Stability of fatigued and aged ZTA compared to 3Y-TZP and AlO ceramic systems.

To evaluate the effect of fatigue and aging on the crystalline content and reliability of a zirconia-toughened-alumina (ZTA) composite compared to its individual counterpart materials (3Y-TZP and AlO). Thirty-six disc-shaped specimens per group were obtained to comply with ISO 6872:2015. Crystalline content, microstructure and reliability of experimental groups were evaluated in four stages: 1) immediate; 2) aged; 3) fatigued; 4) aged + fatigue.

Ultra-translucent zirconia processing and aging effect on microstructural, optical, and mechanical properties.

Objectives: To evaluate the effect of the ceramic processing and aging method on the microstructure, optical, and mechanical properties of a third generation ultra-translucent zirconia, yttria partially stabilized zirconia (5Y-PSZ).

Methods: In-house discs were obtained through uniaxial and isostatic pressing an ultra-translucent Y-PSZ powder and sintering at 1450 °C for 2 h. As control, a commercial disc was milled from pre-sintered blocks fabricated with the same 5Y-PSZ powder through isostatic pressing and sintered under the same protocol.

Performance of crowns cemented on a fiber-reinforced composite framework 5-unit implant-supported prostheses: in silico and fatigue analyses.

Objective: To characterize the biomechanical performance of fiber-reinforced composite 5-unit implant-supported fixed dental prostheses (FDPs) receiving individually milled crowns by insilico and fatigue analyses.

Methods: Eighteen implant-supported five-unit fiber-reinforced composite frameworks with an individually prepared abutment design were fabricated, and ninety resin-matrix ceramic crowns were milled to fit each abutment. FDPs were subjected to step-stress accelerated-life testing with load delivered at the center of the pontic and at 2nd molar and 1st premolar until failure.

Hydrothermal aging affects the three-dimensional fit and fatigue lifetime of zirconia abutments.

Objective: Evaluate the effect of aging using two different methods on the three-dimensional fit of zirconia abutments at the implant-abutment connection and estimate the probability of survival of anterior crowns supported by straight and 17-degree angled abutments.

Materials And Methods: Two different zirconia abutment designs, straight and 17-degree angled abutments (n = 63/group), were evaluated in the current study. The abutments were randomly allocated into three experimental groups according to laboratory aging condition (134°C, 2.

Physicochemical and mechanical characterization of a fiber-reinforced composite used as frameworks of implant-supported prostheses.

Objectives: To characterize the physicochemical and mechanical properties of a milled fiber-reinforced composite (FRC) for implant-supported fixed dental prostheses (FDPs).

Methods: For FRC characterization, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction, Fourier-transformed infrared spectrometry, simultaneous thermogravimetric analysis and differential scanning calorimetry were performed. For fatigue testing, 3-unit FRC frameworks were fabricated with conventional (9 mm connector area) and modified designs (12 mm connector area and 2.

Survival of implant-supported resin-matrix ceramic crowns: In silico and fatigue analyses.

Objective: To evaluate the fatigue survival, failure mode, and maximum principal stress (MP Stress) and strain (MP Strain) of resin-matrix ceramic systems used for implant-supported crowns.

Methods: Identical molar crowns were milled using four resin-matrix ceramics (n = 21/material): (i) Shofu Hard, (ii) Cerasmart (iii) Enamic, and (iv) Shofu HC. Crowns were cemented on the abutments, and the assembly underwent step-stress accelerated-life testing.

Failure Modes and Survival of Anterior Crowns Supported by Narrow Implant Systems.

The reduced hardware design of narrow implants increases the risk of fracture not only of the implant itself but also of the prosthetic constituents. Hence, the current study is aimed at estimating the probability of survival of anterior crowns supported by different narrow implant systems. Three different narrow implant systems of internal conical connections were evaluated (Ø3.

Hydrothermal degradation methods affect the properties and phase transformation depth of translucent zirconia.

Objectives: To characterize the optical and mechanical properties of a commercial and in-house translucent Y-TZP before and after aging in autoclave or hydrothermal reactor.

Methods: In-house experimental discs were obtained through uniaxial and isostatic pressing a translucent Y-TZP powder and sintering at 1,550 °C/1 h. Commercial discs were milled from pre-sintered blocks fabricated with the same powder through uniaxial and isostatic pressing and sintering.