Restorative Dentistry Departament, Faculty of Dentistry, Dental School, University of Chile, 8380544 Santiago, Chile; Graduate School, Faculty fo Dentistry , Universitity of Chile, 7500505, Santiago, Chile.
Department of Biochemistry, Federal University of Sao Paulo Molecular Biology Division, 04044-020 São Paulo, Brazil.
J Dent. 2024 Oct;149:105283. doi: 10.1016/j.jdent.2024.105283. Epub 2024 Aug 2.
The aim of this study was to evaluate the effect of an adhesive loaded with 0.2 % copper (Cu) and 5 % zinc oxide (ZnO) nanoparticles (Nps) on its adhesive properties and enzymatic activity at the hybrid layer ex vivo in a randomized clinical model.
Fifteen patients participated in this study, and a total of 30 third molars were used. Occlusal cavities (4 × 4 × 2 mm) were made in each tooth, and randomly divided into 2 groups: (i) Experimental group: commercial adhesive loaded with 0.2wt % CuNps and 5wt % ZnONps; and (ii) Control Group: non-loaded commercial adhesive. Teeth were restored with resin composite. Thirty days later, extractions were performed. Extracted teeth were longitudinally sectioned. Nps in powder were characterized by field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray (EDX) analysis. Microtensile bond strength (μTBS), degree of conversion (DC), and nanoleakeage (NL) tests were executed. In situ zymography (Zym) was performed to evaluate the gelatinolytic activity at the hybrid layer. Student's t-test (α = 0.05) was applied for all tests.
μTBS and DC did not show significant differences (p > 0.05) between both groups. However, NL and gelatinolytic activity at the hybrid layer showed significant values (p < 0.05) for experimental group in comparison with control group.
The addition of 0.2 % CuNps and 5 % ZnONps to a universal adhesive decreases NL and gelatinolytic activity at the hybrid layer, without jeopardizing its adhesive properties.
This randomized clinical trial with ex vivo analysis demonstrate that a commercial adhesive modified with 0.2wt % Cu and 5wt % ZnO Nps that does not affect its adhesive properties, reducing gelatinolytic activity and nanoleakage at the hybrid layer, which should contribute to an improvement of long term bonding-dentine clinical performance.
本研究旨在评估载有 0.2%铜（Cu）和 5%氧化锌（ZnO）纳米粒子（Nps）的胶粘剂在混合层中对其粘接力和酶活性的影响，这是在随机临床模型中进行的体外研究。
本研究共有 15 名患者参与，共使用 30 颗第三磨牙。在每个牙齿上制备 4×4×2mm 的咬合腔，并随机分为两组：（i）实验组：商用载有 0.2wt%CuNps 和 5wt%ZnONps 的胶粘剂；（ii）对照组：未加载的商用胶粘剂。用树脂复合材料修复牙齿。30 天后进行拔牙。取出的牙齿进行纵向切片。粉末中的 Nps 通过场发射扫描电子显微镜（FE-SEM）和能量色散 X 射线（EDX）分析进行表征。进行微拉伸粘结强度（μTBS）、转化率（DC）和纳米渗漏（NL）测试。进行原位酶谱（Zym）以评估混合层中的明胶酶活性。所有测试均采用学生 t 检验（α=0.05）。
两组间的 μTBS 和 DC 无显著差异（p>0.05）。然而，实验组 NL 和混合层中的明胶酶活性与对照组相比具有显著差异（p<0.05）。
在通用胶粘剂中添加 0.2%CuNps 和 5%ZnONps 可降低 NL 和混合层中的明胶酶活性，而不会影响其粘接力。
这项随机临床试验和体外分析表明，商用胶粘剂经 0.2wt%Cu 和 5wt%ZnO Nps 改性后，不会影响其粘结性能，降低混合层中的明胶酶活性和纳米渗漏，这有助于提高长期粘结-牙本质的临床性能。
