Porous hydroxyapatite was prepared in order to be used as a drug carrier and promote bone ingrowth. For this purpose, the microstructure should have interconnective pores and micro as well as macro porosity, for bone cell adhesion and bone ingrowth. The porous hydroxyapatite prepared by the burn-out method exhibits all these features. For measuring porosity, SEM analysis, mercury intrusion poro...

In this work, the sintering and grain growth of hydroxyapatite green bodies are analyzed in order to identify the optimum heat treatments for the preparation of porous hydroxyapatite scaffolds. Sintering in air at temperatures ranging between 1100 and 1200 °C yields dense materials with narrow grain-size distributions. The scaffolds are formed by the infiltration of polymer foams with hydroxyap...

We have used the pH-induced self-assembly of a peptide-amphiphile to make a nanostructured fibrous scaffold reminiscent of extracellular matrix. The design of this peptide-amphiphile allows the nanofibers to be reversibly cross-linked to enhance or decrease their structural integrity. After cross-linking, the fibers are able to direct mineralization of hydroxyapatite to form a composite materia...

We presented a case in which massive hydroxyapatite accumulation was observed around the artificial hip joint. A 66-year-old female showed a massive accumulation of fluid in and around the hip joint, and milk-like aspirate was obtained. Her aspirate culture was negative, and sediment analysis by X-ray diffraction showed that its component was hydroxyapatite. Since pain was mild, the patient was...

Hydroxyapatite is the main mineral that makes up bones and teeth so it has a level of similarity with parts can be used as an alternative bone substitute material. As material for substitution, hydroxyapatite fairly high economic value still dominated by imports from foreign countries. In effort to reduce hydroxyapatite, research was carried out on green mussel shells source calcium synthesis h...

The purpose of this study is to analyze the exposure specific exchange rate sectors due changes in regimes. To evaluate and consequence policy change, two models were used. data was from Malaysian listed firms' stock returns foreign rates. secondary 128 firms chosen using Bloomberg database Bursa Malaysia. firm’s price rates collected January 1990 July 2010. 20 years specifically obtain regime ...

Excess urea fertilizer application to the agricultural fields causes severe environmental deterioration. Researchers actively seek safer alternatives, such as nanoparticles with unique properties, reduce chemical inputs without compromising output. In present study, three variants─hydroxyapatite–urea, magnesium-doped hydroxyapatite–urea, and zinc-doped hydroxyapatite–urea nanohybrids─have been ...

An opaque, white chitosan/ Hydroxyapatite nanocomposite was prepared by a simple blend method. Morphology, pore size and dispersion of nano-hydroxyapatite in chitosan matrix were visualized using SEM images. The FTIR with EDX analysis confirmed the bony apatite layer formed on outside composite. Porosity measurements water uptake studies evaluated which revealed maximum porosity 80% to 92% chit...

purpose: to present our experience with cyanoacrylate tissue adhesive in eyes with exposed hydroxyapatite orbital implants. methods: cyanoacrylate tissue adhesive was used in 3 patients with hydroxyapatite orbital implant exposure defects. results: cyanoacrylate glue was applied on the defective area of 3 patients presenting with small exposure (<4mm). the patients were followed for 33 months (...

In 33 dogs we implanted femoral stems made either of carbon composite, some coated with hydroxyapatite, or of titanium alloy with a porous coating. Osseointegration was greater in the hydroxyapatite-coated than in the un-coated stems (p less than 0.001). Push-out tests, at an average of 7.2 months after implantation, showed a six-fold increase in interface shear strength and a twelve-fold incre...