Effect of enamel matrix derivative liquid in combination with a natural bone mineral on new bone formation in a rabbit GBR model.

Abstract

Recently, a new liquid carrier system for enamel matrix derivate (EMD-liquid) was developed with better physico-chemical properties for improved adsorption of EMD to biomaterial surfaces. The aim of the present study was to investigate the bone regenerative potential of EMD-liquid in combination with a natural bone mineral (NBM) in vivo. Four 6-mm defects were created in the calvaria of six New Zealand white rabbits. Defects were filled with either (1) control (empty), (2) 20mg of NBM, or (3) 20mg of NBM+20µl of EMD-liquid (n=8). All defects were covered with collagen barrier membranes. The bone regenerative potential was investigated by micro-CT and histomorphological analyses at 8weeks postsurgery. The mineralized tissue volume was significantly higher in the NBM+EMD-liquid group when compared to control, whereas no difference was observed between the NBM alone and control groups. While no significant difference was observed for horizontal bone defect closure between the NBM+EMD-liquid and the NBM alone groups, NBM+EMD-liquid significantly increased the total mineralized area and reduced the percentage of soft/connective tissue infiltration. No statistically significant difference was observed between the NBM+EMD-liquid group and NBM alone group for amount of mineralized bone. The addition of EMD-liquid did not lead to statistically significant bone formation when compared to NBM alone. The combination of NBM+EMD-liquid but not NBM alone did however induce superior mineralized tissues when compared to control (empty). Further research investigating the adsorption potential of EMD-liquid to bone-grafting particles with/without collagen may provide valuable insights into future regenerative strategies with enamel matrix proteins.