Fig. 5

Exosomes from cells treated with magnetic stimulation increased bone formation in critical-sized rat calvarial defects. (*) p < 0.05, (**) p < 0.01, (***) p < 0.001. a Coronal (upper panel) and sagittal (lower panel) micro-CT images of bone formation in each group after 12 weeks. b Quantitative comparison of BMD, BV/TV ratio, trabecular number and trabecular thickness in the different groups. c, d HE staining and Masson’s trichrome staining in the four groups. The lower panels are the magnification of yellow box; the black arrows indicate the vascular structures and red marrow aggregation; OB, old bone; NB, new bone