Combined effects of porous XXXX and demineralized bone matrix on bone induction: in vitro and in vivo study using a nude @entity35 model.

@entity1 @entity8087 @entity1711 @entity692 @entity1710 @entity35 @entity623
@entity692 (HA) is an osteoconductive material used as a bone graft extender and demineralized bone matrix (DBM) has been used as a source of osteoinductive factors. A combination of DBM and HA is expected to create a composite with both osteoconductive and osteoinductive properties. This study examined the effect of a combination of DBM and HA on osteogenesis both in vitro and in vivo using an athymic nude @entity35 abdominal muscle pouch model, and evaluated the possibility of HA as a carrier of DBM. @entity623 ( @entity623 ) staining, @entity623 assay and measurements of the mRNA expression of @entity623 and @entity8087 by RT-PCR were performed by transplanting @entity1 mesenchymal stem cells onto a plate. Five athymic nude @entity35 each were assigned to one of two experimental groups (DBM/HA putty and only HA, i.e. 15 pouches per group). The muscle pouches were filled with DBM/HA putty or only HA. Radiographs were obtained at weeks 4 and 8, postoperatively. The animals were sacrificed at week 8 postoperatively and high resolution microCT was used to confirm the newly formed mineralized tissue. Each pouch was fixed, embedded, sectioned and processed for @entity1710 and @entity1711 staining. The @entity623 value of the DBM/HA putty was higher than those of HA and control (p < 0.05, each). The expression of @entity623 mRNA appeared higher on the DBM/HA putty than on HA and control. MicroCT and histology examinations of the DBM/HA putty demonstrated the presence of newly generated mineralized tissues but there was no mineralized tissue in the HA cases. In conclusion, the DBM/HA putty indicated osteoblastic differentiation in vitro and showed ectopic mineralized tissue formation in the @entity35 abdominal pouch model. These findings indicate that the DBM/HA putty can retain its oteoinductivity and HA can be used as a carrier of DBM.
