Toledano Manuel, Aguilera Fátima S, Osorio Estrella, Cabello Inmaculada, Toledano-Osorio Manuel, Osorio Raquel
Dental Materials Section, Faculty of Dentistry, University of Granada, Colegio Máximo de Cartuja s/n, 18071 Granada, Spain.
Biointerphases. 2015 Sep 15;10(3):031002. doi: 10.1116/1.4926442.
The aim of this study was to evaluate if mechanical cycling influences bioactivity at the resin-carious dentin interface after bonding with Zn-doped self-etching adhesives. Caries-affected dentin surfaces were bonded with: Clearfil SE bond (SEB), and 10 wt. % ZnO nanoparticles or 2 wt. % ZnCl2 were added into the SEB primer or bonding components. Bonded interfaces were stored during 24 h and then tested or submitted to mechanical loading. Microtensile bond strength was assessed. Debonded dentin surfaces were studied by field emission scanning electron microscopy. Remineralization of the bonded interfaces was evaluated through nanohardness (Hi) and Young's modulus (Ei), Raman spectroscopy/cluster analysis, and Masson's trichrome staining technique. New precipitation of minerals composed of zinc-base salts and multiple Zn-rich phosphate deposits was observed in samples infiltrated with the Zn-doped adhesives. At the hybrid layer, specimens treated with ZnO incorporated in the primer (SEB·P-ZnO), after load cycling, attained the highest Ei and Hi. Load cycling increased Ei at the bottom of the hybrid layer when both, SEB undoped and SEB with ZnCl2 included in the bonding (SEB·Bd-ZnCl2), were used. ZnO incorporated in the primer promoted an increase in height of the phosphate and carbonate peaks, crystallinity, relative mineral concentration, and lower collagen crosslinking. ZnCl2 included in the bonding attained similar results, but relative mineral concentration decreased, associated to higher crosslinking and restricted collagen maturation. In general, a substantial restoration of the mechanical properties of caries-affected dentin substrata occurred when SEB-Zn doped adhesives were used and load cycled was applied, leading to functional and biochemical remineralization.
本研究的目的是评估机械循环是否会影响与锌掺杂自酸蚀粘结剂粘结后树脂 - 龋坏牙本质界面的生物活性。将龋坏的牙本质表面与以下材料进行粘结：Clearfil SE bond（SEB），并将10 wt.% 的ZnO纳米颗粒或2 wt.% 的ZnCl₂ 添加到SEB底漆或粘结组分中。粘结界面储存24小时后进行测试或承受机械加载。评估微拉伸粘结强度。通过场发射扫描电子显微镜研究脱粘后的牙本质表面。通过纳米硬度（Hi）和杨氏模量（Ei）、拉曼光谱/聚类分析以及马松三色染色技术评估粘结界面的再矿化情况。在用锌掺杂粘结剂渗透的样品中观察到由锌基盐和多种富锌磷酸盐沉积物组成的新矿物质沉淀。在混合层，用底漆中掺入ZnO处理的试样（SEB·P-ZnO）在加载循环后获得了最高的Ei和Hi。当使用未掺杂的SEB以及粘结中包含ZnCl₂ 的SEB（SEB·Bd-ZnCl₂）时，加载循环会增加混合层底部的Ei。底漆中掺入的ZnO促进了磷酸盐和碳酸盐峰高度、结晶度、相对矿物质浓度的增加以及较低的胶原蛋白交联。粘结中包含的ZnCl₂ 获得了类似的结果，但相对矿物质浓度降低，这与更高的交联和受限的胶原蛋白成熟有关。总体而言，当使用SEB - 锌掺杂粘结剂并进行加载循环时，龋坏牙本质基质的机械性能得到了显著恢复，从而导致功能性和生化性再矿化。
