Nasal dorsal augmentation with freeze-dried allograft bone.

Background: Properly prepared freeze-dried bone has been used with impunity by orthopedic surgeons since 1992 without a single report of disease transmission. The aim of this study was to evaluate freeze-dried cortical allograft bone for nasal dorsal augmentation.

Methods: Freeze-dried human cortical bone was obtained from DCI Donor Services, Nashville, Tennessee. Standards recommended by the American Association of Tissue Banks, the U.S. Food and Drug Administration, and the Centers for Disease Control and Prevention were followed. Objective evaluation of the persistence of graft volume was obtained by cephalometric radiography. Vascularization and incorporation of new bone elements within the grafts were demonstrated by using fluorine-18 sodium fluoride positron emission tomographic/computed tomographic scanning.

Results: The average persistence of projection in 18 patients was 87 percent at 6 months. Thereafter, 10 patients showed 100 percent maintenance of projection at 12 to 36 months. Vascularization and incorporation of new bone elements within the grafts were demonstrated by using fluorine-18 sodium fluoride positron emission tomographic/computed tomographic scanning in four patients.

Conclusions: The initial loss of 13 percent of projection is most likely attributable to resolution of early surgical edema. The authors postulate that there are two pathways based on whether the recipient bed allows vascular access to the graft. The revascularization or inductive pathway involves stem cell conversion to eventual osteoblasts. The scar bed barrier or noninductive pathway involves the preservation of the graft as an unchanged alloimplant. This report is the first of a series that will include a 5-year and a 10-year follow-up.