Volumetric bone regenerative efficacy of biphasic calcium phosphate-collagen composite block loaded with rhBMP-2 in vertical bone augmentation model of a rabbit calvarium.
Block-type biphasic calcium phosphate (BCP) carriers are more effective at delivering recombinant human bone morphogenetic protein-2 (rhBMP-2) in various clinical situations than are particle-type carriers, due to their potential for highly successful three-dimensional bone regeneration. The aim of this study was to confirm the bone-regenerative capabilities of three-dimensional BCP blocks with a low hydroxyapatite/β-tricalcium phosphate ratio (20/80) combined with collagen (10% wt) as an rhBMP-2 delivery system in a craniofacial vertical bone augmentation model. BCP blocks and BCP-collagen blocks (with average macropore sizes of 296 and 390 μm, respectively) with or without rhBMP-2 were fixed with osteosynthesis screws to the calvarial surface of rabbits. After 8 weeks, histologic and histomorphometric analyses were performed to evaluate the resulting new bone area, augmented area, bone density, and degree of integration. The area of new bone was significantly greater in specimens containing rhBMP-2 than in the control group (p < 0.05). Moreover, the area fractions of newly formed bone within the augmented area and a degree of integration between the regenerative bone and the calvarium were both significantly greater in the BCP-collagen/rhBMP-2 group than in the BCP/rhBMP-2 group (p < 0.05), whereas the two carrier systems exhibited similar rhBMP-2 release profiles, with sustained and linear release. The BCP and BCP/rhBMP-2 blocks exhibited excellent structural integrity, with large fragments of residual ceramic. In conclusion, the BCP-collagen composite block exhibited enhanced osteoinductive potential and could be a good candidate as a carrier of rhBMP-2 due to its characteristics of favorable volumetric stability, ease of handling, and excellent remodeling properties.
Department of Periodontology, College of Dentistry, Yonsei University, Research Institute for Periodontal Regeneration, Seoul, Republic of Korea.
Jin-Woo
JW
Kim
Im-Hee
IH
Jung
Im-Hee
IH
Jeong
Kwang-Il
KI
Lee
Ui-Won
UW
Jung
Chang-Sung
CS
Kim
Seong-Ho
SH
Choi
Kyoo-Sung
KS
Cho
Jeong-Ho
JH
Yun
D000818:Animals; D015519:Bone Density / Q000187:drug effects; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology*; D001861:Bone Regeneration / Q000187:drug effects*; D002130:Calcium Phosphates / Q000494:pharmacology*; D003094:Collagen / Q000494:pharmacology*; D006801:Humans; D023421:Models, Animal; D010012:Osteogenesis / Q000187:drug effects; D016062:Porosity; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology; D012886:Skull / Q000187:drug effects* / Q000473:pathology*; D054457:Tissue Scaffolds / Q000737:chemistry; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C485817:beta-tricalcium phosphate; C499469:recombinant human bone morphogenetic protein-2; D003094:Collagen