Biomedical subjects

F N Oktar

Publications and source records attributed to F N Oktar.

3 recordsLinked to original sources

PubMed2006

Bond-coating in plasma-sprayed calcium-phosphate coatings.

The influence of bond-coating on the mechanical properties of plasma-spray coatings of hydroxyatite on Ti was investigated. Plasma-spray powder was produced from human teeth enamel and dentine. Before processing the main apatite coating, a very thin layer of Al2O3/TiO2 was applied on super clean and roughened, by Al2O3 blasting, Ti surface as bond-coating. The experimental results showed that bond-coating caused significant increase of the mechanical properties of the coating layer: In the case of the enamel powder from 6.66 MPa of the simple coating to 9.71 MPa for the bond-coating and in the case of the dentine powder from 6.27 MPa to 7.84 MPa, respectively. Both tooth derived powders feature high thermal stability likely due to their relatively high content of fluorine. Therefore, F-rich apatites, such those investigated in this study, emerge themselves as superior candidate materials for calcium phosphate coatings of producing medical devices. The methods of apatite powder production and shaping optimization of powder particles are both key factors of a successful coating. The methods used in this study can be adopted as handy, inexpensive and reliable ways to produce high quality of powders for plasma spray purposes.

Apatites↗

PubMed2005

Scaffolds for bone restoration from cuttlefish.

Scaffolds of pure hydroxyapatite suitable for either direct clinical use or tissue-engineering applications were successfully produced via hydrothermal transformation of aragonite, obtained from fresh cuttlefish bones, at 200 degrees C followed by sintering. Beyond low production cost, worldwide availability and natural-biological origin of raw materials, the produced scaffolds have ideal pore size and interconnectivity features suitable for supporting biological activities, such as bone tissue growth and vascularization. Bioactivity in vitro tests were excellent: (a) rapid and pronounced formation of hydroxyapatite occurred when the scaffolds were immersed in simulated body fluid (SBF), and (b) outstanding proliferation of osteoblasts was registered. The produced scaffolds can be machined and shaped very easily at any stage of processing. Therefore, these ceramic scaffolds can satisfy both bioactivity demands and the requirements for shaping of tailor-made individualized implants, especially for randomly damaged bones.

Animals↗

PubMed1999

Characterization of processed tooth hydroxyapatite for potential biomedical implant applications.

In this study hydroxyapatite (HA) (100-150 microns) derived from freshly-extracted human teeth in laboratory conditions was investigated. Scanning electron microscope (SEM), energy dispersive x-ray spectroscopy (EDXS), wet chemical, ion chromatographic peak method (ICP), atomic absorption, x-ray diffraction and infra-red (IR) were performed separately for HA obtained from dentine and enamel. This naturally derived HA did not differ from synthetic ones. Its production was simple when compared with other methods. Processed tooth HA could safely be used in animal subjects prior to human studies as a graft material after biocompatibility studies fully conducted.

Animals↗