I.A. Talashova, T.A. Silantieva

The development of implantation materials that are close to bone tissue in their composition and possess the features of biocompatibility and osteointegration is a current task for the specialists in different fields of knowledge. Our study was aimed at the assessment of the effect of the composition of original calcium phosphate implantation materials (CPM) on their biodegradation and biointegration in the area of created bone defect. The tested implantation materials were calcium phosphate compounds (CPC) that were obtained from the mature cattle long bone diaphysis using various technologies of isolation. The qualitative composition of CPC was studied with infrared spectroscopy. In order to determine the elements of the studied CPC, massive calcium concentrations, phosphorus, magnesium, sulphur, and chlorine the method of electron probe microanalysis (EPMA) was used. The morphology and mineral composition of the developed materials were studied with the methods of light and scanning electron microscopy (SEM). CPM tests were performed on 20 adult dogs. Cone-shaped blind-ended defects in the humeral and tibial diaphyses were created through 5 to 7 mm conical blind-ended holes made with a drill. After analyzing the findings of IR spectrometry, EPMA and SEM, as well as descriptive and quantitative histological findings it was established that the composition of CPC depends on the technology of its isolation from the cattle bone tissue. CPC1 that was obtained with the aids of sparing technology and that had the substances of protein nature showed mild biodegradation properties and high biointegration when embedded into the defect area. The procession of CPCII with carbamide solution as an additional phase that cleared the material of precipitated bone proteins resulted in prolongation of the biodegradation stage and in reduction of the material integration degree into the bone tissue. The application of 6 n HCl solution for demineralization of cattle bone tissue and the use of calcium hydrochloride for CPC precipitation resulted in considerable change of the material composition and its structural properties. Therefore, it featured high rate of biodegradation combined with sharp impairment of osteoinductive and osteoconductive properties.