 Bone fractures or bone loss in specific sites are cases where a bone graft is sometimes needed to provide bone augmentation. For bone fractures, these are typically metaphyseal or maxillofacial fractures with risk of malunion or non-union. Bone loss can happen under various circumstances: it can be a consequence of a systemic disease like osteoporosis or of a surgical intervention like the extraction of a tooth or the removal of a bone cyst or tumor. 