Digital denture manufacturing-An integrated technologies of abrasive computer tomography, CNC machining and rapid prototyping

The orthodontic denture produced by the traditional method is heavily relied on the skill and experience of the technician. Its quality is depended on the accuracy of the technician's subjective judgment. In addition, the manual process involves many steps that require a long time to complete. Most importantly, it does not preserve any quantitative information for future retrieval. In this paper, a novel device for scanning denture image and reconstructing 3D digital information of teeth models by abrasive computer tomography (ACT) is presented. The orthodontic denture is then to be produced by rapid prototyping (RP) or computer numerical control (CNC) machining methods based on the digital information. A force feedback sculptor (Freeform system, U.S.A.), using 3D touch technology, was applied to modify the teeth profile or features of the denture. It enables the dentist to perform digital manipulation of the denture profile with real-time and interactive operation. Due to its user-friendly human-computer interface, the dentist can directly access the 3-D model without relying on a CAD/CAM technician or denture technician. In this paper, the comparison between traditional manual operation and digital manufacture using RP and CNC machining technology for denture production is summarized. In this paper, a digital denture manufacturing protocol using an economic and harmless computer abrasive teeth profile scanning, computer-aided denture design, 3D touchable feature modification, and numerical denture manufacturing were proposed here. These proposed methods provide solid evidence that digital design and manufacturing technologies may become a new avenue for custom made denture design, analysis, and production in the 21th century.