Dynamic live imaging of bone: opening a new era with 'bone histodynametry'.

Recent advances in optical imaging with two-photon excitation microscopy have enabled visualization of the inside of intact bone tissues in living animals. Using these advanced techniques, the dynamic behaviors of live bone cells and static histological information on bone tissue structures can be elucidated. The migration and positioning of osteoclast precursor monocytes, the bone-resorbing function of mature osteoclasts, and its functional coupling with bone-replenishing osteoblasts have been evaluated, including their dynamic properties in intact live bones. This novel 'bone histodynametric' methodology, combined with conventional histomorphometric analyses, will surely contribute to opening of a new era in bone and mineral research.