In recent years,
Zirconia-reinforced
Lithium Silicate ceramic (ZLS), combining
lithium-
silicate and
zirconia features, has shown to have excellent mechanical and aesthetic characteristics. Thus, the aim of this study was to compare the fracture strength of ZLS single
crowns cemented with two different cementation techniques. Twenty
crowns were realised and cemented on teeth replicas achieved from an extracted premolar human tooth. The samples were divided into two groups of 10 specimens each, Glass-ionomeric cement (GIC) group and Self-Adhesive
Resin Cement (
ARC) group. The mechanical test was performed using a universal testing machine. The specimens were then evaluated with a scanning electron microscope (SEM) to identify for all
crowns and related abutments the pattern of fracture after the breaking point. The data obtained were statistically analysed. The mean fracture toughness values and standard deviations (±SD) were 2227 ± 382 N and 3712 ± 319 N respectively for GIC and
ARC groups. In fact, t-test showed a statistically significant difference between the two groups (p < 0.001). Moreover, the SEM results demonstrated portions of abutments still attached to the crown fragments in the
ARC group, whilst these were not present in the GIC group. Within the limitations of this study, these results suggest the use of adhesive cementation for ZLS
crowns, which significantly increase the compressive strength of ZLS restorations compared to GIC.