PROCESS FOR OBTAINING A PRODUCT FOR THE RECONSTRUCTION OF BONE DEFECTS, BASED ON HYDROXIAPATITE AND BIOGENIC BIPHASSIC CALCIUM PHOSPHATE

The invention relates to a process for the production of a product for the reconstruction of bone defects, based on hydroxyapatite and biogenic biphasic calcium phosphate, with a controlled ratio between hydroxyapatite / tricalcium phosphate, including a preliminary phase for obtaining hydroxyapatite by thermal dissociation of carbonate from calcium in the form of dolomitic marble and sea shells, hydration of calcium oxide, treatment of calcium hydroxide solution with phosphoric acid of 85% concentration in the amount of 100-130% x calculated stoichiometric amount, drying at 120 ° C and grinding, powders obtained being mixed with sectioned and braided / twisted hemp fibers in the form of a bundle and then soaked in aqueous starch solution obtained by mixing volumetric parts of starch / distilled water in a thermostated bath at 70 – 80 ° C, the resulting mixture being compacted by pressing cold isostatic in molds with Φ 10 – 50 mm at compressive forces between 10 – 25 MPa, the product is nal being obtained by sintering in an electric oven at 900 – 1300 ° C for 1 – 12 hours, in an air atmosphere. The porosity of the product, in the form of interconnected channels, results from the complete combustion of the introduced organic materials, the dimensional reduction of the channels being directly proportional to that of the cylindrical samples, in the range 20-35%, and the modulation of mechanical characteristics obtained by changing the temperature and of the sintering holding time.