For effective delivery of rhBMP-2, inorganic β-TCP microspheres were combined with an HA-based powder-like hydrogel, a natural polymer referred to as a “powder-gel” in this study. The aim of the present study was to evaluate if the powder gel composite showed slow release of rhBMP-2 and if it could act as an effective rhBMP-2 carrier for implantation in host bone with a bone defect or poor bone quality. In addition, the rabbit tibia implantation model was used to determine if the powder gel composite loaded with rhBMP-2 could strengthen the osseointegration of a dental implant.