The incorporation of various cations such as Zn (2+) into the structure of fluorapatite, Ca 5(PO 4) 3F, is governed by the effectiveness of the cations to substitute for Ca (2+) ions. In this work different concentrations of zinc were used to substitute for calcium. Microscopic characterization was done by observing the nanostructural variations induced by these zinc substitutions and by relati...

Equations have been derived and computations carried out for the demineralization rates of tooth enamel employing the “Fluorapatite” model. The model assumes that when hydroxyapatite is exposed to a low fluoride concentration, a layer of fluorapatite is formed around the apatite crystal and this fluorapatite is assumed to be the thermodynamic governing phase during dissolution. The demineralixa...

Through the complementary use of single-crystal X-ray diffraction and X-ray absorption spectroscopy, we present in this paper the first direct results on the site occupancy of thorium in the fluorapatite structure and the structural distortion created by its substitution. Structure refinements based on single-crystal X-ray diffraction data from synthetic Th-doped fluorapatite indicates that Th ...

Fluorapatite, fluorinated calcium phosphate, has been identified as a potential matrix for the entombment of the zirconium fluoride fission product waste stream from the proposed FLEX process. If the efficacy of fluorapatitebased waste-storage can be demonstrated, then new and potentially more-efficient options for handling and separating high-level wastes, based on fluoride-salt extraction, wi...

Fluorapatite, Ca10(PO4)6F2. is a widely spread form of calcium phosphate present particularly in biological material. Human hard tissues contain crystals structurally related to apatite. Fluoride can be found in various natural sources and is also used for its beneficial action in caries prevention. Fluorapatite belongs to the spatial group P6(3/m) (C(6h)2) and consists of 3 ions: F-, Ca2+, PO4...

Fluoride has a specific affinity for hydroxyapatite bone Ca10(PO4)6(OH)2. It lists the hydroxyl ions of hydroxyapatite crystals converting it into Fluor apatite, which entails a change of the physical characteristics of the crystals. Fluorapatite crystals are quick dimension "a" crystal, increased crystallinity and a reduced dissolve. Increased solubility of fluorapatite is the main cause of ch...

One approach to a fundamental study of the wear of a material is to investigate the frictional behavior and surface failure of a simplified system, such as single crystals, under conditions of single-pass sliding. Such an approach has been used to study the influence of sliding direction and environment on the surface failure of fluorapatite single crystals.1.2 A useful extension of this single...

OBJECTIVE The aim of this study was to evaluate the flexural strength of two porcelain materials (IPS d.SIGN and IPS e.max Ceram) exposed to erosive agents. MATERIAL AND METHODS One hundred and twenty bar-shaped specimens were made from each of fluorapatite-leucite porcelain (IPS d.SIGN) and fluorapatite porcelain (IPS e.max Ceram) and divided into 8 groups of 15 specimens each. Six groups we...

The paper discusses a possible new concept of the role of fluoride and its mechanism of action in caries prevention. In the past fluoride inhibition of caries was ascribed to reduced solubility due to incorporation of fluoride (F) into the enamel minerals (firmly bound fluoride or fluorapatite). Based on the new findings, it appears that fluoride, either released into or present in the fluid ph...