There are four common sources of bone grafting material:Autogenous (your own bone)Xenograft (bone from an animal - typically cow)Allograft (bone from a human donor),Or a Synthetic material (usually derived from hydroxyapatite or tricalcium phosphate).They each heal in different ways but in general they provide a scaffold for your body to grow blood vessels into and over a period of months the graft begins to become solid.After 3-6 months most grafted sites are suitable to place implants. Autogenous bone is the gold standard and creates the closest thing to the original bone.