Biochemical and histo-morphometrical analyses of bone and cartilage induced by human decalcified dentin matrix and BMP-2

Abstract

The aim of this study was to evaluate the hard tissue-inductive capability by human decalcified dentin matrix (DDM) with or without recombinant human bone morphogenetic protein-2 (BMP-2). Human teeth were crushed, completely decalcified and freeze-dried. We named the material DDM. The shape of DDM was a particle type and its size varied from 0.4 to 0.8 mm. The hard tissue induction by 70 mg of DDM was estimated histologically in the nude mice subcutaneous tissue at 4 weeks after implantation. The DDM alone induced bone and cartilage, independently, in the back skin. In addition, the time-course of bone induction by BMP-2 (5.0 μg)/DDM (70 mg) was analyzed in the rat subcutaneous tissues. Histological findings showed that the BMP-2/DDM induced bone and marrow between the DDM particles. Calcium content in the BMP-2/DDMinduced tissue was compatible to the histological findings. The morphometric analysis demonstrated that the BMP-2/DDM showed 66.9%, 79.0% in the volume of bone and marrow, and 32.4%, 21.0% in that of DDM at 8, 32 weeks, respectively. These results indicate that human DDM particles are osteo-chondroinductive and absorbable matrics. Human DDM are effective biomaterials of BMP-2 delivering for bone engineering.