On a sliding genioplasty to increase vertical height as 5 mm What is the best material or type of graft for this?

on a sliding genioplasty to increase vertical height as 5 mm Bone grafts oneself. hip or skull? -graft bovine -some doctors use chin implants, as padding between the bones. (I'm not sure how this works) -hydoxyapatite block I have read that the best graft is self but some doctors tell me that alg hip graft is unpredictable and can change shape in the recovery or over time Are artificilaes grafts or biomaterials something healthy? What is the best material or type of graft for this?