Sergei Gennadievich Anikeev

TiNi-based alloys are widely utilized in various engineering and medical applications. This study presents a newly developed and optimized technology for producing TiNi wires with a diameter of 40 μm utilizing a combined mechano-chemical treatment and drawing process. The resulting thin wires were tested and characterized using multiple methods to determine their structural, phase, and mechanical properties. The structure of the TiNi wires, designed for use as textile implants in reconstructive medicine, features a TiNi metal matrix (B2 and B19′ phases) at the core and a surface oxide layer. A key structural characteristic of these wires is the presence of fine nanograins averaging 15–17 nm in size. No texturizing of the metallic material was observed during repeated plastic deformations throughout the drawing process. The applied mechano-chemical treatment aimed to modify the structure of the wires’ surface oxide layer. Specifically, reducing the thickness and roughness of this layer decreased the friction coefficient of the alloy during drawing, thus significantly reducing the number of breaks during production. At the same time, the cryogenic treatment of the final product was found to stabilize the martensitic phase B19′, which reduces the Young’s modulus by 10 GPa. Consequently, this newly developed methodology enhances the material’s quality and reduces labor costs during production.

Purpose of the study: to conduct a comparative assessment of the formation of the sphincter mechanism during colostomy using titanium nickelide-based implants in an experiment.Material and methods. The experimental study was conducted on 45 sexually mature male rats Wistar with an average body weight of (531.3 ± 13.4) g. The animals were randomized into three equal groups of 15 animals each. In the 1st experimental group, a cylindrical spiral made of titanium nickelide with invagination of the serosalmuscular layer of the colon was used to create a colostomy. In the 2nd experimental group, a similar spiral was used, but without invagination of the serous-muscular layer. The control group underwent the standard procedure of single-barrel colostomy formation. Animals were removed from the experiment on the 7th, 30th and 60th days after the operation, 5 animals at each stage. Histologic examination of the area of the formed colostomy with constipation apparatus was performed.Results. The use of cylindrical spiral implants from titanium nickelide in colostomy formation (both with and without invagination of the serosal-muscular layer of the colon) had no significant effect on the dynamics of body weight of experimental animals compared to the classical method. Colostomy formation without invagination of the serous-muscular layer did not lead to an increase in the incidence of postoperative complications in comparison with the traditional method. However, invagination of the serous-muscular layer was accompanied by an increased incidence of complications in the postoperative period.Conclusion. The complex analysis of experimental data, including the assessment of survival rate, body weight dynamics, incidence of postoperative complications, morphological changes, the course of regenerative processes and stoma functionality, allows us to recommend as a promising method of colostomy the use of a cylindrical spiral made of titanium nickelide without invagination of the serous-muscular layer of the intestine.

The study focuses on a novel porous TiNi-based material for ophthalmic orbital implants which was produced by self-propagating high-temperature synthesis (SHS) and, after proper surface modification, possesses a specific microstructure of its surface pores, which makes it attractive for biomedical use in implants. After preparation via SHS, the obtained porous TiNi material was etched in acidic environment, to get rid of its surface Ti2Ni secondary-phase particles. This was found to improve the material’s surface morphology, adding micro-roughness to its macro-rough pores. As a result, cell growth tests conducted on the material demonstrated improved cell adhesion and growth kinetics on such a porous material with improved roughness. Finally, the material was tested in vivo as an ophthalmic orbital implant, demonstrating good biocompatibility, good degree of biointegration with surrounding eyeball tissues, and no signs of rejection after as long as 180 days. Thus, the novel porous TiNi-based material shows promise for its use in ophthalmic implantology, for instanse for manufacturing musculoskeletal stumps of the eyeball after evisceration, as it is biocompatible, has a high tissue-implant integration potential and demonstrates reduced risks of exposure and rejection of the implant.