Department of Comprehensive Dentistry and Biomaterials, School of Dentistry, Louisiana State University Health Science Center, New Orleans, 70119, USA.
Acta Biomater. 2011 May;7(5):2293-302. doi: 10.1016/j.actbio.2011.01.028. Epub 2011 Jan 21.
The formation of organized nanocrystals that resemble enamel is crucial for successful enamel remineralization. Calcium, phosphate and fluoride ions, and amelogenin are important ingredients for the formation of organized hydroxyapatite (HAP) crystals in vitro. However, the effects of these remineralization agents on the enamel crystal morphology have not been thoroughly studied. The objective of this study was to investigate the effects of fluoride ions, supersaturation degree and amelogenin on the crystal morphology and organization of ex vivo remineralized human enamel. Extracted third molars were sliced thin and acid-etched to provide the enamel surface for immersion in different remineralization solutions. The crystal morphology and mineral phase of the remineralized enamel surface were analyzed by field emission-scanning electron microscopy, attenuated total reflection-Fourier transformed infrared and X-ray diffraction. The concentration of fluoride and the supersaturation degree of hydroxyapatite had significant effects on the crystal morphology and crystal organization, which varied from plate-like loose crystals to rod-like densely packed nanocrystal arrays. Densely packed arrays of fluoridated hydroxyapatite nanorods were observed under the following conditions: σ(HAP)=10.2±2.0 with 1.5±0.5 mg l(-1) fluoride and 40±10 μg ml(-1) amelogenin, pH 6.8±0.4. A phase diagram summarizes the conditions that form dense or loose hydroxyapatite nanocrystal structures. This study provides the basis for the development of novel dental materials for caries management.
形成类似于釉质的有序纳米晶体对于成功的釉质再矿化至关重要。钙、磷酸盐和氟离子以及釉原蛋白是体外形成有序羟基磷灰石（HAP）晶体的重要成分。然而，这些再矿化剂对釉质晶体形态的影响尚未得到彻底研究。本研究旨在探讨氟离子、过饱和度和釉原蛋白对离体再矿化人釉质晶体形态和组织的影响。提取的第三磨牙被切成薄片并酸蚀，以提供釉质表面，使其浸入不同的再矿化溶液中。用场发射扫描电子显微镜、衰减全反射傅里叶变换红外和 X 射线衍射分析再矿化釉质表面的晶体形态和矿物相。氟离子浓度和羟基磷灰石的过饱和度对晶体形态和晶体组织有显著影响，晶体形态和晶体组织从板状疏松晶体变为棒状紧密排列的纳米晶阵列。在以下条件下观察到氟化羟基磷灰石纳米棒的紧密排列阵列：σ（HAP）=10.2±2.0，氟离子浓度为 1.5±0.5mg l（-1），釉原蛋白浓度为 40±10μg ml（-1），pH 值为 6.8±0.4。相图总结了形成密集或疏松羟基磷灰石纳米晶体结构的条件。本研究为开发用于龋病管理的新型牙科材料提供了基础。
