The use of bi-layered all-ceramic crowns has continuously grown since the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia cores. Unfortunately, despite the outstanding mechanical properties of zirconia, problems related to porcelain cracking or chipping remain. One of the reasons for this is that ceramic copings are usually milled to uniform thicknesses of ...

In e-commerce transactions, the packaging level of porcelain, to a certain extent, determines loss rate goods in transportation process. Therefore, encouraging decisionmakers improve is key coordinating supply chain porcelain. Considering consumers’ preferences for level, this paper constructs three kinds porcelain decision-making models, including impact on transport losses and after-sales pro...

BACKGROUND Clinical studies reporting the outcome of zirconia-based restorations indicate that the strength of the zirconia frameworks is sufficient to withstand masticatory forces. However, a significant incidence of cohesive fracture of the veneering porcelain has been reported. The aim of this study was to investigate spontaneous crack development (chipping, rupture) in a range of porcelains...

Residual stress in the surface of dental porcelain was estimated using laser Raman spectroscopy. Sixteen different magnitudes of residual stress were generated in commercial porcelain disks by tempering, ion exchange, and slow cooling. The specimens were analyzed using a laser-Raman spectrometer with an Ar+ laser. The Raman shift of the largest peak near 500 cm-1 originating from silica was use...

STATEMENT OF THE PROBLEM Although all-ceramic restorations are broadly used, there is a lack of information concerning how their fit is affected by fabrication procedure and marginal configuration. PURPOSE The purpose of this study was to evaluate the marginal fit of zirconia CAD/CAM ceramic crowns before and after porcelain firing. The influence of finish line configuration on the marginal f...

The adhesion of porcelain to zirconia is a key factor in the success of bilayered restorations. In this study, the efficacy of a novel experimental liner (EL) containing zirconia for improved bonding between zirconia and veneering porcelain was tested. Four ELs containing various concentrations (0, 3.0, 6.0, and 9.0 wt %) of zirconia were prepared. Testing determined the most effective EL (EL3 ...

statement of problem: recent clinical results for zirconia all-ceramic restorations have revealed that the fracture rate 6-15% of the zirconia framework is so low and the core of zirconia has high stability. however, chipping-off fractures of porcelain are the most common reason for failures of zirconia in the fixed partial dentures. objectives: the purpose of this study was to compare the shea...