sallyj, nice question.
Is the fracture risk reduction rate also misrepresented in some studies by the role of BMD in FRAX risk calculation? Are the inorganic pyrophospate crystals deposited on the bone with the action of bisphosphonates opaque, or do they register density on DXA.

Osteonecrosis of the jaw is a rare adverse effect of bisphosphonates. But the mechanism of action of these drugs is in prevening the stage necessary for remodeling. We know that osteoblasts are most effective where the osteoclasts have cleared cracked and fractured bone. So we halt the regeneration of new bone and preserve older bone.