Dsouza Teena Sheethal, Shetty Aditya, Pais Kelvin Peter, Chikkanna Meenakumari, Almutairi Fahad Hamoud, Alharbi Yazeed Abdulaziz, Babu J Suresh, Swarnalatha C, Nayyar Abhishek Singh
Department of Conservative Dentistry and Endodontics, AB Shetty Memorial Institute of Dental Sciences, NITTE (Deemed to be University), Kankanady, Mangaluru, Karnataka, India.
Department of Public Health Dentistry, Faculty of Dentistry, Father Muller Medical College and Hospital, Kankanady, Mangaluru, Karnataka, India.
J Med Phys. 2024 Oct-Dec;49(4):642-647. doi: 10.4103/jmp.jmp_158_24. Epub 2024 Dec 18.
A wide range of dental materials have incorporated the concept of nanotechnology into their composition to enhance their physical and antimicrobial properties. In this pretext, silver nanoparticles (AgNPs) are among the most commonly used nanoparticles which are exceptionally noteworthy for their role in medical applications as an antibacterial agent. Another essential, desirable physical characteristic of all endodontic cements is their radiopacity, while in similar context, various radiopacifying agents such as bismuth oxide, barium sulfate, and even AgNPs have been incorporated in endodontic sealers to enhance their physical properties. The aim of the present study was to assess whether the incorporation of AgNPs and 10% bismuth oxide imparted the required radiopacity to the novel cement material (Nano CS) as per the requirement and standards laid by the International Organization for Standardization (ISO) guidelines and whether it complied with the ISO 6876:2001 specifications to achieve the necessary norms.
The structural characteristics of the novel cement material (Nano CS) were observed using energy-dispersive X-ray analysis under a Zeiss Gemini 500 Field Emission Scanning Electron Microscope, while radiopacity of the test material (Nano CS) was assessed with the help of an aluminum (Al) step-wedge using a nondestructive testing method following ISO guidelines. The optical density of the test material (Nano CS) was tested with the specimens of mineral trioxide aggregate (MTA) as the standard cement material along with the specimens of enamel and dentin that were 1 mm thick, and Al of appropriate thickness with the desired and equivalent radiopacity.
The findings of the present study suggested MTA to have higher radiopacity index equivalent to 4.56 ± 0.00 mm thickness of Al when compared to the test material (Nano CS) (2.78 ± 0.01 mm thickness of Al) and enamel (4.09 ± 0.01 mm thickness of Al) and dentin (2.01 ± 0.01 mm thickness of Al) specimens. Furthermore, the radiopacity index of test material (Nano CS) was found to be more when compared to dentin, though, less when compared to the enamel specimens with the results being statistically highly significant ( < 0.001).
The addition of nanosilver and bismuth oxide to the test material (Nano CS) imparted characteristic radiopacity, though the required specifications laid down by the ISO standards were not achieved. Increasing the concentration of the additives used might be considered to bring in the required radiopacity without having a significant impact on the physical and biological properties of the test material (Nano CS) intended to be used for endodontic applications.
多种牙科材料已将纳米技术概念融入其成分中，以增强其物理性能和抗菌性能。在此前提下，银纳米颗粒（AgNPs）是最常用的纳米颗粒之一，因其在医学应用中作为抗菌剂的作用而格外引人注目。所有根管充填水泥的另一个重要且理想的物理特性是其射线不透性，在类似情况下，各种射线不透性剂，如氧化铋、硫酸钡，甚至AgNPs已被添加到根管封闭剂中以增强其物理性能。本研究的目的是评估根据国际标准化组织（ISO）指南规定的要求和标准，将AgNPs和10%氧化铋添加到新型水泥材料（纳米CS）中是否能赋予其所需的射线不透性，以及它是否符合ISO 68:2001规范以达到必要的标准。
在蔡司Gemini 500场发射扫描电子显微镜下，使用能量色散X射线分析观察新型水泥材料（纳米CS）的结构特征，同时按照ISO指南，采用无损检测方法，借助铝（Al）阶梯楔评估测试材料（纳米CS）的射线不透性。以矿物三氧化物聚合体（MTA）标本作为标准水泥材料，以及1毫米厚的牙釉质和牙本质标本，连同具有所需且等效射线不透性的适当厚度的Al，测试测试材料（纳米CS）的光密度。
本研究结果表明，与测试材料（纳米CS）（相当于2.78±0.01毫米厚的Al）、牙釉质（4.09±0.01毫米厚的Al）和牙本质（2.01±0.01毫米厚的Al）标本相比，MTA具有更高的射线不透性指数，相当于4.56±0.00毫米厚的Al。此外，发现测试材料（纳米CS）的射线不透性指数与牙本质相比更高，不过与牙釉质标本相比更低，结果具有高度统计学显著性（<0.001）。
向测试材料（纳米CS）中添加纳米银和氧化铋赋予了其特征性的射线不透性，尽管未达到ISO标准规定的要求规格。可以考虑增加所用添加剂的浓度，以带来所需的射线不透性，同时对打算用于根管治疗应用的测试材料（纳米CS）的物理和生物学性能没有显著影响。
