Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Republic of Korea.
BK21 PLUS Project, Yonsei University College of Dentistry, Seoul 03722, Republic of Korea.
Clin Oral Investig. 2021 Feb;25(2):497-505. doi: 10.1007/s00784-020-03409-y. Epub 2020 Jun 18.
This study investigated the effectiveness of acid etching and bond strength in an orthodontic bonding system in accordance with various time periods after 1.23% acidulated phosphate fluoride (APF) gel applications.
APF gel was applied on the enamel surface of bovine teeth, which were assigned to group F0. The tooth specimens were then immersed in distilled water for 1 (F1), 7 (F7), 14 (F14), 21 (F21) and 28 (F28) days. A group without fluoride pretreatment was a control group. All groups were etched with 35% phosphoric acid and evaluated using a surface hardness tester and scanning electron microscope (SEM). A shear bond strength (SBS) test was performed using a universal testing machine, and the bond failure modes were also examined.
After the 1.23% APF gel treatment, the hardness of the acid-etched enamel surface decreased as the immersion period increased. SEM images of the test groups showed etched patterns similar to control group as the immersion period increased. The SBS increased with increasing immersion period, whereas group F21 was not significantly different from the control group. Relatively high adhesive remnant index scores were identified as the ageing period increased.
The present study indicated that in order to obtain suitable bond strength, it is recommended to use an acid etching-based bonding system for the fixation of orthodontic appliances on the enamel surface 21 days after the use of APF gel.
Fluoride pre-treatment interferes with the acid etching effects on enamel, causing a reduction in the bond strength with orthodontic brackets.
本研究旨在探讨在应用 1.23%酸性磷酸氟凝胶后不同时间间隔下，酸蚀和粘结强度对正畸粘结系统的有效性。
将 APF 凝胶应用于牛牙釉质表面，将牙标本分为 F0 组。然后将牙齿标本分别浸泡在蒸馏水中 1（F1）、7（F7）、14（F14）、21（F21）和 28（F28）天。未进行氟预处理的组为对照组。所有组均用 35%磷酸酸蚀，并用表面硬度测试仪和扫描电子显微镜（SEM）进行评估。使用万能试验机进行剪切粘结强度（SBS）测试，并检查粘结失效模式。
在应用 1.23% APF 凝胶处理后，随着浸泡时间的增加，酸蚀釉质表面的硬度降低。随着浸泡时间的增加，试验组的 SEM 图像显示出与对照组相似的蚀刻图案。SBS 随着浸泡时间的增加而增加，而 F21 组与对照组无显著差异。随着老化时间的增加，相对较高的粘结残余指数得分被确定。
本研究表明，为了获得合适的粘结强度，建议在应用 APF 凝胶 21 天后，使用基于酸蚀的粘结系统固定正畸矫治器在釉质表面。
氟预处理会干扰酸对釉质的蚀刻效果，导致与正畸托槽的粘结强度降低。
