Fabrication and characterization of porous hydroxyapatite and biphasic calcium phosphate ceramic as bone substitutes

Koc, N
Timucin, M
Korkusuz, Feza
In the present study, the calcium phosphate powders (HAP, HAP-TCP) were produced by a precipitation technique involving the use of aqueous solutions of calcium nitrate and diammonium hydrogen phosphate. Preforms of calcium phosphate ceramics were produced by using a modified slip casting technique. Porosity in the cast and in the sintered ceramic was obtained through custom made PMMA beads similar to200-300 mum size. The green ceramic samples were prepared by suspending the apatite powder and PMMA beads in an aqueous medium stabilized with an acrylic deflocculant. Porous ceramics were obtained by sintering the polymer-free preforms for 2 hours at 1000degreesC to 1200degreesC. Pore size and pore size distribution as revealed by SEM analyses were appropriate for repair of cortical defects.


Synthesis of biomimetic Ca-hydroxyapatite powders at 37 degrees C in synthetic body fluids
Tas, AC (2000-07-01)
An important inorganic phase for synthetic bone applications, calcium hydroxyapatite (HA, Ca-10(PO4)(6)(OH)(2)), was prepared as a nano-sized (similar to 50 nm), homogeneous and high-purity ceramic powder from calcium nitrate tetrahydrate and diammonium hydrogen phosphate salts dissolved in modified synthetic body fluid (SBF) solutions at 37 degrees C and pH of 7.4 using a novel chemical precipitation technique. The synthesized precursors were found to easily reach a phase purity >99% after 6 h of calcinati...
Preparation of porous Ca-10(PO4)(6)(OH)(2) and beta-Ca-3(PO4)(2) bioceramics
Engin, NO; Tas, AC (2000-07-01)
Submicrometer-sized, pure calcium hydroxyapatite (HA, (Ca-10(PO4)(6)(OH)(2))) and eta-tricalcium phosphate (beta-TCP, Ca-3(PO4)(2)) bioceramic powders, that have been synthesized via chemical precipitation techniques, were used in the preparation of aqueous slurries that contained methyl cellulose to manufacture porous (70%-95% porosity) HA or beta-TCP ceramics. The pore sizes in HA bioceramics of this study were 200-400 mu m, whereas those of beta-TCP bioceramics were 100-300 mu m. The pore morphology and ...
Synthesis and characterization of nanosized calcium phosphates by flame spray pyrolysis, and their effect on osteogenic differentiation of stem cells
Ataol, Sibel; Tezcaner, Ayşen; Duygulu, Ozgur; Keskin, Dilek; Machin, Nesrin E. (2015-02-14)
The present study evaluates the synthesis of biocompatible osteoconductive and osteoinductive nano calcium phosphate (CaP) particles by industrially applied, aerosol-derived flame spray pyrolysis method for biomedical field. Calcium phosphate nanoparticles were produced in a range of calcium-to-phosphorus ratio, (1.20-2.19) in order to analyze the morphology and crystallinity changes, and to test the bioactivity of particles. The characterization results confirmed that nanometer-sized, spherical calcium pho...
Production and characterization of activated carbon from hazelnut shell and hazelnut husk
Çuhadar, Çiğdem; Yücel, Hayrettin; Department of Chemical Engineering (2005)
In this study, the pore structures and surface areas of activated carbons produced from hazelnut shell and hazelnut husk by chemical activation technique using phosphoric acid (H3PO4), at relatively low temperatures (300, 400 and 500oC), were investigated. Raw materials were impregnated with different H3PO4 solutions of 30%, 40%, 50% and 60% by weight. To produce activated carbon, acid impregnated samples were heated; at a heating rate of 20 oC/min to the final carbonization temperature and held at that tem...
Preparation, modification, and characterization of acrylic cements
Basgorenay, B; Ulubayram, K; Serbetci, K; Onurhan, E; Hasırcı, Nesrin (2006-03-15)
Acrylic cements with different compositions were prepared by mixing the solid part (composed of poly(methyl methacrylate), PMMA, and benzoyl peroxide, BPO) and the liquid part (composed of methyl methacrylate, MMA, and N,N-dimethyl-p-toluidine, DMPT), modified by addition of hydroxyapatite (HA) and ammonium nitrate (AN) and characterized by measuring thermal and mechanical properties. Three sets of samples were prepared. For B-group, the total amount of solid including HA was constant but the PMMA to HA rat...
Citation Formats
N. Koc, M. Timucin, and F. Korkusuz, “Fabrication and characterization of porous hydroxyapatite and biphasic calcium phosphate ceramic as bone substitutes,” BIOCERAMICS 16, pp. 949–952, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51497.