الفهرس 
Introduction and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
Recently, biomimetic self assembly becomes one of the most interesting research directions in biomedicine field for its capabilities to produce implant components with the closest structural features to autogenous tissue. To date, there have been many studies dealing with this subject, but the results obtained are somewhat controversial. The present work was conducted to probe the feasibility of developing a well defined and reliable processing route for fabricating high performance biomimetically hydroxyapatite (HA) / polyvinyl alcohol (PVA) (70/30 by weight) porous nanocomposite scaffolds. Freeze- extraction concept was exploited as an adequate in situ making technique for the said scaffolds from mixture solution containing Ca2+, PO43- ions and PVA. The processing parameters investigated were concentration of mixture solution, type of extractive solvent, number of extractive solvent replacement and type of drying regime. Evaluation was carried out on basis of final product integrity as well as the resultant microstructure. The latter, was defined in terms of phase entity, as well as, dimensions, morphology, and distribution of grains, pores and interfaces using XRD, FTIR, TEM, density &porosity measurements and SEM. However, the most important comment to mention is that using conventional drying processes even at ambient humidity and room temperature during the preparative stage, all samples exhibited pore destruction and different types and degree of malformations that rendered them useless. Hence, an innovative drying system known as liquid desiccant drying method was additionally investigated. This technique proved to be greatly beneficial in eliminating or at least minimizing the drawbacks associated with the conventional drying. In brief, the results obtained showed that porous HA/PVA nanocopmposite, having an appropriate microstructure as guided-tissue regeneration scaffolds, can be produced via freeze-extraction in conjunction with liquid desiccant drying method under specified combination of optimized processing parameters.