Yu Mi-Kyung, Oh Eun-Jin, Lim Myung-Jin, Lee Kwang-Won
Department of Conservative Dentistry, Jeonbuk National University School of Dentistry, Jeonju, Korea.
Research Institute of Clinical Medicine Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Korea.
Restor Dent Endod. 2021 Oct 20;46(4):e54. doi: 10.5395/rde.2021.46.e54. eCollection 2021 Nov.
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.
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. First, to quantify the phase transformation, Y-TZP specimens ( = 5) treated with TS, 5%, 10%, 20% and 40% HF solutions were subjected to X-ray diffraction. Second, to evaluate the change in bond strength before and after thermal cycling, zirconia primer and MDP-containing resin cement were sequentially applied to the Y-TZP specimen. After 5,000 thermal cycles for half of the Y-TZP specimens, shear bond strength was measured for all experimental groups ( = 10).
The monoclinic phase content in the 40% HF-treated group was higher than that of the 5%, 10%, and 20% HF-treated groups, but lower than that of TS-treated group ( < 0.05). The 40% HF-treated group showed significantly higher bonding strength than the TS, 5%, and 10% HF-treated groups, even after thermal cycling ( < 0.05).
Through this experiment, the group treated with SiO containing air-borne abrasion on the Y-TZP surface showed higher phase transformation and higher reduction in bonding strength after thermal cycling compared to the group treated with high concentration HF.
本研究旨在量化不同浓度氢氟酸（HF）蚀刻后钇稳定四方多晶氧化锆（Y-TZP）表面的相变，并评估热循环前后结合强度的变化。
将一组经摩擦化学二氧化硅磨蚀（TS）处理的Y-TZP表面作为对照。各实验组的Y-TZP试样在室温下用5%、10%、20%和40%的HF溶液蚀刻10分钟。首先，为了量化相变，对经TS、5%、10%、20%和40%HF溶液处理的Y-TZP试样（n = 5）进行X射线衍射分析。其次，为了评估热循环前后结合强度的变化，将氧化锆底漆和含MDP的树脂水门汀依次应用于Y-TZP试样。对一半的Y-TZP试样进行5000次热循环后，测量所有实验组的剪切结合强度（n = 10）。
40%HF处理组的单斜相含量高于5%、10%和20%HF处理组，但低于TS处理组（P < 0.05）。即使在热循环后，40%HF处理组的结合强度也显著高于TS、5%和10%HF处理组（P < 0.05）。
通过本实验，与高浓度HF处理组相比，Y-TZP表面经含SiO的空气磨蚀处理的组在热循环后表现出更高的相变和更高的结合强度降低。
