Microstructure characterization and SCG of newly engineered dental ceramics

TLDR: The FEL and PIC discs showed the lowest susceptibility to slow crack growth (SCG), whereas the LD and ZLS discs presented the highest, and the overall strength and SCG of the new materials did not benefit from the additional phase or microconstituents present in them.

About: This article is published in Dental Materials.The article was published on 2016-07-01 and is currently open access. It has received 147 citations till now. The article focuses on the topics: Weibull modulus.

Figures

Fig. 4 – LD and ZLS microstructures. (A) LD without etching and (B) etched with 5% HF for 20 s, showing needle-like crystals (C and D), and ZLS etched with 5% HF for 20 s, showing rod-like crystals and charged areas (arrows) with the same composition as that of the non-charged areas. In comparison of the etched surfaces of B and D (same magnifications), one can see that the LD crystals are larger than the ZLS crystals, which are finer structures.

Table 1 – Cycle of crystallization of LD and ZLS ceramics.

Fig. 5 – (A) PIC, (B) FEL, (C) LD and (D) ZLS. Graphic representations of the means of strength at each stress rate and the inert strength. Steeper regression lines demonstrate higher susceptibility to SCG.

Fig. 6 – SEM images of fractured inert strength specimens. (A) FEL, (B) PIC, (C) LD, (D) ZLS. The arrows indicate the structural flaw on the tensile surface where failure initiated. H stands for “hackles”, which were the only noticeable fracture marking surrounding the zone of failure origin. In A, a semi-elliptical flaw led to fracture.

Fig. 1 – XRD spectra: (LD) lithium disilicate, (ZLS) lithium silicate reinforced by zirconia, (FEL) feldspathic ceramic and (

Table 2 – EDS analysis of bulk ceramic composition

Frequently asked questions

Q1. What are the contributions in "Microstructure characterization and scg of newly engineered dental ceramics" ?

The aim of this study was to characterize the microstructure of four dental CADCAM ceramics and evaluate their susceptibility to stress corrosion. Twenty-five specimens were further tested in mineral oil for determination of Weibull parameters.