Creation of 3D printed ASD models
The hollow model file was saved in standard tessellation language (STL). The printable STL files were imported into a high-precision 3D printer (JG AURORA Technology Co. Ltd, China, Shenzhen) to print the hollow 3D mold at a 1 :1 scale with the soluble material polyvinyl alcihol (PVA). The rubber like material, which has been utilize in the previous studies of our laboratory12, was used for filling the 3D hollow ASD mold. Then, the hollow mold was dissolved with warm water and the individualized soft ASD 3D model was obtained. (Fig.1D )