Comparison of bone regeneration in rabbit calvarial defects following the use of two different xenografts with a barrier membrane: A histological, histomorphometric, and micro-computed tomography study.

BACKGROUND: This study compared bone regeneration in rabbit calvarial defects using two different xenografts with a barrier membrane by histological, histomorphometric, and micro-computed tomography (micro-CT) analyses.

MATERIALS AND METHODS: This study was designed as a single-blind interventional experimental animal study that conducted on 20 male New Zealand rabbits. The rabbits were anesthetized, a full-thickness mucoperiosteal flap was elevated, and four bone defects with 8 mm diameter were created in their calvaria at the two sides of their midsagittal suture. Two defects were randomly filled with Bio-Oss and NOVA xenografts. The other two defects remained empty. Except for one control defect, the remaining three were covered with a resorbable membrane. Ten rabbits were sacrificed after 4 and the remaining 10 after 8 weeks. Histological sections underwent micro-CT and histological assessments for new bone formation, bone maturation, residual particles, degree of inflammation, foreign body reaction, and soft-tissue formation.

RESULTS: The percentage of new bone formation increased at 8 weeks compared with 4 weeks and had a similar trend in Bio-Oss and NOVA groups (P > 0.05). The percentage of new bone formation was slightly higher in defects with membrane at 8 weeks (P > 0.05). The newly formed bone was a combination of woven and lamellar bone in all groups (P > 0.05). Micro-CT showed no significant difference in bone microstructure. The difference in other parameters was not significant among the groups either (P > 0.05).

CONCLUSION: Considering the similar rate of new bone formation and residual particles, both Bio-Oss and NOVA may be successfully used as scaffold with a barrier membrane for regeneration of bone defects.