Early Biological Fixation of Porous Implant Coated With Paste-Retaining Recombinant Bone Morphogenetic Protein 2

The aim of this study was to evaluate the period required for stable initial bone-implant fixation with recombinant human bone morphogenetic protein 2 (rhBMP-2) in the bone marrow of a rabbit model. The porous implants being coated with β-tricalcium phosphate/polylactide-polyethylene glycol paste with 15, 30, or 60 μg of rhBMP-2 (n = 10) were implanted into animals in 3 experimental groups. In 2 control groups, the test implants were coated without rhBMP or no paste. In all groups, the implant was inserted for 3 and 6 weeks. At 3 weeks after implantation, the BMP-treated implants in the 2 lower dose groups had significantly more bone ingrowth to the implant surface than did the control groups, and the greatest effect occurred in the 30-μg rhBMP-2 group animals.