ABSTRACT
The present study was designed to create a vascularized bone graft combining the osteogenetic
potential of bone marrow cells, and vascular bundle implantation in a hydroxyapatite
chamber, using New Zealand white rabbits. A hydroxyapatite chamber was molded into
a cylindrical shape, and hydroxyapatite fillers were soaked in an autogenous bone-marrow-cell
suspension at a concentration of 1.6 × 108/ml. In one group, the implant was packed with allogenic demineralized bone matrix
powder (DBM) and implanted in the mid-thigh subcutaneously, with the epigastric vessels
running through the chamber. In a second group, the chamber with bone marrow cells
and DBM was implanted subcutaneously, without vascular bundle implantation. The control
group consisted of a chamber without DBM, soaked in venous blood and implanted in
the opposite thigh, with the epigastric vessels running through the chamber.
Cross-sectional bone area and mineral apposition rate were measured, in addition to
newly-formed vessels. After 3 weeks, chambers implanted with bone marrow cells and
DBM demonstrated consistent bone formation in the pores of the chamber walls and within
the chambers. No evidence of bone formation was noted in the chambers soaked with
venous blood. The results indicated that vascular-bundle implantation promoted earlier
bone formation with neovascularization in the chambers with bone-marrow cells and
DBM. Microangiograms revealed vascular connections between the vascular bundle and
soft tissue surrounding the chamber through newly-formed vessels in the chamber wall.
These findings support the concept of creating a preformed vascularized bone graft,
to reconstruct segmental bone defects.
