Search results for "fluoride"
showing 10 items of 314 documents
Comparative analysis of the remineralization potential of CPP–ACP with Fluoride, Tri-Calcium Phosphate and Nano Hydroxyapatite using SEM/EDX – An in …
2019
Background In recent years, the non-invasive management of non cavitated caries lesions using remineralization systems to repair the enamel have received more attention from the scientific community. Aim: To quantitatively evaluate the remineralization potential of Casein phosphopeptide-amorphous calcium phosphate-fluoride(CPP-ACPF), Tri-calcium phosphate(TCP) & Nano-hydroxyapatite(nHAP) using Scanning Electron Microscopy(SEM) and Energy dispersive X-ray Analysis(EDX). Material and Methods 40 enamel specimens were prepared, and immersed in demineralising solution at a pH of 4.4 for 96 hours at 37°C, to induce artificial carious lesions. Remineralization was carried out for a period of 30 da…
Cytotoxicity investigations of plasma sprayed calcium phosphate coatings
1994
One potential alternative material to replace hydroxyapatite (HAp) as a coating material for plasma-sprayed coatings on implants for hip replacement is fluorapatite (FAp). FAp has advantages over HAp regarding the capability of being chemically stable during the coating process. This leads to surface coatings containing high apatite rates with a mechanical stability (bond strength, microhardness) comparable to HAp. From the technical point of view the production of FAp coatings is well investigated, although studies on biocompatibility of FAp coatings are fewer. This paper reports the production of HAp and FAp coatings with varying solubilities by plasma spraying and their in vitro cytotoxi…
Copolymerization of Vinylidene Fluoride and Acrylic Acid in Supercritical Carbon Dioxide
2010
The free-radical copolymerization of vinylidene fluoride (VDF) and acrylic acid (AA) was carried out in supercritical carbon dioxide using both precipitation and dispersion techniques in the presence of an ammonium carboxylate perfluoropolyether compound. Formation of a copolymer was confirmed by variable contact time CP MAS NMR spectroscopy. Macromolecular matrices were significantly enriched in AA with respect to the initial feed composition and we found that the nonfluorinated monomer has a much higher reactivity ratio with respect to VDF. The cumulative concentration, crystallinity, and water affinity of the synthesized copolymers could be modified changing the initial feed composition,…
Interaction of fluoride ions with milk proteins studied by gel filtration
1992
The interaction of fluoride ions with the bovine milk protein a-lactalbumin, type 1 a-casein, (3-casein, and K-casein was studied at pH 6.6, 5.5 and 3.9. At pH 6.6 and 5.5 fluoride ions do not combine with any of these protein. However, at pH 3.9 they combine with a-lactalbumin.
National Italian Guidelines for caries prevention in 0 to 12 years-old children
2007
Abstract AIM: Oral and dental health improved tremendously over the last fifty years in Italy but still prevalence of dental caries in children remains a significant clinical problem. This report describes the National Italian Guidelines for caries prevention. METHODOLOGY: A panel of experts coordinated by the Italian Society of Paediatric Dentistry (SIOI) planned to elaborate the national Italian guidelines for caries prevention in children. The structure of the guidelines has been planned to follow the principles of modern caries treatment and management as well as science based dentistry. The main procedure was based on a hierarchic evaluation of literature. CONCLUSION: The guidelines ar…
A christmas gift: Signature of the 24th December 2018 eruption of Mt. Etna on the chemical composition of bulk deposition in eastern sicily
2020
The eruption of Mt. Etna which occurred on December 24th 2018 was characterized by strombolian activity and fire fountains, emitted by the New South-East Crater and along a fissure that propagated towards the SE. The influence of volcanic emissions on atmospheric deposition was clearly detectable at several kilometres from the source. Wet and dry (bulk) deposition samples were collected each month, through a network of eleven collectors, in the areas of Milazzo, and Priolo between June 2018 and June 2019. They were analysed for major ions and trace elements concentrations. The pH values range from 3.9 to 8.3, while the EC values range from 7 to 396 μS cm-1. An extensive neutralization of th…
Calcium Pre-Rinse: Effect on permeability of dentin tubules by fluoride rinse
2019
Background The aim of this study was to evaluate whether calcium (CaL) solution would enhance the capacity of sodium fluoride (NaF) solution in reducing the permeability of hypersensitive dentin. Material and Methods Thirty-two Wistar rats ingested for 45 days acidic isotonic drink (Gatorade, pH 2.7) ad libitum to induce dental erosion. Then, molar teeth received a cold stimulus to confirm the presence and score the intensity of dentin hypersensitivity based on body contraction and noise. Animals were allocated to four groups (n=8), according to the solution(s) applied in the oral cavity: NaF (12 mmol/L, 1 min); CaL (150 mmol/L, 1 min); CaL followed by NaF (CaF+NaF, 1 min each); distilled w…
UraniumIV and uranyle salts, efficient and reusable catalysts for acylation of aromatic compounds
2000
Abstract Uranium tetrachloride, uranyle chloride, fluoride and also nitrate or acetate are very efficient homogeneous catalysts for the Friedel–Crafts acylation of aromatic compounds. With uranyle salts, the reaction, carried under dry air, is highly specific and the mono- or bisacylation products are obtained in high yield. Uranyle catalyst can be quantitatively recovered and reused and the organic products are obtained free of uranium.
Phosphonium-Boronate Amino Acid Derivatives as Fluoride Pincers for 18F-Labelling
2015
The synthesis of phosphonium-boronate amino acid derivatives was achieved by quaternization of o-boronatophenylphosphine with iodo-amino acid derivatives. Preliminary radiolabelling studies demonst...
Stereoselective glycosylation of Alcohols and Silyl Ethers Using Glycosyl Fluorides and Boron Trifluoride Etherate
1985
The stereoselective glycosylation of alcohols and their silyl ethers has been achieved using O-alkyl-, O-acyl-, and acetal-protected glycosyl fluorides of the pyranose and furanose series and boron trifluoride etherate in CH2Cl2.