An investigation of the technical aspects of producing sufficiently high strength porous biocompatible medical implants and tissue scaffolds from nitinol or pure titanium using selective laser sintering/melting (SLS/M) is presented. In particular, the necessary processing parameters and procedures for successful laser synthesis of functionally graded implants have been established. Physical and mechanical properties, microstructure, corrosion behavior of the synthesized structures, as well as shape memory in porous layered nitinol structures made using laser synthesis are reported. Comparative morphological and histological results of SLS of porous titanium and nitinol made implants are also presented. Investigations were carried out on primary cultures of dermal fibroblasts and mesenchymal stromal human cells. The possibility of cultivating bone marrow on the porous carrier-incubator made from NiTi and pure titaniumin vitro was determined. Sufficient understanding of the nature of laser synthesized titanium and nitinol structures was developed in order to determine their suitability for use as functional implants. This resulted in superior tissue to implant fixation and the development of minimally invasive surgical procedures.

Reconstruction of critical-sized bone defects remains a tremendous challenge for surgeons worldwide. Despite the variety of surgical techniques, current clinical strategies for bone defect repair demonstrate significant limitations and drawbacks, including donor-site morbidity, poor anatomical match, insufficient bone volume, bone graft resorption, and rejection. Bone tissue engineering (BTE) has emerged as a novel approach to guided bone tissue regeneration. BTE focuses on in vitro manipulations with seed cells, growth factors and bioactive scaffolds using bioreactors. The successful clinical translation of BTE requires overcoming a number of significant challenges. Currently, insufficient vascularization is the critical limitation for viability of the bone tissue-engineered construct. Furthermore, efficacy and safety of the scaffolds cell-seeding and exogenous growth factors administration are still controversial. The in vivo bioreactor principle (IVB) is an exceptionally promising concept for the in vivo bone tissue regeneration in a predictable patient-specific manner. This concept is based on the self-regenerative capacity of the human body, and combines flap prefabrication and axial vascularization strategies. Multiple experimental studies on in vivo BTE strategies presented in this review demonstrate the efficacy of this approach. Routine clinical application of the in vivo bioreactor principle is the future direction of BTE; however, it requires further investigation for overcoming some significant limitations.

This paper presents the results of Raman spectroscopy studies of 59 samples of hydroxyapatite produced from different types of bone tissue of a ram, cow, turkey, duck, and goose by isolation from solution during demineralization. The features of the Raman spectra of hydroxyapatite powders obtained from cancellous bone tissue with different degrees of demineralization and thermal processing are revealed. Coefficients are proposed that allow the estimation of the ratios of the decrease in the content of mineral components in the process of demineralization and the decomposition of organic substances under thermal action.

The results of experimental studies of the tissues of teeth with periodontitis, using the Raman spectroscopy method, are presented in this work. Spectral changes in the tissues of teeth with periodontitis were identified, and the results can be used for the correction of treatment of this disease in dental practice. Criteria for the noninvasive diagnosis of periodontitis, based on changes in tooth enamel spectral properties, were developed.

The musculoskeletal system, consisting of bones and cartilage of various types, muscles, ligaments, and tendons, is the basis of the human body. However, many pathological conditions caused by aging, lifestyle, disease, or trauma can damage its elements and lead to severe disfunction and significant worsening in the quality of life. Due to its structure and function, articular (hyaline) cartilage is the most susceptible to damage. Articular cartilage is a non-vascular tissue with constrained self-regeneration capabilities. Additionally, treatment methods, which have proven efficacy in stopping its degradation and promoting regeneration, still do not exist. Conservative treatment and physical therapy only relieve the symptoms associated with cartilage destruction, and traditional surgical interventions to repair defects or endoprosthetics are not without serious drawbacks. Thus, articular cartilage damage remains an urgent and actual problem requiring the development of new treatment approaches. The emergence of biofabrication technologies, including three-dimensional (3D) bioprinting, at the end of the 20th century, allowed reconstructive interventions to get a second wind. Three-dimensional bioprinting creates volume constraints that mimic the structure and function of natural tissue due to the combinations of biomaterials, living cells, and signal molecules to create. In our case—hyaline cartilage. Several approaches to articular cartilage biofabrication have been developed to date, including the promising technology of 3D bioprinting. This review represents the main achievements of such research direction and describes the technological processes and the necessary biomaterials, cell cultures, and signal molecules. Special attention is given to the basic materials for 3D bioprinting—hydrogels and bioinks, as well as the biopolymers underlying the indicated products.