Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Intern, Department of General Dentistry, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Microsc Res Tech. 2023 Jul;86(7):762-772. doi: 10.1002/jemt.24330. Epub 2023 May 2.
The aim was to formulate an experimental adhesive (EA) and added nanoparticles (NPs) of beta-tricalcium phosphate (β-TCP) to see the impact on pushout bond strength (PBS) and other mechanical properties. Three adhesives were prepared, including EA (control, without β-TCP NPs), 2.5%-β-TCP NPs containing adhesive (2.5%-NPA), and 5% β-TCP NPs containing adhesive (5%-NPA). For the characterization of the NPs, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy was accomplished. For the adhesive's characterization, rheological assessment, and degree of conversion (DC) analysis were performed. PBS of these adhesives against resin fiber post to root dentin, interfacial failure categories, and resin dentin interface analysis were also assessed. The β-TCP NPs were seen as agglomerated asymmetrical particles on SEM. These NPs were composed primarily of calcium (Ca), and phosphorus (P). Rheological evaluation of the adhesive's showed a drop in the viscosity of all adhesives at greater angular frequencies. The greatest DC was detected for the EA group (67.54 ± 7.9) followed by 2.5%-NPA group (45.32 ± 5.1), whereas the lowest DC values were seen for the 5%-NPA group (38.97 ± 6.5). Concerning PBS, the 2.5%-NPA revealed the highest values at the coronal (12.81 ± 3.0) and middle (8.50 ± 2.3) sections, whereas, for the apical section, the highest PBS values were seen for the 5%-NPA (4.9 ± 1.6). Most of the failures for all adhesive groups were seen at the adhesive-dentin interface (cohesive type failures) for all root segments (coronal, middle, and apical). The resin-dentin interface analysis verified hybrid layer and resin tag formation for all adhesives, but the presence of dispersed β-TCP NPs was only seen in the two NP-reinforced adhesives. The adding of β-TCP NPs in the adhesive could be beneficial as it could improve its PBS. Suitable rheological properties and dentin interaction were also observed for NP-reinforced adhesives. A reduced DC was seen for both β-TCP NP-containing adhesives as compared to the EA. RESEARCH HIGHLIGHTS: Experimental adhesives were reinforced with beta-tricalcium phosphate (β-TCP) nanocrystals. The β-TCP NPs were seen as agglomerated asymmetrical particles on SEM. These NPs were composed primarily of calcium (Ca), and phosphorus (P). β-TCP adhesives demonstrated superior pushout bond strength and a drop in the adhesive viscosity at greater angular frequencies compared to control adhesive. The greatest DC was detected for the EA group followed by 2.5%- β-TCP group, whereas the lowest DC values were for the 5%- β-TCP group.
目的是制备一种实验性胶粘剂（EA）并添加β-磷酸三钙（β-TCP）纳米颗粒（NPs），观察其对推出粘结强度（PBS）和其他机械性能的影响。制备了三种胶粘剂，包括 EA（对照，不含β-TCP NPs）、含 2.5%-β-TCP NPs 的胶粘剂（2.5%-NPA）和含 5%-β-TCP NPs 的胶粘剂（5%-NPA）。对 NPs 进行了扫描电子显微镜（SEM）和能量色散 X 射线（EDX）光谱分析。对胶粘剂进行了流变学评估和转化率（DC）分析。还评估了这些胶粘剂对树脂纤维桩与根管牙本质的 PBS、界面失效类型和树脂牙本质界面分析。SEM 上观察到β-TCP NPs 呈团聚的不对称颗粒。这些 NPs 主要由钙（Ca）和磷（P）组成。所有胶粘剂的流变学评估均显示在较大的角频率下，粘度下降。EA 组的 DC 值最大（67.54±7.9），其次是 2.5%-NPA 组（45.32±5.1），而 5%-NPA 组的 DC 值最低（38.97±6.5）。关于 PBS，2.5%-NPA 在冠部（12.81±3.0）和中部（8.50±2.3）显示出最高值，而在根尖部，5%-NPA 显示出最高的 PBS 值（4.9±1.6）。所有胶粘剂组的大部分失效都发生在所有根管段（冠部、中部和根尖部）的牙本质-胶粘剂界面（粘结型失效）。所有胶粘剂均验证了树脂-牙本质界面处的混合层和树脂标记形成，但仅在两种 NP 增强胶粘剂中观察到分散的β-TCP NPs。在胶粘剂中添加β-TCP NPs 可能是有益的，因为它可以提高 PBS。NP 增强胶粘剂还表现出合适的流变学特性和牙本质相互作用。与 EA 相比，两种含β-TCP NP 的胶粘剂的 DC 值均降低。研究亮点：实验性胶粘剂中加入了β-磷酸三钙（β-TCP）纳米晶体。SEM 上观察到β-TCP NPs 呈团聚的不对称颗粒。这些 NPs 主要由钙（Ca）和磷（P）组成。与对照胶粘剂相比，β-TCP 胶粘剂具有更高的推出粘结强度和较低的胶粘剂粘度，在较大的角频率下。EA 组的 DC 值最大，其次是 2.5%-β-TCP 组，而 5%-β-TCP 组的 DC 值最低。
