Abstract: A method for treating a bone defect is provided by identifying a bone site suitable for receiving an implant; and introducing a strongly resorbable, poorly crystalline apatitic calcium phosphate at the implant site, whereby bone is formed at the implant site. A bone defect may be treated by identifying a bone site suitable for receiving an implant; and introducing a hydrated precursor to a strongly resorbable, poorly crystalline apatitic calcium phosphate at the implant site, whereby the hydrated precursor is converted in vivo to a poorly crystalline apatitic calcium phosphate and whereby bone is formed at the implant site. The implant site may be a variety of sites, such as a tooth socket, non-union bone, bone prosthesis, an osteoporatic bone, an intervertebral space, an alveolar ridge or a bone fracture.