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Herein, the aim was to study the state of the bone tissue adjacent to dental implants after the use of extracellular vesicles derived from multipotent stromal cells (MSC EVs) of bone marrow origin in the experiment. In compliance with the rules of asepsis and antiseptics under general intravenous anesthesia with propofol, the screw dental implants were installed in the proximal condyles of the tibia of outbred rabbits without and with preliminary introduction of 19.2 μg MSC EVs into each bone tissue defect. In 3, 7, and 10 days after the operation, the density of bone tissue adjacent to different parts of the implant using an X-ray unit with densitometer was measured. In addition, the histological examinations of the bone site with the hole from the removed device and the soft tissues from the surface of the proximal tibial condyle in the area of intra-bone implants were made. It was found out that 3 days after implantation with the use of MSC EVs, the bone density was statistically significantly higher by 47.2% than after the same implantation, but without the injection of MSC EVs. It is possible that as a result of the immunomodulatory action of MSC EVs, the activity of inflammation decreases, and, respectively, the degree of vasodilation in bones and leukocyte infiltration of the soft tissues are lower, in comparison with the surgery performed in the control group. The bone fragments formed during implantation are mainly consolidated with each other and with the regenerating bone. Day 10 demonstrated that all animals with the use of MSC EVs had almost complete fusion of the screw device with the bone tissue, whereas after the operation without the application of MSC EVs, the heterogeneous histologic pattern was observed: From almost complete osseointegration of the implant to the absolute absence of contact between the foreign body and the new formed bone. Therefore, the use of MSC EVs during the introduction of dental implants into the proximal condyle of the tibia of rabbits contributes to an increase of the bone tissue density near the device after 3 days and to the achievement of consistently successful osseointegration of implants 10 days after the surgery.

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Architectural and decorative concrete with the use of photoluminescent pigment accumulates solar energy, which is converted into light in the dark. The use of products with the glow effect provides an increase in safety in the dark. It is an additional mean of signaling on dangerous and poorly lit sections of roads, parking lots, bike paths. In addition, it allows to characterize this material as functional (the possibility of manufacturing a wide range of products), aesthetically expressive (highly decorative in the daytime), eco-friendly (the possibility of manufacturing with the use of man-made waste). Concrete with the use of photoluminescent pigments should not lose the properties of the glow, while the intensity of the glow should be maintained for a sufficiently long period. The criterion for choosing Portland cement for luminous architectural and decorative concretes is not only the aspect of decorative concrete, but also the effect of luminescence. An experiment is conducted to determine the degree of luminescence of photoluminescent pigment in concrete using white and grey Portland cement. A preliminary analysis of the literature and authors’ own research has shown that in order to enhance the effect of the photoluminescent pigment glow in concrete, the surface of the products must be sanded, which is also advisable for creating highly decorative surfaces of concrete products. The optimally selected materials and the method of surface treatment of the products ensure the decorative effect of architectural concrete even in the daytime.