Department of Restorative Dentistry, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Prosthetic Dental Science Department, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
J Appl Biomater Funct Mater. 2023 Jan-Dec;21:22808000231159238. doi: 10.1177/22808000231159238.
This study was aimed at including 2.5 wt.% of carbon nanoparticles (CNPs) and graphene oxide NPs (GNPs) in a control adhesive (CA) and then investigate the effect of this inclusion on their mechanical properties and its adhesion to root dentin.
Scanning electron microscopy and energy dispersive X-ray (SEM-EDX) mapping were conducted to investigate the structural features and elemental distribution of CNPs and GNPs, respectively. These NPs were further characterized by Raman spectroscopy. The adhesives were characterized by evaluating their push-out bond strength (PBS), rheological properties, degree of conversion (DC) investigation, and failure type analysis.
The SEM micrographs revealed that the CNPs were irregular and hexagonal, whereas the GNPs were flake-shaped. EDX analysis showed that carbon (C), oxygen (O), and zirconia (Zr) were found in the CNPs, while the GNPs were composed of C and O. The Raman spectra for CNPs and GNPs revealed their characteristic bands (CNPs-D band: 1334 cm, GNPs-D band: 1341 cm, CNPs-G band: 1650 cm, and GNPs-G band: 1607 cm). The testing verified that the highest bond strength to root dentin were detected for GNP-reinforced adhesive (33.20 ± 3.55 MPa), trailed closely by CNP-reinforced adhesive (30.48 ± 3.10 MPa), while, the CA displayed lowest values (25.11 ± 3.60 MPa). The inter-group comparisons of the NP-reinforced adhesives with the CA revealed statistically significant results ( < 0.01). Failures of adhesive nature were most common in within the adhesives and root dentin. The rheological assessment results demonstrated a reduced viscosity for all the adhesives observed at advanced angular frequencies. All the adhesives verified suitable dentin interaction shown by hybrid layer and appropriate resin tag development. A reduced DC was perceived for both NP-reinforced adhesives, compared to the CA.
The present study's findings have demonstrated that 2.5% GNP adhesive revealed the highest, suitable root dentin interaction, and acceptable rheological properties. Nevertheless, a reduced DC was observed (matched with the CA). Prospective studies probing the influence of diverse concentrations of filler NPs on the adhesive's mechanical properties to root dentin are recommended.
本研究旨在控制胶粘剂中添加 2.5wt.% 的碳纳米粒子（CNPs）和氧化石墨烯纳米粒子（GNPs），然后研究其添加对机械性能及其对根管牙本质粘结力的影响。
使用扫描电子显微镜和能量色散 X 射线（SEM-EDX）映射分别研究 CNPs 和 GNPs 的结构特征和元素分布。进一步通过拉曼光谱对这些纳米颗粒进行了表征。通过评估其推出粘结强度（PBS）、流变性能、转化率（DC）研究和失效类型分析来对胶粘剂进行表征。
SEM 显微照片显示，CNPs 呈不规则的六边形，而 GNPs 呈片状。EDX 分析表明，CNPs 中含有碳（C）、氧（O）和氧化锆（Zr），而 GNPs 则由 C 和 O 组成。CNPs 和 GNPs 的拉曼光谱显示了它们的特征带（CNPs-D 带：1334cm，GNPs-D 带：1341cm，CNPs-G 带：1650cm，GNPs-G 带：1607cm）。测试结果表明，与根管牙本质粘结强度最高的是 GNP 增强型胶粘剂（33.20±3.55MPa），其次是 CNP 增强型胶粘剂（30.48±3.10MPa），而 CA 显示的粘结强度最低（25.11±3.60MPa）。NP 增强型胶粘剂与 CA 之间的组间比较显示出具有统计学意义的结果（ < 0.01）。在胶粘剂和根管牙本质内最常见的失效类型是胶粘剂失效。流变学评估结果表明，所有胶粘剂在较高的角频率下观察到的粘度降低。所有的胶粘剂都证明了混合层和适当的树脂标记发展表现出合适的牙本质相互作用。与 CA 相比，两种 NP 增强型胶粘剂的 DC 降低。
本研究结果表明，2.5%GNP 胶粘剂具有最高的、合适的根管牙本质相互作用和可接受的流变性能。然而，观察到的 DC 降低（与 CA 匹配）。建议进行进一步的研究，以探究不同浓度的填充纳米颗粒对胶粘剂机械性能对根管牙本质的影响。
