The structure and physicochemical mechanisms of interaction of bone tissue with titanium implants in tuberculous osteitis have been studied by scanning electron microscopy, X-ray phase analysis, IR spectroscopy and thermal analysis methods. It has been found that the physiological regeneration of bone tissue is accompanied by growth of organic components, embrittlement of the mineral phase of the bone matrix, and its fine disintegration during the treatment of tuberculosis osteitis. The presence of titanium implants during a physiologically normal state contributes to the activation of apatite phase synthesis in the regenerating bone. The main mechanism of implantation osteogenesis in tuberculous osteitis is the formation of the inorganic phase of hydroxyapatite mainly in the areas of destruction of the titanium alloy.

The physicochemical properties and structure of the bone matrix are studied in a case of simulated tuberculous osteitis without treatment and after a full course of specific antibacterial therapy. Using X-ray diffraction, infrared spectroscopy, thermal analysis, and scanning electron microscopy, we revealed that tuberculous osteitis causes fine disintegration of the bone matrix due to an increase in nonstoichiometric hydroxyapatite, formation of amorphous calcium phosphates, and a decrease of the organic phase, which is accompanied by embrittlement of the bone matrix. Excessive growth of carbonate-hydroxyapatite crystals of a mixed AB substitution type leads to excessive osteogenesis, accompanied by the uncontrolled growth of bone trabeculae. The presence of “liming” regions in the crystal lattice of hydroxyapatite increases the “binding” properties of the bone matrix in which mycobacteria are immobilized and removed in the composition of detritus.

AbstractThe physicochemical properties and structure of the bone matrix are studied in a case of simulated tuberculous osteitis without treatment and after a full course of specific antibacterial therapy. Using X-ray diffraction, infrared spectroscopy, thermal analysis, and scanning electron microscopy, we revealed that tuberculous osteitis causes fine disintegration of the bone matrix due to an increase in nonstoichiometric hydroxyapatite, formation of amorphous calcium phosphates, and a decrease of the organic phase, which is accompanied by embrittlement of the bone matrix. Excessive growth of carbonate-hydroxyapatite crystals of a mixed AB substitution type leads to excessive osteogenesis, accompanied by the uncontrolled growth of bone trabeculae. The presence of “liming” regions in the crystal lattice of hydroxyapatite increases the “binding” properties of the bone matrix in which mycobacteria are immobilized and removed in the composition of detritus.

Bovine pericardium samples modified with ethylene glycol diglycidyl ether, designed for surgical correction of congenital heart defects and large blood vessels, were studied by scanning electron microscopy, X-ray diffraction, IR spectroscopy, and differential thermal analysis. It was found that the initial samples of pericardium, before implantation, contain sites of disorganization of the collagen matrix, fragile fracture of collagen fibrils and destruction of the interstitial membranes promoting the penetration of immunocytes into the deep layers of the pericardium. Ossifying calcification with amorphized hydroxyapatite deposition and bone tissue formation as well as multiple erosions and hypertrophic proliferation in the endothelial membrane were detected in the implantation pericardium samples.

Mesoporous calcium phosphate granules ranging in mesopore size from 11 to 19 nm have been prepared using cryogenic processing (–18°C) of gels and extrusion of calcium phosphate paste. The granules based on acid calcium phosphates have a relatively small specific surface area (45 m 2 /g) in comparison with the neutral and basic calcium phosphates (84–155 m 2 /g). Preclinical in vivo trials on rats show that the presence of calcium phosphate granules in a bone defect considerably accelerates reparative osteogenesis in comparison with a control group of animals.

The aim of the research is to study modern data on results of medical application of diamond-like coatings. Material and methods. We have reviewed scientific English and Russian-language articles available in the Medline database and on the Internet meeting enquiries «diamond-like coating», «application of diamond-like coatings», «biocompatibility of diamond-like coatings». In the course of the search we looked through about 800 sources of patent and scientific medical information and selected 17 units of patent information and 44 units of scientific medical information for further study. Results. We systematized modern data on the results of the experimental and clinical application of diamond-like coatings, their unique properties. Together with description of failed cases of the application of implants with diamond-like coatings, there are a large number of experiments and cases with positive results in clinical practice. Conclusion. A large number of both preclinical and clinical studies on the application of diamond-like coated implants are needed.

The aim of the research is to study modern data on results of medical application of diamond-like coatings. Material and methods. We have reviewed scientific English and Russian-language articles available in the Medline database and on the Internet meeting enquiries «diamond-like coating», «application of diamond-like coatings», «biocompatibility of diamond-like coatings». In the course of the search we looked through about 800 sources of patent and scientific medical information and selected 17 units of patent information and 44 units of scientific medical information for further study. Results. We systematized modern data on the results of the experimental and clinical application of diamond-like coatings, their unique properties. Together with description of failed cases of the application of implants with diamond-like coatings, there are a large number of experiments and cases with positive results in clinical practice. Conclusion. A large number of both preclinical and clinical studies on the application of diamond-like coated implants are needed.

The technique of combined DC metal arc and carbon pulsed arc was used to deposit thin solid films containing up to 6.5 at.% of silver. The microstructure and antibacterial properties of silver-doped diamondlike carbon (DLC) films have been investigated. Silver nanoparticle of flat disk shape located inside of an amorphous carbon matrix revealed excellent antibacterial properties concerning Staphylococcus aureus bacteria. Titanium substrates with DLC films doped with silver have an inhibiting effect on growth of some tumors, in particular, on rat neoplastic C6 glioma. This result is new and opens further possibility for application of DLC:Ag composite in medicine. (C) 2009 Published by Elsevier B.V.