Scaffold is necessary for tooth regeneration. Sponges made from polyvinyl alcohol with formalin cross-linking (PVF sponge) were used as scaffolds for bone formation in vitro and in vivo. Wells of cell culture plates and PVF sponge were coated with dextran to promote bone marrow cell attachment. Calcified tissue was formed conspicuously in wells coated with dextran of 10 kDa at 2 g/dl and of 500 kDa at 4 g/dl with dexametason, in vitro. In vivo bone formation was conspicuously observed in sponges coated by dextran of 10 kDa at 2 g/dl and of 500 kDa at 4 g/dl. Quantity of Ca was 129.20±19.69 µg/scaffold and that of osteocalcin was 25.28±5.71 ng/scaffold. These values suggest that many stem cells would attach in PVF sponge via dextran.