Surface Finish in Machining of Dental Ceramics

摘要

The five-axis machining of sculptured surface offers many advantages, including faster material removal rates, improved surface finish and elimination of hand finish. To implement a sophisticated five-axis computer-aided system for machining the dental ceramics, the required machining data for the numerical control of machining were investigated using special flat-end and sharp-end tools coated with diamond abrasives of different grit sizes. The major machining parameters include feed rate and depth of cut. The dental ceramics in this study was Vita Mark II commonly used for inlays, onlays and veneer restorations in the dental system. The surface quality of ceramics is examined and the relationship between surface roughness and machining parameters is revealed. The selection principles of tool and machining conditions were proposed based on the experimental results.