC Corporation); B II (Beautifil II, Shofu); F250 (Filtek Z250 XT, 3M ESPE); and NT (control, no treatment). The blocks were subjected to a dynamic pH-cycling regimen at 37°C for 7 days concurrently with daily alternations of immersion in demineralizing/remineralizing solutions. EDX was conducted and a final SH was determined at standard distances from the restorative materials (150, 300, and 400 μm). Results: The EDX findings revealed a significant increase in F concentration and a decrease in Ca2+ in the enamel blocks of group B II after the pH-cycling regimen (p&lt;0.05). SH values for groups F IX, IZ, and F II were greater than those for groups B II, F250, and NT at all distances from the materials. Conclusions: The results suggest that each of 3 restorative materials, F IX, IZ, and F II, partially inhibited enamel demineralization under a dynamic pH-cycling regimen.

Effect of Coating Bath Parameters on Properties of Electroless Nickel-Boron Alloy Coatings

2022 ◽  
Vol 10 (1) ◽  
pp. 0-0
Keyword(s):  
Surface Roughness ◽  
Surface Hardness ◽  
Chloride Concentration ◽  
Electroless Nickel ◽  
Nickel Chloride ◽  
Scratch Test ◽  
X Ray Diffraction ◽  
Tribological Behaviour ◽  
Pin On Disc ◽  
Mechanical Behaviours

Electroless nickel-boron binary coatings were obtained with various bath compositions to investigate the effect of bath parameters on tribological and mechanical behaviours of the coating. Characterisation of the coating for surface morphology and phase structure is done using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD), respectively, whereas tribological behaviour of coatings is evaluated on a pin-on-disc tribo-tester. Elastic modulus and surface hardness of coatings have been obtained using nano-indentation technique, while the scratch behaviour of the coatings has been determined using micro-scratch test. Corrosion resistance of coatings is also determined. It is observed that surface roughness of the coatings increased with increase in sodium borohydride concentration but decreased slightly with increase in nickel chloride concentration. Friction and wear characteristics are found to increase with surface roughness which occurs due to increased boron content. Surface hardness and scratch hardness are also seen to vary with coating bath parameters.

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