Optical clearing of bone samples was carried out as previously described.[66 (link)] Briefly, fixed samples were dehydrated in a graded ethanol series, followed by incubation in ethyl cinnamate (Sigma). Optically cleared samples were immersed in ethyl cinnamate and imaged on a light sheet microscope (LaVision BioTec). Bone scaffolds were imaged using the 488 nm laser to detect calcein and the 561 laser to detect Cy3(+)-SNPs. Tibiae were imaged using the 488 nm laser to detect calcein and the 640 laser to detect Cy5(+)-SNPs. Arivis Vision4D and ImageJ were used to process light sheet microscopy images.