Surface property changes observed in zirconia during etching with high-concentration hydrofluoric acid over various immersion times.

This study investigated the degree of phase transformation, surface roughness, and bond strength of zirconia immersed for various times in a 40% hydrofluoric acid (HF) solution. Non-etched sintered zirconia specimens were used as the control, while experimental groups were etched with a 40% HF solution for 5, 10, 20, 40, 80, 160 and 320 min. In each of the control and experimental groups, five specimens for X-ray diffraction analysis, four for surface morphology and surface roughness analysis, and ten for bonding strength measurement were used.

Image sensors using thin-film absorbers.

Image sensors are must-have components of most consumer electronics devices. They enable portable camera systems, which find their way into billions of devices annually. Such high volumes are possible thanks to the complementary metal-oxide semiconductor (CMOS) platform, leveraging wafer-scale manufacturing.

Change of phase transformation and bond strength of Y-TZP with various hydrofluoric acid etching.

Objectives: The purpose of this study was to quantify phase transformation after hydrofluoric acid (HF) etching at various concentrations on the surface of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP), and to evaluate changes in bonding strength before and after thermal cycling.

Materials And Methods: A group whose Y-TZP surface was treated with tribochemical silica abrasion (TS) was used as the control. Y-TZP specimens from each experimental group were etched with 5%, 10%, 20%, and 40% HF solutions at room temperature for 10 minutes.

Changes in Bond Strength and Topography for Y-TZP Etched with Hydrofluoric Acid Depending on Concentration and Temperature Conditions.

: This study aimed to investigate the change in bond strength between resin cement and tetragonal zirconia polycrystalline stabilized with 3 to 8 mol% yttrium oxide (Y-TZP) and observe the topographical change of the Y-TZP surface when etched with hydrofluoric acid (HF) solution under different concentration and temperature conditions. : Non-etched sintered Y-TZP specimens under two different temperature conditions (room temperature and 70-80 °C, respectively), were used as a control, while experimental groups were etched with 5%, 10%, 20%, and 40% HF solutions for 10 min. After zirconia primer and MDP-containing resin cement were applied to the Y-TZP surface, the shear bond strength (SBS) of each experimental group was measured.

Effect of hydrofluoric acid-based etchant at an elevated temperature on the bond strength and surface topography of Y-TZP ceramics.

Objectives: This study investigated the effects of a hydrofluoric acid (HA; solution of hydrogen fluoride [HF] in water)-based smart etching (SE) solution at an elevated temperature on yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramics in terms of bond strength and morphological changes.

Materials And Methods: Eighty sintered Y-TZP specimens were prepared for shear bond strength (SBS) testing. The bonding surface of the Y-TZP specimens was treated with 37% phosphoric acid etching at 20°C-25°C, 4% HA etching at 20°C-25°C, or HA-based SE at 70°C-80°C.

Effects of different silica-based layer coatings on bond strength of Y-TZP to bovine dentin.

This study investigated the effects of different silica-based layer coatings on shear bond strength (SBS) between Y-TZP and bovine dentin. Three different silica-based layer coatings were applied to the Y-TZP surface: tribochemical silica coating, vitrification (glaze coating), and composite resin sintering. A silane coupling agent (SIL) was applied to the silica-coated Y-TZP surface in the presence or absence of hydrofluoric acid (HF) treatment.

The effect of continuous application of MDP-containing primer and luting resin cement on bond strength to tribochemical silica-coated Y-TZP.

Objectives: This study investigated the effect of continuous application of 10-methacryloyloxydecyldihydrogen phosphate (MDP)-containing primer and luting resin cement on bond strength to tribochemical silica-coated yttria-stabilized tetragonal zirconia polycrystal (Y-TZP).

Materials And Methods: Forty bovine teeth and Y-TZP specimens were prepared. The dentin specimens were embedded in molds, with one side of the dentin exposed for cementation with the zirconia specimen.

Effect of Lithium Disilicate Reinforced Liner Treatment on Bond and Fracture Strengths of Bilayered Zirconia All-Ceramic Crown.

This study was performed to evaluate the effect of a lithium-disilicate spray-liner application on both the bond strength between zirconia cores and heat-pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of all-ceramic zirconia crowns. A lithium-disilicate reinforced liner was applied on the surface of a zirconia core and lithium-disilicate glass-ceramic was veneered on zirconia through heat press forming. Microtensile and crown fracture tests were conducted in order to evaluate, respectively, the bonding strength between the zirconia cores and heat pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of bilayered zirconia all-ceramic crowns.

Removal efficacy and cytotoxicity of a calcium hydroxide paste using -2-methyl-pyrrolidone as a vehicle.

Objectives: This study investigated the removal efficacy and cytotoxicity of a newly developed calcium hydroxide paste (cleaniCal, Maruchi) using -2-methyl-pyrrolidone (NMP) as a vehicle in comparison with ApexCal (Ivoclar Vivadent) and Calcipex II (Nishika), which use different vehicles such as polyethylene glycol and propylene glycol, respectively.

Materials And Methods: Thirty maxillary premolars with oval-shaped canals were divided into 3 groups and the teeth were filled with one of the pastes. After removal of the paste, micro-computed tomographic (μ-CT) imaging was obtained to assess the volume of residual paste in the root canal of each tooth.

Differentiating spontaneous vertical root fracture in endodontically treated tooth.

Although vertical root fracture (VRF) is mostly found in endodontically treated teeth, it also occurs spontaneously. If VRF is recognized after endodontic treatment, it is considered to be iatrogenic and can lead to legal trouble. However, legal problems can be averted if the dentist can prove that the VRF existed before endodontic treatment.

Effect of adhesive luting on the fracture resistance of zirconia compared to that of composite resin and lithium disilicate glass ceramic.

Objectives: The purpose of this study was to evaluate the effect of adhesive luting on the fracture resistance of zirconia compared to that of a composite resin and a lithium disilicate glass ceramic.

Materials And Methods: The specimens (dimension: 2 mm × 2 mm × 25 mm) of the composite resin, lithium disilicate glass ceramic, and yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) were prepared. These were then divided into nine groups: three non-luting groups, three non-adhesive luting groups, and three adhesive luting groups, for each restorative material.

In vitro evaluation of a newly produced resin-based endodontic sealer.

Objectives: A variety of root canal sealers were recently launched to the market. This study evaluated physicochemical properties, biocompatibility, and sealing ability of a newly launched resin-based sealer (Dia-Proseal, Diadent) compared to the existing root canal sealers (AHplus, Dentsply DeTrey and ADseal, Metabiomed).

Materials And Methods: The physicochemical properties of the tested sealers including pH, solubility, dimensional change, and radiopacity were evaluated.

Tooth discoloration induced by a novel mineral trioxide aggregate-based root canal sealer.

Objectives: The aim of this study was to evaluate tooth discoloration caused by contact with a novel injectable mineral trioxide aggregate (MTA)-based root canal sealer (Endoseal; Maruchi, Wonju, Korea) compared with a widely used resin-based root canal sealer (AHplus; Dentsply De Trey, Konstanz, Germany) and conventional MTA (ProRoot; Dentsply, Tulsa, OK, USA).

Materials And Methods: Forty standardized bovine tooth samples were instrumented and divided into three experimental groups and one control group (n = 10/group). Each material was inserted into the cavity, and all specimens were sealed with a self-adhesive resin.

Effects of epicatechin, a crosslinking agent, on human dental pulp cells cultured in collagen scaffolds.

Objective: The purpose of this study was to investigate the biological effects of epicatechin (ECN), a crosslinking agent, on human dental pulp cells (hDPCs) cultured in collagen scaffolds.

Material And Method: To evaluate the effects of ECN on the proliferation of hDPCs, cell counting was performed using optical and fluorescent microscopy. Measurements of alkaline phosphatase (ALP) activity, alizarin red staining, and real-time polymerase chain reactions were performed to assess odontogenic differentiation.