Shaymaa E Elsaka1, Amr M Elnaghy2. 1. Department of Dental Biomaterials, Faculty of Dentistry, Mansoura University, Mansoura, Egypt. Electronic address: shaymanaghy@mans.edu.eg. 2. Department of Conservative Dentistry and Endodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
Abstract
OBJECTIVE: The aim of this study was to assess the mechanical properties of recently introduced zirconia reinforced lithium silicate glass-ceramic. METHODS: Two types of CAD/CAM glass-ceramics (Vita Suprinity (VS); zirconia reinforced lithium silicate and IPS e.max CAD (IC); lithium disilicate) were used. Fracture toughness, flexural strength, elastic modulus, hardness, brittleness index, and microstructures were evaluated. Data were analyzed using independent t tests. Weibull analysis of flexural strength data was also performed. RESULTS: VS had significantly higher fracture toughness (2.31±0.17MPam(0.5)), flexural strength (443.63±38.90MPa), elastic modulus (70.44±1.97GPa), and hardness (6.53±0.49GPa) than IC (P<0.001). On the other hand, VS glass-ceramic revealed significantly a higher brittleness index (2.84±0.26μm(-1/2)) (lower machinability) than IC glass-ceramic (P<0.05). VS demonstrated a homogeneous fine crystalline structure while, IC revealed a structure with needle-shaped fine-grained crystals embedded in a glassy matrix. The VS glass-ceramic revealed a lower probability of failure and a higher strength than IC glass-ceramic according to Weibull analysis. SIGNIFICANCE: The VS zirconia reinforced lithium silicate glass-ceramic revealed higher mechanical properties compared with IC lithium disilicate glass-ceramic.
OBJECTIVE: The aim of this study was to assess the mechanical properties of recently introduced zirconia reinforced lithium silicate glass-ceramic. METHODS: Two types of CAD/CAM glass-ceramics (Vita Suprinity (VS); zirconia reinforced lithium silicate and IPS e.max CAD (IC); lithium disilicate) were used. Fracture toughness, flexural strength, elastic modulus, hardness, brittleness index, and microstructures were evaluated. Data were analyzed using independent t tests. Weibull analysis of flexural strength data was also performed. RESULTS: VS had significantly higher fracture toughness (2.31±0.17MPam(0.5)), flexural strength (443.63±38.90MPa), elastic modulus (70.44±1.97GPa), and hardness (6.53±0.49GPa) than IC (P<0.001). On the other hand, VS glass-ceramic revealed significantly a higher brittleness index (2.84±0.26μm(-1/2)) (lower machinability) than IC glass-ceramic (P<0.05). VS demonstrated a homogeneous fine crystalline structure while, IC revealed a structure with needle-shaped fine-grained crystals embedded in a glassy matrix. The VS glass-ceramic revealed a lower probability of failure and a higher strength than IC glass-ceramic according to Weibull analysis. SIGNIFICANCE: The VS zirconia reinforced lithium silicate glass-ceramic revealed higher mechanical properties compared with IC lithium disilicate glass-ceramic.
Authors: Taciana Emília Leite Vila-Nova; Isabelle Helena Gurgel de Carvalho; Dayanne Monielle Duarte Moura; André Ulisses Dantas Batista; Yu Zhang; Carlos Alberto Paskocimas; Marco Antonio Bottino; Rodrigo Othávio de Assunção E Souza Journal: Dent Mater Date: 2020-01-31 Impact factor: 5.304
Authors: Antonio Straface; Lena Rupp; Aiste Gintaute; Jens Fischer; Nicola U Zitzmann; Nadja Rohr Journal: Head Face Med Date: 2019-08-08 Impact factor: 2.151