Recombinant human bone morphogenetic protein-2 and collagen for bone regeneration

The study reported describes a combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) and collagen (C) to regenerate bone. Unilateral critical-sized defects (CSDs) were prepared in radii of 32 skeletally mature New Zealand white rabbits, Rabbits mere divided evenly among four treatments: autograft, absorbable C (Helistat(R)), 35 mu g of rhBMP-2 combined with absorbable C (rhBMP-2/C), and untreated CSDs. The two euthanasia periods were 4 and 8 weeks. Radiographs were taken the day of surgery, every 2 weeks, and at term and the percent of radiopacity was measured. Data analysis revealed a time-dependent increase in the percent radiopacity with rhBMP-2/C. Histological examination revealed the rhBMP-2/C treatment regenerated osseous contour by 8,weeks. According to quantitative histomorphometry, the CSD and C groups had significantly less new bone than either autograft or rhBMP-2/C (p less than or equal to 0.05). The results suggest that rhBMP-2/C could be an effective therapy to restore segmental bone defects. (C) 1998 John Wiley & Sons, Inc.