Highly toughened translucent glass matrix nanoceramics enhanced by amorphous Al <sub>2</sub>O <sub>3</sub>
Huasi Zhou, Yan Liu, Le Fu, Håkan Engqvist, Wei Xia
Abstract
The introduction of glass matrix ceramics in dental restorations has revolutionized dental aesthetics. A key challenge in the development of dental glass ceramics is achieving nanocrystalline glass ceramics with superior mechanical properties without compromising translucency. In this study, ZrO<sub>2</sub>–SiO<sub>2</sub> glass ceramics doped with amorphous Al<sub>2</sub>O<sub>3</sub> were investigated to address these requirements. The results indicate that the segregation of Al<sup>3+</sup> at the grain boundaries of ZrO<sub>2</sub> crystallites and the nano-domains of amorphous Al<sub>2</sub>O<sub>3</sub> significantly influences the microstructure, including the grain size and stabilization of tetragonal ZrO<sub>2</sub>, as well as the translucency and mechanical properties. The composition with 10 mol% Al<sub>2</sub>O<sub>3</sub> exhibits the highest toughness of 8.05 MPa∙m<sup>1/2</sup> while maintaining excellent translucency. Moreover, the composition with 5 mol% Al<sub>2</sub>O<sub>3</sub> demonstrates lower translucency but achieves a high flexural strength of 960 MPa. Overall, the mechanical properties of these translucent glass matrix ceramics surpass those of commercially available dental glass ceramics, highlighting their potential for dental restoration applications.