Abstract: Object: To establish digital simulated teeth roots for three dimensional printed scaffolds to preserve alveolar ridge after tooth extraction, and verify its similarity with the extracted teeth and the tooth socket. Methods: The left mandibular incisor was extracted with minimally invasion. The incisor and mandibles were scanned by Micro-CT, and a digital tooth model was established by 3D-DOCTOR software. The volume of incisor teeth, digital teeth model and teeth socket were calculated. The volume of digital teeth roots and teeth sockets were calculated by “hole filling” method. The real volume of incisor teeth was explored by flotage method. Then the data were compared to find the differences. Results: Three dimensional digital models of the skull, the left mandibular incisors and the mandibular teeth after extraction were constructed by 3D-DOCTOR software. There were no significant differences between the volume of teeth roots and digital teeth roots model (P>0.05). Both the volume of the teeth roots and that of the digital teeth were smaller than the volume of the teeth sockets (P<0.05). The volume of sockets were smaller before than after extraction (P<0.05). Conclusions: Digital simulated teeth roots for three dimensional printed scaffolds were successfully established, with high similarity to teeth roots. And its application will achieve better prognosis in alveolar ridge preservation.