Sharafeddin Farahnaz, Feizi Negar
Professor, Department of Operative Dentistry, Biomaterial Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Postgraduate Student, Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
J Clin Exp Dent. 2017 Feb 1;9(2):e242-e248. doi: 10.4317/jced.53216. eCollection 2017 Feb.
Pulpal reaction to restorative materials depends on marginal microleakage, which is a dynamic phenomenon that allows bacteria and fluids to traverse across the tooth-restoration interface. Glass-ionomer cement (GIC) exhibits low microleakage due to direct bonding to tooth structures. Hydroxyapatite (HAP) based on the similarity with tooth structure may decrease the microleakage. The aim of this study was to evaluate marginal microleakage of a mixture of conventional and resin-modified glass-ionomer (RMGI) with micro- and nano-HAP.
In this study, 30 non-carious extracted human third molar teeth were used. Standard Cl V cavities were prepared on the buccal and lingual surfaces. The cavities were restored in six experimental groups as follows: group 1, conventional glass-ionomer cement (CGIC); group 2, CGIC with micro-HAP; group 3, CGIC with nano-HAP; group 4, RMGI; group 5, RMGI with micro-HAP; group 6, RMGI with nano-HAP. The restorations were finished and polished. The teeth were coated with nail polish, sealed with sticky wax, thermocycled and placed in a solution of 2% basic fuchsine for 24 hours. The teeth were sectioned and microleakage was measured. Kruskal-Wallis, Man-Whitney and Wilcoxon tests were used for data analysis (<0.05).
The data analysis revealed significantly lower microleakage in groups 5 and 6 at both occlusal and gingival margins. Also in these two groups the gingival microleakage was significantly lower than occlusal margin (=0.009 and =0.001 respectively), but in groups 1(CGIC) and 3(CGIC+ nano-HAP) and 4(RMGI) the microleakage of occlusal margin were significantly lower than that of gingival margin (=0.001, =0.007 and =0.001 respectively).
Mixing RMGI with nano-HAP and micro-HAP resulted in lower microleakage. Glass-ionomer, micro-hydroxyapatite, microleakage, nano-hydroxyapatite.
牙髓对修复材料的反应取决于边缘微渗漏，这是一种动态现象，可使细菌和液体穿过牙齿与修复体的界面。玻璃离子水门汀（GIC）由于能直接与牙齿结构结合，故微渗漏较低。基于与牙齿结构相似性的羟基磷灰石（HAP）可能会减少微渗漏。本研究的目的是评估传统玻璃离子水门汀（CGIC）与树脂改性玻璃离子水门汀（RMGI）分别与微米级和纳米级HAP混合物的边缘微渗漏情况。
本研究使用了30颗非龋性拔除的人类第三磨牙。在颊面和舌面制备标准的V类洞。将洞分为六个实验组进行修复：第1组，传统玻璃离子水门汀（CGIC）；第2组，含微米级HAP的CGIC；第3组，含纳米级HAP的CGIC；第4组，RMGI；第5组；含微米级HAP的RMGI；第6组，含纳米级HAP的RMGI。修复体完成后进行打磨抛光。牙齿用指甲油涂抹，用粘性蜡密封，进行热循环处理，然后置于2%碱性品红溶液中24小时。将牙齿切片并测量微渗漏情况。采用Kruskal-Wallis、Mann-Whitney和Wilcoxon检验进行数据分析（P<0.05）。
数据分析显示，第5组和第6组在咬合边缘和牙龈边缘的微渗漏均显著较低。而且在这两组中，牙龈边缘的微渗漏也显著低于咬合边缘（分别为P=0.009和P=0.001），但在第1组（CGIC）、第3组（CGIC+纳米级HAP）和第4组（RMGI）中，咬合边缘的微渗漏显著低于牙龈边缘（分别为P=0.001、P=0.007和P=0.001）。
RMGI与纳米级HAP和微米级HAP混合可降低微渗漏。玻璃离子水门汀、微米级羟基磷灰石、微渗漏、纳米级羟基磷灰石。
