Bone 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. The goal was to compare qual. and quant. measures between OsteoStat vs. Bone wax. The porcine critical size defect model was chosen in this study. OsteoStat and Bone wax were introduced into sep. critical size defects located in the femur and humerus of a single porcine specimen. After a duration of 6 wk, the defect sites were harvested for clin., histol., and histomorphometric anal. Both groups had effective hemostatic action when introduced into the defects. Anal. of the histomorphometric data revealed that the amount of new bone was significantly greater at 6 wk in the OsteoStat group (38.05%) vs. 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. We 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 pos. results of OsteoStat compared to Bone wax. It is important that bone hemostat substances have biocompatible, osteoconductive, hemostatic, as well as good handling properties.