Design and 3D printing of glass-ceramic/zirconia composite ceramics for dental application

Fluorapatite glass-ceramic (GC) and yttria-stabilized zirconia (YSZ) are two commonly used ceramic materials for dental prosthetic restorations. Fluorapatite GCs are known for their outstanding biocompatibility and aesthetic characteristics, moreover, they can release fluoride ions which have anticaries effect. Nevertheless, they often lack the requisite strength and toughness to withstand high occlusal forces. Conversely, YSZ exhibits remarkable mechanical properties, however, it is susceptible to excessive wear on opposing teeth. To address these limitations, a novel fluorapatite GC-YSZ composite ceramic was designed and formed through vat photopolymerization. The effect of composition ratios of fluorapatite GC particles and YSZ fibers (0˗40 wt% YSZ) on the forming precision, mechanical properties, and tribological compatibility with GC was thoroughly investigated. The results demonstrated that optimal comprehensive performance was achieved when the YSZ fiber content reached 40 wt%, which resulted in a fracture toughness of 1.68 MPa m1/2, marking a 98.8 % increase over pure GC. The specific wear rates of the sample and the antagonistic titanium ball were reduced by 75.6 % and 63.8 %, respectively, compared with GC. In addition, the dimensional accuracy error of the green body was reduced by approximately 44 %. The design and fabrication of GC-YSZ composites offer an approach for developing high-performance all-ceramic dental materials.