Bone regeneration of biphasic calcium phosphate with varying methods of material preparation in rabbit calvarial defect

Abstract

The purpose of this study is to compare and evaluate the bone regeneration effect and histological result of BCP(biphasic calcium phosphate) with varying methods of material preparation in rabbit calvarial defect. Ten adult male New Zealand rabbits were used in the experiment. Four defects with diameter of 8mm each were formed at the rabbit calvaria and BCPs manufactured with each different material preparation methods were applied in three defects.A BCP used in the first coating group was prepared by coating beta-tricalcium phosphate on HA scaffold surface manufactured with Replica method. The second BCP used in the sacrificial group was prepared by manufacturing biphasic scaffold with sacrificial template method and the third BCP in the foaming group by manufacturing biphasic scaffold with direct foaming method.Four defects were classified as the followings. Group 1(control): bone grafts not applied, Group2 (Coating group): BCP preparation method was replica method and the ratio of hydroxyapatite/beta-tricalcium phosphate (HA/β-TCP) was 7:3. Group3 (Sacrificial group): BCP preparation method was Sacrificial template method and the ratio of HA/β-TCP was 3:7. Group4 (Foaming group): BCP preparation method was direct foaming method and the ratio of HA/β-TCP was 2:8. The animals used in the experiment were sacrificed at 2 week(N=5) and 8 week(N=5).In the histological and histometric measurement results, BCPs used in the three groups showed high space maintenance ability and stability of particles. Compared to the coating group, the sacrificial group and foaming group showed significantly high bone graft resorption rate and especially in the foaming group the largest bone graft resorption rate was shown at 2 and 8 week period and bone regeneration was very even. However, no significant statistical difference in resorption rate and bone regeneration between sacrificial and foaming groups was shown.