A Novel Method of Neo-osseous Flap Prefabrication: Induction of Free Calvarial Periosteum with Bioactive Glass

Abstract

Background Reconstruction of craniofacial bone defects is a primary focus of craniofacial surgery. Although autogenous bone grafts remain as the gold standard, alloplastic materials have also gained widespread popularity due to their off-the-shelf availability, ease of use, and durability. In addition to replacing the missing bone, some of these alloplastic materials have also been found to induce new bone formation. Objectives In this study, the phenomenon of neo-osseous induction with bioactive glass was investigated for different implant-soft tissue configurations. Materials and Methods Thirty-two male, Wistar albino rats were divided into four equally numbered study groups. In group 1 (FP), adipofascial groin flaps were prefabricated with free periosteal grafts. In group 2 (FPB), adipofascial groin flaps were prefabricated with free periosteal grafts and bioactive glass. In group 3 (FB), adipofascial groin flaps were prefabricated with bioactive glass. In group 4 (control), adipofascial groin flaps were not prefabricated. Morphometric analyses of the prefabricated structures were performed using micro-CT. The histologic properties of the ectopic ossification were assessed by using a modified scoring system. Results Group 1 (FP) showed the greatest rate of mature lamellar bone formation. Group 2 (FBP) showed the greatest amount of bone density and volume. However, the addition of bioactive glass in group 2 (FBP) decreased the rate of mature lamellar bone formation when compared with group 1 (FP). Ectopic ossification was not observed in the control group. Conclusion Bioactive glass can be successfully used in the prefabrication of vascularized compound structures for the reconstruction of complex bone defects. However, interference with the periosteal induction of mature lamellar bone formation should be taken into consideration, especially in pediatric bone defects, which primarily rely on spontaneous osteogenesis through periosteal induction.