Fatigue behavior of sintered, glazed and glass-infiltrated surfaces of 5Y-PSZ bonded plates.

This study evaluated the effect of different occlusal surface finishes (glaze and silica glass infiltration) on surface characteristics and fatigue behavior of partially stabilized zirconia (PSZ) plates adhesively bonded onto epoxy resin discs. PSZ disc specimens (n = 15; Katana blocks STML, Kuraray Noritake Dental) were produced (Ø = 10 mm; thickness = 1.2 mm) and allocated into 3 groups: As sintered (S), silica glass infiltration (SGI), and glaze application (G).

Adhesive Cementation of CAD/CAM Silica-based Ceramics: Effect of Adhesive Type and Long-term Aging on the Bond Strength to Composite Cement.

Purpose: To investigate the effect of adhesive type and long-term aging on the shear bond strength (SBS) between silica-based ceramics and composite cement (CC).

Materials And Methods: Lithium-silicate (LS), feldspathic (FD) and polymer-infiltrated ceramic (PIC) blocks were sectioned (10 x 12 x 2 mm) and divided into 24 groups considering the factors: "ceramics" (LS, FD, and PIC), "adhesive" (Ctrl: without adhesive; 2SC: 2-step conventional; 3SC: 3-step conventional; 1SU: 1-step universal), and "aging" (non-aged or aged [A]). After the surface treatments, CC cylinders (n = 15, Ø = 2 mm; height = 2 mm) were made and half of the samples were subjected to thermocycling (10,000) and stored in water at 37°C for 18 months.

Characterization of Microstructure, Optical Properties, and Mechanical Behavior of a Temporary 3D Printing Resin: Impact of Post-Curing Time.

The present study aimed to characterize the microstructure of a temporary 3D printing polymer-based composite material (Resilab Temp), evaluating its optical properties and mechanical behavior according to different post-curing times. For the analysis of the surface microstructure and establishment of the best printing pattern, samples in bar format following ISO 4049 (25 × 10 × 3 mm) were designed in CAD software (Rhinoceros 6.0), printed on a W3D printer (Wilcos), and light-cured in Anycubic Photon for different lengths of time (no post-curing, 16 min, 32 min, and 60 min).

Targeting bonding protocols to increase the bond between acrylic resin or 3D printed denture bases and prefabricated or 3D printed denture teeth.

Statement Of Problem: The difference in chemical composition between denture base resin and denture teeth requires the development of bonding protocols that increase the union between the materials.

Purpose: The purpose of this in vitro study was to evaluate the impact of different bonding protocols on the bond between heat-polymerized and 3-dimensionally (3D) printed acrylic resin denture bases and acrylic resin prefabricated and 3D printed artificial teeth.

Material And Methods: Four types of artificial teeth were evaluated: prefabricated acrylic resin (VITA MFT) and 3D printed (Cosmos TEMP, PRIZMA 3D Bio Denture, and PrintaX AA Temp) bonded to 20×24-mm cylinders of heat-polymerized (VipiWave) and 3D printed (Cosmos Denture, PRIZMA 3D Bio Denture, and PrintaX BB Base) denture bases.

Effect of Finishing Protocols on the Surface Roughness and Fatigue Strength of a High-Translucent Zirconia.

Purpose: In case of need for esthetical improvement of zirconia restorations, an individualization using extrinsic staining can be applied. This study aimed to evaluate the surface roughness and fatigue strength (survival) of high-translucency zirconia (3Y-TZP, YZ®HT, Vita Zanhfabrik) with extrinsic characterization and/or glaze.

Methods: Sixty (60) zirconia discs (12 × 1.

Interface adhesion on layered zirconia: Effects of the veneering ceramic material and veneering technique.

Purpose: To evaluate the effect of different veneering ceramics and veneering techniques on the bond strength to zirconia.

Materials And Methods: 3Y-TZP zirconia blocks were sliced into 60 slabs, polished, and sintered. Each slab received one ceramic cylinder (Ø = 3.

Preheated Composite as an Alternative for Bonding Feldspathic and Hybrid Ceramics: A Microshear Bond Strength Study.

Purpose: To evaluate the bond strength between alternative or conventional luting agents and indirect restorative materials.

Materials And Methods: Blocks of a polymer-infiltrated ceramic network (PICN, Vita Enamic) and a feldspathic ceramic (FEL, Vita Mark II) were sliced and divided according to the luting agent: resin cement (PICN-RC, FEL-RC), flowable composite (PICN-FC, FEL-FC), or preheated composite (PICN-PH, FEL-PH). The ceramic surfaces were polished, etched with 5% hydrofluoric acid for 60 s, and then a silane layer was applied.

Effect of Antirotational Two-Piece Titanium Base on the Vertical Misfit, Fatigue Behavior, Stress Concentration, and Fracture Load of Implant-Supported Zirconia Crowns.

This study investigated the effects of antirotational titanium bases on the mechanical behavior of CAD/CAM titanium bases used for implant-supported prostheses. The aim was to assess the impact on the marginal fit, fatigue behavior, stress concentration, and fracture load of implant-supported CAD/CAM zirconia crowns. Forty titanium implants were divided into two groups: those with antirotational titanium bases (ARs) and those with rotational titanium bases (RTs).

Effect of staining layer on roughness after progressive wear of monolithic ceramics.

Purpose: The aim of this study was to evaluate staining layer behavior applied to high-translucency zirconia (YZHT), feldspathic ceramics (FD), and zirconia-reinforced lithium silicate (ZLS) surfaces against different antagonists.

Methods And Materials: Monolithic ceramic discs (n = 120) (ø 12 mm; thickness, 1.2 mm; ISO 6872) were obtained, 30 from YZHT and FD, and 60 from ZLS CAD/CAM blocks (staining layer applied before or after the crystallization procedure).

Effect of Resin Cement at Different Thicknesses on the Fatigue Shear Bond Strength to Leucite Ceramic.

Objectives:  This study was performed to evaluate fatigue survival by shear test in the union of leucite-reinforced feldspathic ceramic using different cement thicknesses.

Materials And Methods:  Leucite-reinforced glass ceramics blocks were sectioned in 2-mm thick slices where resin cylinders were cemented. The samples were distributed in two experimental groups ( = 20) according to the cement thickness (60 and 300 μm).

Silica infiltration on translucent zirconia restorations: Effects on the antagonist wear and survivability.

Objective: To assess potential antagonist wear and survival probability of silica-infiltrated zirconia compared to glass-graded, glazed, and polished zirconia.

Methods: Table top restorations made of 3Y-TZP (3Y), 5Y-PSZ (5Y), and lithium disilicate (LD) were bonded onto epoxy resin preparations. Each zirconia was divided into five groups according to the surface treatment: polishing; glaze; polishing-glaze; glass infiltration; and silica infiltration.

Resin cement coating reverts the machining damage on the flexural fatigue strength of lithium disilicate glass-ceramic.

This study evaluated the effect of resin cement coating with high and low viscosities on the flexural fatigue strength of machined lithium disilicate glass-ceramic. Discs (IPS e.max CAD; Ivoclar Vivadent) were prepared and divided according to the surface condition (machining [M]-CEREC inLab; and polishing [P]-laboratory procedures), resin cement coating (with or without), and cement viscosity (high [H] and low [L]).

Effect of Surface-Etching Treatment, Glaze, and the Antagonist on Roughness of a Hybrid Ceramic after Two-Body Wear.

Stains and glaze are effective procedures for achieving an aesthetic smoothness on indirect restorations. Thus, the effect of surface-etching treatments previous to the stain layer and the glaze application on the occlusal and antagonist wear of a hybrid ceramic were evaluated against different antagonists. Disc-shaped samples were prepared from polymer-infiltrated ceramic network (PICN) blocks.

Effect of Porcelain-to-Zirconia Ratio and Bonding Strategy on the Biaxial Flexural Strength and Weibull Characteristics of a Stress-Free Bilayer CAD/CAM Ceramic System.

Purpose: To evaluate the biaxial flexural strength of different porcelain-to-zirconia thickness ratios and bonding strategies of a stress-free bilayer CAD/CAM ceramic system.

Materials And Methods: A total of 60 zirconia discs (diameter: 15 mm; thickness: 0.3 or 0.

Bioengineering Tools Applied to Dentistry: Validation Methods for In Vitro and In Silico Analysis.

This study aimed to evaluate the use of bioengineering tools, finite element analysis, strain gauge analysis, photoelastic analysis, and digital image correlation, in computational studies with greater validity and reproducibility. A bibliographic search was performed in the main health databases PUBMED and Scholar Google, in which different studies, among them, laboratory studies, case reports, systematic reviews, and literature reviews, which were developed in living individuals, were included. Therefore, articles that did not deal with the use of finite element analysis, strain gauge analysis, photoelastic analysis, and digital image correlation were excluded, as well as their use in computational studies with greater validity and reproducibility.

Implant-Abutment Misfit after Cyclic Loading: An In Vitro Experimental Study.

This study aimed to evaluate the influence of thermomechanical cycling (TMC) and type of abutment on the misfit and compressive strength of the implant−abutment interface. Forty 3.75-mm external hexagon implants with 25° angled abutments were divided into four groups (N = 10).

Sintering mode of a translucent Y-TZP: Effects on its biaxial flexure fatigue strength, surface morphology and translucency.

Objective: This investigation evaluated the effect of two sintering modes of a translucent zirconia (Y-TZP) on its surface roughness, topography, phase-transformation (t → m), translucency and biaxial flexure fatigue strength.

Materials And Methods: To do so, 50 Y-TZP discs (Ø = 15 mm; thickness = 1.2 mm; IPS e.

Fatigue strength of 5Y-FSZ: glazing and polishing effects.

Objective: The aim of this study was to evaluate the effect of four different finishing procedures on the fatigue strength of a fully stabilized zirconia (5Y-FSZ) material.

Materials And Methods: Disc-shaped specimens of a 5Y-FSZ (Katana UTML, Kuraray Noritake) were made (ISO 6872-2015), grinded with 600- and 1200-grit silicon carbide paper, sintered as recommended, and randomly assigned into four groups according to the finishing technique: C (control, as-sintered), P (polished with polishing rubbers), G (glaze application - powder/liquid technique), and PG (polished with polishing rubbers + glaze application - powder/liquid). Then fatigue strength (staircase method), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses were performed.

Interfacial Fracture Energy Between New Translucent Zirconias and a Resin Cement.

Purpose: To determine the interfacial fracture energy (IFE) and stress distribution of Brazil-nut-shaped specimens made of translucent zirconia and resin cement.

Materials And Methods: Three types of translucent zirconia were used: 3Y-TZP (high, Vita YZ HT), 4Y-TZP (super, Vita YZ ST), and 5Y-TZP (extra, Vita YZ XT). The adhesive surfaces were air abraded and 10-MDP-based resin cement was used.

Effect of Different Ceramic Materials on Fatigue Resistance and Stress Distribution in Upper Canines with Palatal Veneers.

Objective:  The aim of this study was to evaluate, by means of a fatigue life test, different ceramic materials used in palatal veneers to restore the canine guidance.

Materials And Methods:  Forty-five standardized anatomical preparations were made in extracted healthy human canines with 1.2 uniform thickness.

Influence of Framework Material and Posterior Implant Angulation in Full-Arch All-on-4 Implant-Supported Prosthesis Stress Concentration.

This study evaluated the influence of distal implants angulation and framework material in the stress concentration of an All-on-4 full-arch prosthesis. A full-arch implant-supported prosthesis 3D model was created with different distal implant angulations and cantilever arms (30° with 10-mm cantilever; 45° with 10-mm cantilever and 45° with 6-mm cantilever) and framework materials (Cobalt-chrome [CoCr alloy], Yttria-stabilized tetragonal zirconia polycrystal [Y-TZP] and polyetheretherketone [PEEK]). Each solid was imported to computer-aided engineering software, and tetrahedral elements formed the mesh.

Mechanical behavior and microstructural characterization of different zirconia polycrystals in different thicknesses.

Purpose: To characterize the microstructure of three yttria partially stabilized zirconia ceramics and to compare their hardness, indentation fracture resistance (IFR), biaxial flexural strength (BFS), and fatigue flexural strength.

Materials And Methods: Disc-shaped specimens were obtained from 3Y-TZP (Vita YZ HT), 4Y-PSZ (Vita YZ ST) and 5Y-PSZ (Vita YZ XT), following the ISO 6872/2015 guidelines for BFS testing (final dimensions of 12 mm in diameter, 0.7 and 1.

CAD-FEA modeling and fracture resistance of bilayer zirconia crowns manufactured by the rapid layer technology.

In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system.