Effects of BMP-2 on bone formation at palatal subperiosteal sites

Objectives: Recombinant human BMP-2 (rhBMP-2) has been demonstrated to induce bone formation, and it needs suitable scaffold for implantation. The purpose of this study was to evaluate the effects of rhBMP-2 with a bioabsorbable material, alginic acid gel (AG) on bone formation at palatal subperiosteal sites.

Methods: RhBMP-2(0.0, 0.1, 0.5, 1.0 µg/µl)with AG were injected into the palatal subperiosteal sites in 10-week-old Wister rats. The implant sites were separately divided into four groups according to the dosage of rhBMP-2: 0 µg, 0.1 µg, 0.5 µg and 1 µg. The rats were sacrificed at 3 weeks after implantation, followed by histopathologic observation and histometric evaluation of new bone. The Tukey-Kramer test was used for comparisons of new bone volume (NBV) among each group.

Results: Implants had disappeared at every group and new bone formation was observed at 0.1 µg, 0.5 µg and 1 µg. New bone was continuous with the original bone at 0.5 µg and 1 µg. NBV increased as the dosage increased from 0 µg to 0.5 µg (P<0.05), and did not significantly change as the dosage increased from 0.5 µg to 1 µg.

Conclusions: These results suggest that rhBMP-2 with AG has the ability to induce new bone formation, and its effects vary according to the dosage of rhBMP-2.