Biomaterials Department, Misr University for Science and Technology, Cairo, Egypt.
Biomaterials Department, Faculty of Dentistry, Cairo university, Cairo, Egypt.
Int Endod J. 2023 Sep;56(9):1129-1146. doi: 10.1111/iej.13949. Epub 2023 Jul 14.
Pulp vitality is essential for tooth integrity. Following pulp exposure, choosing a suitable pulp-capping material is crucial to maintain pulp vitality. However, the reparative dentine bridge created by calcium hydroxide (Ca(OH) ) is generally porous and incomplete. The aim of the current study is to assess the in vitro and in vivo bioactivities of nano eggshell-based slurry (NES), using NES as a direct pulp-capping material, compared with Ca(OH) in rabbit animal model.
Nano eggshell powder (NE) was characterized for particle morphology, chemical composition and ion release. In vitro bioactivity was tested by immersion in simulated body fluid (SBF) for 7 days. For histopathological evaluation, 36 adult New Zealand rabbits (72 pulp exposures) were divided into nine groups (n = 8) according to the pulp-capping material (NES, Ca(OH) and no capping as negative control group) and the animals were sacrificed after 7, 14 or 28 days. The pulps of the two lower central incisors were exposed and then directly capped by Ca(OH) or NES or left untreated. The cavities were then sealed with glass ionomer cement. Teeth were collected for histopathological evaluation using an optical microscope. Pulp haemorrhage, inflammation, fibrosis and calcific bridge formation were assessed. Results were statistically analysed using anova and Tukey's tests.
Nano eggshell particles were spherical with a 20 nm diameter and were composed mainly of calcite. Statistical analysis showed that there was a significant increase in the release of all investigated ions between days 1 and 28, except for copper. NES group showed a significantly higher release of all elements as compared to Ca(OH) . Environmental scanning electron microscope micrographs of NES incubated for 7 days in SBF showed the formation of HAp with a Ca/P ratio (1.686). For histopathological evaluation, the difference between groups was statistically significant. At day 28, 75% of the pulps of the Ca(OH) group showed mild calcific bridge in comparison with 100% moderate calcific bridge in the NES group. The NES group showed significantly less inflammation at days 7 and 28, and higher fibrosis at day 7 compared with Ca(OH) .
Nano eggshell-based slurry represents a promising novel direct pulp-capping material with favourable pulp tissue response.
牙髓活力对于牙齿的完整性至关重要。牙髓暴露后，选择合适的盖髓材料对于维持牙髓活力至关重要。然而，氢氧化钙（Ca(OH) ）所形成的修复性牙本质桥通常是多孔且不完整的。本研究旨在评估纳米蛋壳基浆料（NES）的体外和体内生物活性，将 NES 用作直接盖髓材料，并与兔动物模型中的 Ca(OH) 进行比较。
对纳米蛋壳粉末（NE）进行颗粒形态、化学成分和离子释放的特征分析。通过在模拟体液（SBF）中浸泡 7 天来测试体外生物活性。为了进行组织病理学评估，将 36 只成年新西兰兔（72 个牙髓暴露）根据盖髓材料（NES、Ca(OH) 和不盖髓作为阴性对照组）分为 9 组（n=8），然后将兔牙的两个下中切牙牙髓暴露，并用 Ca(OH) 或 NES 直接盖髓，或不做任何处理。然后用玻璃离子水门汀封闭窝洞。用光学显微镜收集牙齿进行组织病理学评估。评估牙髓出血、炎症、纤维化和钙化桥形成。使用方差分析和 Tukey 检验对结果进行统计学分析。
纳米蛋壳颗粒呈球形，直径为 20nm，主要由方解石组成。统计分析显示，除铜外，所有研究元素的释放量在第 1 天到第 28 天之间均有显著增加。与 Ca(OH) 相比，NES 组所有元素的释放量均显著增加。在 SBF 中孵育 7 天后的 NES 环境扫描电子显微镜照片显示形成了具有 Ca/P 比（1.686）的 HAp。对于组织病理学评估，各组之间的差异具有统计学意义。第 28 天，与 Ca(OH) 组 75%的牙髓表现为轻度钙化桥相比，NES 组 100%的牙髓表现为中度钙化桥。与 Ca(OH) 相比，NES 组在第 7 天和第 28 天的炎症明显减少，在第 7 天的纤维化程度更高。
纳米蛋壳基浆料是一种很有前途的新型直接盖髓材料，具有良好的牙髓组织反应。
