Which low-fusing porcelain glaze treatment technique is better to promote a vitreous surface on Y-TZP ceramic?

OBJECTIVE: to evaluated the influence of two types of low-fusing porcelain glaze application on the surface of a zirconia ceramics stabilized by yttrium (Y-TZP).METHODS: Y-TZP specimens were divided into five groups (n=5) according the surface treatments: control (CO), no treatment was performed; application of a thin low-fusing porcelain glass layer by the powder/liquid technique (GPL); GPL followed by 10% hydrofluoric acid (HF) etching (GPL-HF); glaze spray application (GS); GS followed by 10% HF etching (GS-HF). Roughness measurements contact angle, x-ray diffraction, energy-dispersive spectroscopy (EDS) and scanning electron microscope (SEM) analysis were performed.RESULTS: ANOVA and Tukey tests revealed that GPL had significantly lower contact angle values than the other groups (GPL:50.31º; GPL-HF: 72.73º; GS-HF: 81.73º; CO: 96.48º; GS:101.30º; p=0.001). GPL-HF presented a significant higher roughness (Ra/Rq: 2658.0/3367.0 ηm; p=0.001) than the other groups (GPL: 872.1/1162.0 ηm; GS-HF: 383.0/603.6 ηm; GS: 303.4/391.3 ηm; CO:263.4/339.1 ηm). The X-ray diffraction analysis just tetragonal phase in all groups. EDS and SEM analysis show a highest amount of silica on GPL and GPL-HF surface.CONCLUSION: the application of the low-fusing porcelain glaze by the powder/liquid technique followed by the HF etching promoted a better surface to micromechanical and chemical adhesion.

Low-Fusing Porcelain Glaze Application on 3Y-TZP Surfaces can Enhance Zirconia-Porcelain Adhesion

The aim of this study was to assess whether surface treatment improves zirconia-porcelain adhesion. The 3Y-TZP blocks were cut into squares, then polished and sintered. The zirconia surface treatments were performed as follows: no treatment (C); tribochemical silica coating (TBS); glaze application + hydrofluoric acid etching (GA); glaze application + hydrofluoric acid etching + silanization (GAS); deposition of silica nanofilm (NF). After treatments, veneering porcelain cylinders (3.3 x 3.3 mm) were built up on all specimens and fired. Then the specimens were subjected to thermal cycling (6000 cycles), and subjected to shear test. Fractures were analyzed by stereomicroscopy and SEM. Data were statistically analyzed by 1-way ANOVA and Tukey's test (5%). Zirconia-porcelain bond strength was affected by the ceramic surface treatments (p=0.0001). GA (19.5±3 MPa) and GAS (16.2±4 MPa) recorded the highest bond strength values, while control group had the lowest bond value (10.1±4 MPa). Adhesive failure of the samples predominated. Therefore, glaze application as 3Y-TZP treatment before veneering porcelain stratification may enhance zirconia-porcelain adhesion.

The fast and direct characterization of blue-and-white porcelain glaze from Jingdezhen by laser ablation-inductively coupled plasma mass spectrometry

A fast and direct characterization of blue-and-white porcelain glaze from Jingdezhen is proposed using laser ablation-inductively coupled plasma mass spectrometry.