Evaluation of the effectiveness of osteoregeneration using rhBMP-2 and bone allograft on a model of femoral defect in rabbits

Aim . To carry out a histological and histomorphometric assessment of bone tissue regeneration processes using a bone allograph prepared according to the Marburg bone bank system in combination with rhBMP-2 on a rabbit femoral defect model. Materials and methods. In this study, 2 groups were formed, each with 24 subjects (rabbits), who had a defect with a diameter of 5 mm in the distal metaphysis of the femur. In group 1, the defect was filled with bone allograft in combination with rhBMP-2. In group 2, the defect was filled with bone allograft without additional drugs. Further, histological and statistical processing of the obtained data was carried out. Results . On day 14, in the AG+rhBMP-2 group, newly formed bone tissue amounted to 34.75±5.67% of the total area of the cortical plate defect. On day 30, in the AG+rhBMP-2 group, the closure of the cortical plate defect was 79.12±14.32%, the newly formed bone tissue covered 80.75% of the length and 71.37% of the thickness of the cortical plate. On day 60 in the AG+rhBMP-2 group, newly formed bone tissue covered the total area of the cortical plate defect by 64.50±27.73%, length by 62%, and thickness by 65.25%. Discussion . The data obtained indicate an acceleration of osteoregeneration in the early stages of bone plate restoration in the AG+rhBMP-2 group, however, the results obtained by 60 days were extremely heterogeneous, indicating the dysenergic effect of rhBMP-2 on mesenchymal progenitor cells and the associated excessive resorptive effect of rhBMP-2 in some cases. Conclusion . According to the results of this study, it can be seen that the use of bone allograft in combination with rhBMP-2 at the late stages of bone regeneration leads to unsatisfactory results, which manifests itself in the form of high heterogeneity of the data obtained, among which, in a significant part of cases, there is not sufficient closure of the defect with newly formed bone tissue.