DOI: 10.11607/jomi.5959, PubMed ID (PMID): 29543927Pages 512-522, Language: EnglishKim, Yeon Jung / de Molon, Rafael Scaf / Horiguti, Fausto Rioiti / Contador, Guilherme Piragine / Coelho, Marco Antonio / Mascarenhas, Vinicius Ibiapina / de Souza Faloni, Ana Paula / Cirelli, Joni Augusto / Sendyk, Wilson RobertoPurpose: The objective of this investigation was to assess vertical bone augmentation using deproteinized bovine bone mineral (DBBM) infused or not with recombinant human bone morphogenetic protein (rhBMP-2) in rabbit tibiae.
Materials and Methods: A total of 18 female rabbits (New Zealand) received two blocks of DBBM in each tibia. The DBBM blocks were randomly assigned into four experimental groups: DBBM (only the bone graft); DBBM associated with absorbable collagen sponge (ACS); DBBM plus rhBMP-2 (1.5 mg/mL); and DBBM infused with rhBMP-2 (1.5 mg/mL) in an ACS carrier. Animals were sacrificed after 12 weeks, and the tibiae containing the DBBM blocks were dissected and analyzed radiographically (microcomputed tomography [micro-CT]), histologically, and immunohistochemically.
Results: Micro-CT analysis showed a considerable increase in bone volume (BV) and BV/tissue volume in the rhBMP-2/ACS group compared with all the others. Trabeculae thickness also increased in the rhBMP-2/ACS group compared with the DBBM/ACS group. Trabecular number, separation, and bone mineral density were not different among groups. Histomorphometric evaluation showed increased newly formed bone in the rhBMP-2/ACS group compared with the DBBM and DBBM/ACS groups. The amount of residual bone graft was statistically higher in the rhBMP-2 groups compared with the DBBM/ACS group. Immunohistochemical analysis showed that the vascular endothelial growth factor (VEGF) expression was more intense in the rhBMP-2/ACS group compared with the DBBM/ACS group. The immunopositivity for type 1 collagen tended to be higher in the two groups with rhBMP-2.
Conclusion: Collectively, the results of this study suggest that the addition of rhBMP-2 in an ACS carrier placed on top of the DBBM graft enhanced bone formation in this animal model.
Keywords: alveolar ridge augmentation, bone morphogenetic protein-2, bone transplantation, rabbits, recombinant human bone morphogenetic protein-2, x-ray microtomography