The Morphological Characteristics of Bone Tissue Regeneration in the Application of Bone Grafting Auto-Mixture

Objective: to study the morphological and morphometric features of bone tissue regeneration in the application of the native transplantation automixture during bone defects replacement in an experiment. Material and methods. Male Wistar rats weighing 180-200 g. and aged 6-7 months were used. The bone defect was modeled using a 1.2 mm diameter cutter (experimental group). A similar defect of the middle third of the right tibia without filling the defect with bone tissue was formed in the animals of the control group. The animals were taken out of the experiment on the 3rd, 7th, 14th, and 30th days of the experiment (6 animals per each observation period). Histological sections 4-5 µm thick were stained with hematoxylin and eosin. The areas of necrosis, granulation tissue, bone trabecules (mm2) were determined. Results. The laboratory animals in which the bone mixture had been transplanted revealed the growth of the area occupied by granulation tissue from the 3rd to 7th day of the experiment, and later its area had decreased by the 30th day compared to the control group, which was associated with faster transformation of granulation tissue into bone trabecules and formation of the foci of cerebrospinal hematopoiesis. On the 7th day of the experiment, the area of necrosis in the control group significantly exceeded the indicators of the experimental group (р ˂ 0.001). On the 14th day of the experiment necrosis in the animals of the experimental group was absent, while in the control one there were still some necrosis foci (0.541 ± 0.014 mm2). Starting from the 7th of the experiment, immature bone tissue began to form within the area of the bone tissue defect. At the same time, its area in the animals of the experimental group was statistically significantly larger on the 7th, 14th and 30th days in comparison with the control group during all observation terms (р ˂ 0.001). Conclusion. The study has showed a higher rate of bone tissue formation in the bone defects in the experimental animals after autotransplantation of the bone mixture. The obtained results of bone autoplasty can be a theoretical basis for the development of the methods of the treatment of bone defects of any origin.