Figure 4. The number of osteoclasts three days after injection of rhVEGF and rhM-CSF. (A) Group N: no injection and no experimental tooth movement. Groups V and M: only injection of 0.5 µg rhVEGF and 0.5 µg rhM-CSF without experimental tooth movement, respectively. Group VM: injection of rhM-CSF as well as rhVEGF without experimental tooth movement. No significant differences were found between V and M. Another group showed a significant difference. Significant differences in the numbers were found between P and V, and between M and VM. The total number of osteoclasts in group V and group M was almost equivalent to that in group VM. NS = not significant (* p < 0.05; n = 8). (B) Group T: experimental tooth movement with PBS. Groups VT and MT: injection of 0.5 µg rhVEGF and 0.5 µg rhM-CSF with experimental tooth movement, respectively. Group VMT: injection of rhM-CSF as well as rhVEGF with experimental tooth movement. The number of osteoclasts in group VT was almost equivalent to that in group MT. The number of osteoclasts in group VMT was significantly larger than that in groups T, VT, and MT. NS = not significant (** p < 0.01; * p < 0.05; n = 8). (C) The number of osteoclasts in groups VT and MT was significantly larger than that in groups V and M, respectively (* p < 0.05; n = 8).