A study on the fabrication method of removable partial denture framework by computer-aided design and rapid prototyping

Purpose - The purpose of this paper is to explore an application of computer-aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as a prior stage to producing a sacrificial pattern for a removable partial denture (RPD) metal alloy framework. Design/methodology/approach - With the introduction of laser scan technology and commercial reverse engineering software, a standard plaster maxillary dental cast with dentition defect was successfully scanned and created as a STL-formatted digital cast With the software, the unwanted undercuts were eliminated based on the desired path of insertion. Parts of the RPD framework were then successfully custom-designed and combined as a whole. Findings - A sacrificial pattern was produced by rapid prototyping (RP) method and finally casted with chromium cobalt alloy. With suitable finishing process, both the sacrificial pattern and the casted framework fitted the cast well. Originality/value - The research indicated the feasibility of creating a library of RPD framework components. It is believed that, in the future, with the advance of the techniques, a totally new platform can be developed for the design and fabrication of custom-fit RPD framework based on the CAD/CAM/RP system.