Bone remodeling of the modified vascularized free iliac flap in jaw reconstruction

Objective: This study investigates the postoperative bone remodeling patterns of the iliacbone after jaw reconstruction with the modified vascularized free iliac flap, which preserves the lateral cortical bone. Methods: Patients undergoing jawbone reconstruction with the modified vascularized free iliac bone flap between January 2022 and February 2023 were recruited. Maxillofacial spiral CT scans were collected at 1 week, 6 months, and 1 year postoperatively. The nascent cortical bone thickness, total bone thickness, and cancellous bone density of the iliac bone flap were measured at three specified planes on the spiral CT images. Results: Seven patients were recruited for bone remodeling analysis. Cortical bone regeneration was observed at the iliac bone in all patients. At 1 year postoperatively, the mean cortical bone thickening was 1.18 mm, 1.17 mm, and 1.01 mm at the three measurement planes, respectively. Significant increases were noted in the overall thickness of the iliac bone and the cancellous bone density were reduced significantly at 6 months compared to 1 week postoperatively. From 6 months to 1 year postoperatively, there was a slight increase in cortical bone thickness and a further decrease in cancellous bone density. Conclusion: The modified vascularized free iliac flap shows gradual increases in cortical bone thickness and total iliac bone thickness, along with a gradual decrease in cancellous bone density. The bone remodeling is more active in the first 6 months after surgery. The modified vascularized free iliac flap represents a viable alternative for jaw reconstruction. Clinical trial number: not applicable.