The efficacy of blood-derived growth factor source compared to bone-derived growth factor source on bone regeneration in critical-sized rabbit calvarial bone defects

BACKGROUND: The growth factor sources used in alveolar bone regeneration should be practical and at a level that provides maximum benefit and cost effectiveness. Autologous growth factors are easy and practical to obtain in clinical practice, but their effectiveness in bone regeneration should be assessed in vivo studies. The hypothesis of this study was that the contribution of bone derived growth factors source to bone formation is greater than that of blood-derived growth factor source. METHODS: Thirty male New Zealand rabbits were utilized in the experiment. Four defects of 8 mm were organized in the calvarium of each rabbit, and four treatment procedures were implemented: (1) empty defect, (2) autograft and xenograft (3) autograft+xenograft functionalized with growth factors released from autograft (4) autograft+ xenograft with injectable platelet rich fibrin (i-PRF). Rabbits were sacrificed at 4, 8 and 12 weeks of healing. Micro-computed tomography and histomorphometrically analyses were performed. The statistical difference was evaluated using two-way repeated measures analysis of variance. The significance level was set as p < 0.05. RESULTS: The autograft+xenograft, autograft+xenograft functionalized with growth factors released from autograft and autograft+ xenograft with i-PRF provided comparable bone formation at 4 and 8 weeks. The autograft+xenograft with i-PRF revealed significantly higher new bone formation at 12 weeks compared to that of autograft+xenograft group. (p = 0.016) There was no difference in the new bone formation between autograft+xenograft with i-PRF and autograft+xenograft functionalized with growth factors groups. (p = 0.75) The residual graft remained comparable among treatment groups at all time points. (p = 0.05) CONCLUSIONS: The composite graft contains growth factors obtained from i-PRF showed better new bone formation. Both blood and bone-derived growth factor sources can be utilized to functionalize the osteoconductive graft materials.