Search

Aim: To establish whether the additional coating of titanium implants with Bone Morphogenetic Protein-3 (BMP-3) might enhance osseous integration., Method: Each of 15 cylindrical titanium test implants (Ti-6AI-4V) was coated using 230 micrograms porcine BMP-3. A further 15 implants with identical (corundium-blasted) surface served as negative controls. An uncoated and a BMP-3-coated test object were implanted into the femurs of 15 adult giant rabbits. New formation of bone around the implants was examined microscopically and histomorphometrically on postoperative days 14, 35 and 56., Results: Coated implants revealed superior osseointegration with statistical evaluation using the t-test for matched samples showing a significantly higher volume of new bone 5 weeks after surgery. Microscopic examination revealed osseointegration with no connective tissue membrane around the surface of the implants., Conclusions: Our results indicate that composite metal implants are suitable carriers for BMP-3 and that improved fixation of the implants can be achieved.

Introduction: The successful combination of osteoinductive factors with current materials used in both endoprosthetics and implantology improves bony ingrowth and long-term stability of the chosen implants. The aim of the present experimental animal study was to clarify in what way faster bony integration can be achieved through additional BMP-3-coating of titanium test implants of different surface textures (hydroxy-apatite-coated or corundum-blasted)., Methods: Thirty of 60 cylindrical titanium test implants with a hydroxy-apatite or corundum-blasted surface were coated with 230 microg porcine, high-purified BMP-3-precipitate per implant to check their osteoinductive potential in a bioassay. In each case a BMP-3-coated and an uncoated control-device were implanted with a gap formation of 1 mm into the femoral part of the patellofemoral joint of the right and left leg of 30 adult giant rabbits. Serial saw slices of all explanted specimens were prepared, and the osseous integration of the implant and time-dependent bone neoformation were analyzed microscopically and histomorphometrically 14, 35, and 56 days after implantation., Results: Coating of TiAl4V6-test devices with BMP-3 led in both groups after gap implantation to an improved osseointegration, that was histomorphological and histomorphometrical verifiable. Statistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of new formed bone of the BMP-3-coated corundum-blasted or hydroxy-apatite-coated TiAl4V6 test devices compared to the non-coated controls of the same type (P < 0.01). Light microscopy demonstrated osseointegration without connective tissue membrane around the surface of the implants after 2, 5, and 8 weeks. Better osseointegration was achieved in the hydroxy-apatite-coated implants than in the corundum-blasted implants., Conclusions: Our results indicate that composite metal implants, as used in endoprosthetics and implantology, are suitable carriers for BMP-3 and improved fixation of the implants can be achieved.