Abstract: Objective:To fabricate an all-ceramic crown which copies the morphology of preoperative tooth in one patient with only small occlusal dentin defects with completely digital design(CDD) technology, and to find a more precise and feasible solution to fix the tooth detect. Methods:The tooth treated with root canal therapy had the complete axial surface and small occlusal dentin defects. In order to keep the morphology of preoperative tooth, the digitized crown was designed with the information of preoperative tooth by oral scanning with CS3500 and using the "Biogeneric Copy" function of exocad design software, then the digitized information of the teeth was collected and transformed and the simulate zirconia crown was mode by 3D colloidal deposition technique. The patient's comfort and satisfaction were investigated by observing the morphology, the interproximal contacts, and the occlusion of crown. Results:The morphology of definitive restoration was similar to the preoperative tooth, which presented good interproximal contact and occlusion, and the patient was greatly satisfied without discomfort and foreign body sensation. Conclusion:A more accurate and personalized restoration approach can be implemented with the application of CDD to fabricate new ceramic crowns which copy the preoperative tooth.

Key words: biogeneric copy, oral scanning, tooth defect, restoration, completely digital design