Acid-insoluble human dentin as carrier material for recombinant human BMP-2

The aim of this study is to estimate the increase of bone‐inductive potency by human demineralized dentin matrix (DDM) with recombinant human bone morphogenetic protein‐2 (BMP‐2). Human teeth were crushed, completely demineralized in 0.6M HCl, and freeze‐dried. The tooth‐derived material is called DDM. The shape of DDM was a particle type and its size varied from 0.4 to 0.8 mm. The BMP‐2 dose‐dependent study in the rat subcutaneous tissues demonstrated that the volume of induced bone and marrow increased at a dose‐dependent manner. The time‐course study of bone induction by the BMP‐2 (5.0 μg)/DDM (70 mg) was estimated histologically and biochemically. Histological findings showed that the BMP‐2/DDM increased bone and marrow sequentially between the DDM particles. Calcium content in the BMP‐2/DDM‐induced tissue was compatible to the histological findings. ALP activity in the BMP‐2/DDM showed a maximal value at 1 week and gradually decreased. 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. We confirmed that BMP‐2 significantly accelerated bone formation in the acid‐insoluble human‐dentin carriers. These results indicate that human DDM should be an effective carrier for delivering BMP‐2 and superior scaffold for bone‐forming cells. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.