Materials and Methods: Orthodontic tooth movement was introduced 24 hours before transplantation of PL or ES cells, and rats were euthanized either 24 hours or 72 hours after cell transplantation.

• 材料和方法：在牙周膜细胞或者胚胎干细胞移植前24小时正畸移动小鼠牙齿，植入24或者72小时后安乐处死小鼠。