Detonation-produced hydroxyapatite coatings were studied by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Raman spectroscopy, and electron paramagnetic resonance (EPR) spectroscopy. The source material for detonation spraying was a B-type carbonated hydroxyapatite powder. The coatings consisted of tetracalcium phosphate and apatite. The ratio depended slightly on the degre...

INTRODUCTION Fractures of the neck of the femoral component have been reported in uncemented total hip replacements, however, to our knowledge, no fractures of the neck of a cementless forged titanium alloy femoral stem coated in the proximal third with hydroxy-apatite have been reported in the medical literature. CASE PRESENTATION This case report describes a fracture of the neck of a cement...

Six subjects (three female, three male; age range 38-85 years) with adult onset hypophosphatasia are described. Three presented atypically with calcific periarthritis (due to apatite) in the absence of osteopenia; two had classical presentation with osteopenic fracture; and one was the asymptomatic father of one of the patients with calcific periarthritis. All three subjects over age 70 had iso...

Strontium can be deposited in bone apatite either by the replacement of surface adsorbed calcium, or by substitution for intracrystalline calcium (1-3). It has also been reported that both of these processes favor the deposition of calcium to that of strontium (3). This report is concerned with the comparative incorporation of calcium and strontium in synthetic apatites. We shall present eviden...

Dissolution rate studies were conducted with hydroxyapatite and enamel in the presence of adsorbed surfactants. In general, the ability of the surfactant to retard the dissolution rate was directly related to its ability to adsorb onto apatite. Cetylpyridinium chloride adsorbed poorly onto apatite, and its influence on the dissolution rate was marginal. The long-chain protonated amines were muc...

Gamma-methacryloxypropyltrimethoxysilane (gamma-MPS) was grafted to high-density polyethylene, polyamide and silicone rubber substrates by the emulsion polymerization procedure in order to provide these organic polymers with in vitro apatite-forming ability. The contact angles towards distilled water of the gamma-MPS-grafted specimens were lower than those of the original organic polymer specim...

More than 200 specimens from different occurrences of the Rogaland igneous complex and surrounding granulite facies metamorphic rocks (S. W. Norway) have been analysed by a direct non-destructive proton induced gamma-ray emission (PIGE) technique. The fluorine contents vary from < 25 ppm to 3500 ppm. There is a good correlation between the concentration of fluorine and that of phosphorus for ig...

Atomic force microscopy, infrared spectroscopy and NMR studied morphological and physicochemical properties of calcium hydroxyapatite powders produced by changing the temperature parameters of synthesis. Features of morphology formation of calcium hydroxyapatite nanoparticles with an annealing temperature within 200°C to 1,100°C were determined. It is shown that the particle size of the apatite...

Etched tracks of apatite and zircon are both widely used for the determination of the thermal history of Earth’s crust. The present understanding of the annealing process is largely limited to mathematical fits to data for etched track-lengths as a function of temperature and time. Details of the annealing of unetched, latent tracks at the atomic scale have remained elusive, as the original tra...