These results indicate that the composite was efficacious as a carrier of rhBMP-2 and bone was formed in an adjacent area where rhBMP-2 was directly and in where no host bone exists. The bone quantity and quality in the BMP-2 group were significantly improved when compared to the results from the implant group, as the BMP-2 group showed significantly higher parameters of micro-CT for bone quantity, such as percent bone volume, trabecular thickness, and trabecular number in the newly formed bone, and significantly lower parameters for bone quality, such as trabecular separation and trabecular pattern factor. These results imply that the rhBMP-2 loaded powder gel composite strengthened osseointegration through new bone formation around the dental implant in the rabbit tibia model. In comparison, the hydrogel group showed even lower new bone formation than the implant group (although the difference was not statistically significant), indicating that the porous β-TCP microspheres acted as a barrier between the implant and the tissue surrounding the implant because the hyaluronic acid powder gel only shows osteoconductivity [29–31]. This phenomenon is evident in the histology results. The fact that fibrous tissue formation was observed between the implant and the bone means that, when only β-TCP microspheres and hyaluronic acid powder gel are implanted, the combination may negatively affect the osseointegration of an implant. In contrast, if β-TCP microspheres and hyaluronic acid powder gel are mixed with rhBMP-2 and injected, they are expected to strengthen the osseointegration of the dental implant by promoting significant formation of new bone through their action as carriers of rhBMP-2, even in an environment where a bone defect exists or bone quality is poor.