Аннотация
BACKGROUNDThe development of bone substitutes that combine mechanical stability with high osteoregenerative potential remains a challenge in orthopedics.Previous studies confirmed the efficacy of a composite based on nanofibrillated cellulose (NFC) and bone xenograft in rabbit models.We reasoned that blending these components could yield superior outcomes given their individual properties, and we identified a suitable binding agent to achieve this.We hypothesize that a uniformly mixed composite provides superior integration and stability compared to standard bone grafting methods. AIMTo evaluate the osteoregenerative potential, remodeling patterns, and migration resistance of NFC/xenograft/Butvar-phenolic (BP)-adhesive composite implanted in a rat femoral defect model. METHODSNinety-nine rats were randomly divided into three equal groups, and a defect 2 mm in diameter and 1 mm in depth was created in the mid-diaphysis of the femur.In the first group (control), intervention was performed without defect filling.In the second group (xenograft), the defect was filled with a xenograft prepared according to the Marburgbone bank system.In the third group (composite), a homogeneous mixture was prepared by pre-mixing the components, and this material was implanted into the defect cavity.Eleven animals from each group were withdrawn from the experiment on days 30, 60, and 90, and histological, histochemical, and histomorphometric examinations of the femur at the surgical site were performed to assess bone defect regeneration, remodeling, and composite migration.In addition, an infected wound model was established.In two groups, xenograft and composite, of 11 animals each, the defect cavity 4 / 41 was inoculated with Staphylococcus aureus prior to graft filling.The animals were withdrawn from the experiment on day 30, and histological examination was performed to assess inflammation. RESULTSThe use of a composite based on NFC, a xenograft, and BP adhesive, as compared with the xenograft alone and empty defect, improved cortical bone regeneration on days 30 and 60 relative to the control group and xenograft group (P = 0.001).On day 30, the composite underwent active remodeling in both the central and peripheral zones compared with the xenograft and exhibited better fixation within the defect site (including less intramedullary and extraosseous migration) compared with both control group and xenograft group.This trend persisted on days 60 and 90.In the infected wound model, implantation of the composite was associated with reduced severity of inflammatory injury, including osteonecrosis (P = 0.001) and polymorphonuclear granulocyte infiltration (P = 0.001), compared with the xenograft. CONCLUSIONThe composite based on NFC, a xenograft, and BP adhesive exhibits osteoconductive and osteoinductive potential for bone defect repair in a rat model.The obtained results demonstrate high biocompatibility and a low incidence of complications, including composite migration.In a wound infected with Staphylococcus aureus, the composite provides favorable early resistance to infection-related injury.