Figure 1 Model of rapid maxillary expansion (RME) and three-dimensional reconstruction of the occlusal view of the rat maxilla. ( A ) Chemical Structure of Puerarin (C21H20O10). ( B ) Plaster model of rat maxillary. ( C ) Expansion appliance. ( D ) Inserted expansion appliance. ( E ) Bonded expansion appliance. ( F ) Rat maxillae after carefully dissected. ( G ) Rat head in the occlusal view, the vertical red line marking the occlusal position of the mid-coronal plane of the upper first molar, the horizontal red line marking the position of mid-palatal suture. ( H ) Rat head in the sagittal view, the red line marking the sagittal position of the mid-coronal plane of the upper first molar. ( I ) The distance of the mid-palatal suture in one of the rats in group 1 is 0.13mm. ( J ) The position and length of the ROI (2.0mm*1.0mm*0.8mm) in the coronal plane, horizontal plane, sagittal plane respectively. ( K ) 3D position view of ROI. ( L ) Location and plane of sectioning in the mid-palatal region.