Investigation of the effects of autogenous graft, concentrated growth factor and dentin graft on bone healing

Critical-sized bone defects are defined as defects that cannot spontaneously heal during an organism's lifetime and are instead filled with fibrous connective tissue. Due to their limited natural healing potential, various biomaterials, growth factors, and stem cell-based approaches are employed for treatment. While autogenous bone grafts are considered the gold standard for bone defect repair, dentin grafts have emerged as a promising alternative due to their similar organic-inorganic composition and the presence of growth factors. Additionally, concentrated growth factor (CGF), a platelet-derived product rich in growth factors, is known to accelerate bone regeneration when combined with grafts. This experimental animal study aims to compare the effects of autogenous bone grafts and non-demineralized dentin grafts on bone healing in critical-sized defects and to evaluate the potential synergistic impact of CGF supplementation on the regenerative process for both graft materials. Forty Wistar rats were used in the study. A 3 mm critical-sized defect was surgically created in the left femur of each rat. The animals were randomized into four equal groups: Group 1 (autogenous graft), Group 2 (autogenous graft + CGF), Group 3 (non-demineralized dentin graft), and Group 4 (non-demineralized dentin graft + CGF). The rats were sacrificed on postoperative day 28, and the samples were subjected to histological and immunohistochemical analyses. Histomorphometric evaluations included total healing area, new bone area, defect closure rate, residual graft material, osteoblast count, and osteoclast count. Immunohistochemical assessments measured VEGF and SPARK expression levels. The data were statistically analyzed. After a 28-day healing period, non-demineralized dentin grafts demonstrated statistically significant better outcomes in all evaluated parameters compared to autogenous bone grafts. Furthermore, CGF supplementation significantly enhanced bone regeneration for both autogenous and non-demineralized dentin grafts across all metrics. The most successful results were observed in Group 4 (non-demineralized dentin graft + CGF), which outperformed all other groups. This study demonstrates that non-demineralized dentin grafts promote more effective bone regeneration than autogenous bone grafts. Additionally, CGF supplementation significantly amplifies the regenerative efficacy of both graft types. These findings suggest that non-demineralized dentin grafts may serve as a viable alternative to autogenous grafts and that combining CGF with graft materials enhances their therapeutic potential in bone healing. Keyword: Critical size defect, CGF, Non-demineralised dentin graft, Autogenous bone grafting, Bone healing