Microgrinding behaviour of dental glass-ceramics for restorations

Abstract

Current chairside CAD/CAM system produces unsatisfactory surface quality on dental restorations made from lithium metasilicate/disilicate glass-ceramics (LMGC/LDGC). This paper reports a microgrinding of these two materials at 1–5 μm depths of cut with Φ500 μm #320 and #600 diamond tools. The lowest 3D average roughness achieves 234±12 nm and 168±11 nm for LMGC and LDGC, respectively. They are 79% and 97% lower than current dental processes, and comparable to health human teeth. The materials removal mechanism includes both localized ductile removal and brittle fracture. This means fully-ductile removal is feasible on these materials by microgrinding and its potential to advance current dental manufacturing.