Effects of enamel matrix proteins in combination with a bovine-derived natural bone mineral for the repair of bone defects

Previously, the use of enamel matrix derivative (EMD) in combination with a natural bone mineral (NBM) was able to stimulate periodontal ligament cell and osteoblast proliferation and differentiation. Despite widespread use of EMD for periodontal applications, the effects of EMD on bone regeneration are not well understood. The aim of the present study was to test the ability of EMD on bone regeneration in a rat femur defect model in combination with NBM. Twenty-seven rats were treated with either NBM or NBM + EMD and assigned to histological analysis at 2, 4, and 8 weeks. Defect morphology and mineralized bone were assessed by mu CT. For descriptive histology, hematoxylin and eosin staining and Safranin O staining were performed. Significantly more newly formed trabecular bone was observed at 4 weeks around the NBM particles precoated with EMD when compared with NBM particles alone. The drilled control group, in contrast, achieved minimal bone regeneration at all three time points (P < 0.05). The present results may suggest that EMD has the ability to enhance the speed of new bone formation when combined with NBM particles in rat osseous defects. These findings may provide additional clinical support for the combination of EMD with bone graft for the repair of osseous and periodontal intrabony defects.