FIG. 4.

Micro-CT analysis of bone regeneration following implantation of MSC-CM or controls into a bone defect. (A) Rat calvarial bone defects before implantation of the materials. A bone defect of 5 mm in diameter was prepared in each parietal bone. (B) Micro-CT images of the calvaria 4 and 8 weeks after implantation of the indicated materials. In the PBS, DMEM(−), MSC-CM, and MSCs groups, the materials were implanted as a mixture with an agarose gel, while in the Defect group, the defect was left unfilled. (C) The area of newly regenerated bone in each defect 4 and 8 weeks after implantation of the materials. The area of the newly regenerated bone (mm²) was calculated for each of the experimental groups. The regenerated area is expressed as a percentage of the entire defect area. There were statistical differences between the area of the MSC-CM and that of the other groups both at 4 and 8 weeks except between the MSC-CM and MSCs groups at 8 weeks (p<0.05). Micro-CT, microcomputed tomography; PBS, phosphate-buffered saline.