Vascular osteomuscular autograft prefabrication using coral, type I collagen and recombinant human bone morphogenetic protein-2

In 20 male Sprague-Dawley rats, 10 pieces of L-shaped coral combined with t ype I collagen and recombinant human bone morphogenetic protein-2 (rhBMP-2) and 10 discs (diameter 5 mm) were wrapped in the gracilis muscle, and left pedicled on the femoral vessels. Untreated coral was buried in muscle at a distant control site in 4 animals. After 3 weeks, autografts were examined for the shape of new bone, vascular patency, and induction of bone. In all grafts in viable tissue, heterotopic bone was formed. The shape of the new bone was the same as that of the coral, and there was no significant infla mmatory reaction. Part of the coral in the composite was absorbed. Bone was not formed in any of the control sites. Coral and type 1 collagen are effe ctive as a carrier for BMP to prefabricate vascular osteomuscular autograft s with designed shape. There is a potential clinical application for BMP to bioengineer microvascular free flaps with intrinsic skeletal muscle for ma xillofacial reconstruction. (C) 2000 The British Association of Oral and Ma xillofacial Surgeons.