BONE-FORMATION IN THE GOAT MAXILLARY SINUS INDUCED BY ABSORBABLE COLLAGEN SPONGE IMPLANTS IMPREGNATED WITH RECOMBINANT HUMAN BONE MORPHOGENETIC PROTEIN-2

This study assessed the efficacy safely and technical feasibility of i nducing bone formation in an animal model of maxillary sinus floor aug mentation using recombinant human bone morphogenetic protein-2 (rhBMP- 2) impregnated on an absorbable collagen sponge (ACS). Bilateral antra l maxillary sinus floor elevation procedures were surgically performed in six adult female Alpine-Saanen goats. Bone formation in response t o the implant was evaluated using sequential radiographs, computerized tomography and gross pathologic and histologic analysis performed at necropsy. Computerized tomographic scans documented nonosseous radiopa city in both sinuses postimplantation. Sinuses implanted with rhBMP-2/ ACS subsequently demonstrated increasing radiopacity local to the impl ant site, while radiopacity of the negative control sinuses remained u nchanged or decreased. The results demonstrated the ability of an rhBM P-2/ACS implant to induce substantive new bone formation within the ma xillary sinus of goats without adverse sequelae. The rhBMP-2/ACS compo site implant may represent an acceptable alternative to traditional bo ne grafts and bone substitutes for maxillary sinus floor augmentation procedures in humans.