Establishment Of Database In Dental CAD/CAM System And Research On Single Crown Design

Objective: With the rapid progress of the computer technology, the techniques of CAD/CAM are widely used in many fields. In the same way, the advances of CAD/CAM are providing a new option for dentistry, creating an alternative technique for producing dental restorations. In China, the research of the dental CAD/CAM is still in primitive stage. The study laid the foundation for the development of a dental CAD/CAM system with independent intellectual property by establishing the data bank of dental CAD/CAM system and exploring the CAD program of a single crown.Methods: 1. 28 standard tooth crowns were scanned by a 3-D mechanical scanner, the acquired data were processed and substituted with the average Chinese tooth crowns size data, characterized areas and points were defined on the surfaces of the virtual crowns, then the 3-D data bank of the 28 standard tooth crowns and the denture at intercuspided occlusion were reconstructed. 2. The gypsum model of the abutment tooth and the apposition mode of a patient were scanned by the mechanical scanner; they also scanned in centric occlusion. The acquired data were processed in I-DEAS program, and then the data of the crown fitting the peculiar patient were obtained and saved in IGES format that can be used by other programs, which can be compatible with machining process. Then the CAD program of a single crown was obtained.Results: 1.Obtained the 3-D data bank of the 28 standard Chinese tooth crowns which can be adjusted. 2. Obtained the denture at intercuspided occlusion. 3. Obtained the CAD program of a single crown, which provides foundation for the dental CAD/CAM system.Conclusion: 1. The precision and reliability of the computerized standard 3-Dtooth crowns and denture are well acceptable. The data can be adjusted. 2. The denture at intercuspided occlusion accord with anatomic characteristics .That lay the foundation for the CAD program of fixed bridge, and can be used in CAT (computer aided teaching). 3. The CAD program of a single crown is feasible. That provides foundation for the development of the dental CAD/CAM system.