Medical article медицинская статья

Currently, there is a growing scientific interest in the condition of the soft tissues surrounding dental implants and their impact on the long-term prognosis of implant treatment. Known risk factors for the development of peri-implantitis include deficiency or complete absence of attached keratinized gum in the implant area. Various grafts are used to form a peri-implant “buffer” zone. When planning orthopedic structures on implants, the participation of a doctor – a dental surgeon and an orthopedist – is important. However, there is still no consensus on the required volume of keratinized gum around dental implants. According to numerous authors, it has been shown that dental implants installed in mobile gums often lose epithelial attachment, which subsequently leads to the development of peri-implantitis. Other researchers believe that the absence. There is an opinion that since dental implants with a rough surface are currently used in the vast majority of cases, a thickness of keratinized gum of no more than 2.0 mm is sufficient to form a peri-implant “buffer” zone. Moreover, in its distal sections the density of microvessels is greatest, in the middle sections it is the smallest, and in the frontal sections it occupies an intermediate position. The paper provides an analysis of various methods of mucogingival surgery in the area of dental implants using an allogeneic graft from the fascia lata of the thigh of the Alloplant series.

Introduction. The question of the possibility of recovery of postischemic myocardium remains relevant.Aim. The aim of the study was to study the effect of dispersed decellularized allogeneic extracellular matrix (allogeneic biomaterial, DAB) on the developed fibrous degeneration of the myocardium, as well as to reveal the possible mechanisms of cellular regeneration.Materials and methods. The muscular wall of the heart of rats was subjected to cryodestruction. After 45 days, the rats of the main group were intramyocardially injected with a suspension of allogeneic biomaterialinto the area of the affected myocardium, and the rats of the control group were injected with saline.Results and discussions. In the experimental group, there was a regression of the formed fibrous connective tissue, chemoattraction of progenitor cells, their differentiation and integration into the myocardium. The thickness of the muscular part of the wall of the left ventricle was three orders of magnitude higher than in the control group.Conclusion. Analysis of the results of the study indicates that the heart in adult mammals has a powerful regenerative reserve. It is likely that, based on the use of DAB, a protocol can be developed that allows the restoration of the heart muscle even in conditions of already developed fibrous degeneration.

The work conducted a study of the phenotype of the gum after dental implantation surgery using testiqular albuginea allografts in comparison with dental implantation with apical displacement of the split mucous flap without the use of transimplants. The growth of keratized gum was assessed immediately after surgery and 6 months after surgical treatment. Morphological studies of biopsy tissue samples from the implant projection zone were conducted. The results of microscopic studies and photographing of samples are presented. Based on the obtained results, it was concluded that testicular albuginea allografts are completely replaced by a structurally complete connective tissue regenerate, but at the transplantation site, a phenotype of “thin” gum (thickness 1 mm or less) is formed, which, most likely, will not be able to provide adequate protection of the underlying tissues, which will contribute to plaque retention and subsequent inflammation.

Camels have developed unique adaptive mechanisms, one of which is the active accumulation of lipids. This metabolic feature has a direct influence on the liver ultrastructure. Its analysis reveals how exactly the hepatocytes have evolved to effectively store fat and neutralize toxins, which is crucial for survival in the desert. Considering the latter, the aim of this research is to establish the features of the microstructural organization of the liver of the Bactrian camel (Camelus bactrianus). This study was conducted using 15 liver tissue fragments from 5 healthy Bacterian camels (3 pieces from each animal) via biopsy. The sections were examined using a JEM-1011 electron microscope at magnifications of 2500–8000. Electron microscopic analysis of hepatocytes revealed a significantly larger hepatocyte diameter (25–30 µm), suggesting an adaptation for metabolites and water storage. Hepatocytes exhibited fewer, medium-sized (0.5–2 µm) lipid droplets, present in only 12–15% of cells. A high density of specialized Kupffer (15–20 cells per 10,000 µm²) and activated Ito cells was observed, indicating enhanced detoxification and immune functions. These specific ultrastructural features provide a model for studying metabolic resistance and inform veterinary diagnostics and husbandry practices for this species.

PURPOSE. Improving the results of the operation and achieving its reliability in secondary glaucoma, including refractory glaucoma, can be done using a non-biodestructible allograft drainage with spongy structure fabricated by Alloplant^® technology.METHODS. Experimental and morphological studies conducted in the Russian Eye and Plastic Surgery Center showed that the allogeneic spongy biomaterial used for anti-glaucoma sponge drainage surgery is gradually replaced by loose tissue with a porous structure, similar to trabecular, forming a new drainage system. During the operation, the proximal part of the drainage is inserted through the excised drainage zone in the anterior chamber angle (ACA). The distal part is tucked into the suprachoroidal space through a linear incision in the scleral bed.RESULTS. The newly created topography of the ACA after sponge drainage operation with the use of allogeneic biomaterial features not only the expansion of the ACA profile, but also the replacement of the excised part of the drainage zone with biomaterial after sinus trabeculectomy (STE) and elimination of retention of the intraocular fluid (IOF) outflow. Ultrasound biomicroscopy (UBM) performed at various times after antiglaucoma surgery showed that the microtubule system preserved. Optical coherence tomography (OCT) of the ACA demonstrates the location of the drainage in the long-term follow-up.CONCLUSION. Antiglaucoma operation with the use of allogeneic biomaterial with spongy structure promotes the formation of trabecula-like tissue in the ACA, eliminates retention of IOF outflow, and reduces the risk of scleroscleral and sclero-conjunctival adhesions.