Analysis of Bone Healing with a Novel Bone Wax Substitute Compared to Bone Wax in a Porcine Bone Defect Model
BackgroundBone wax is used in surgery as a hemostatic device for bone. Despite its good functional capacity as a bone hemostat, Bone wax materials often have very poor long-term interactions with bone. This study describes a novel composite of hydroxyapatite (HA) and biodegradable poly-lactic acid (PLA) with wax-like handling properties (OsteoStat). The goal was to compare qualitative and quantitative measures between OsteoStat versus Bone wax.\n\nMethodsThe porcine critical size defect model was chosen in this study. OsteoStat and Bone wax were introduced into separate critical size defects located in the femur and humerus of a single porcine specimen. After a duration of 6 weeks, the defect sites were harvested for clinical, histological, and histomorphometric analysis.\n\nResultsBoth groups had effective hemostatic action when introduced into the defects. Analysis of the histomorphometric data revealed that the amount of new bone was significantly greater at 6 weeks in the OsteoStat group (38.05%) versus the Bone wax group (11.88%), p=0.028. OsteoStat also demonstrated less soft tissue and less test material remaining in the defect sites; however, this was not statistically significant.\n\nConclusionsWe speculate that the incomplete biodegradation of Bone wax as well as its intrinsic inflammatory properties may have retarded osseous regeneration and promoted fibrosis. In contrast, well known biodegradation pathways for PLA combined with the HA component of OsteoStat may have accounted for the positive results of OsteoStat compared to Bone wax. It is important that bone hemostat substances have biocompatible, osteoconductive, hemostatic, as well as good handling properties.