Nanjundasetty Jyothi Kashi, Nanda Soumyaranjan, Panuganti Venugopal, Marigowda Jayashankar Chatra
Department of Conservative Dentistry and Endodontics, Sri Siddhartha Dental College, Tumkur, Karnataka, India.
J Conserv Dent. 2013 Nov;16(6):503-8. doi: 10.4103/0972-0707.120952.
To comparatively evaluate the microleakage and microgap formation along the gingival margin in class II cavities restored with silorane resin composite and methacrylate resin composite with and without flowable resin liner.
Sixty human mandibular premolars were distributed into three groups, each group containing 20 teeth (n = 20). Mesial (subgroup A) and distal (subgroup B) box cavities were prepared with gingival margin above and below cemento enamel junction (CEJ), respectively, in each tooth and restored as follows - Group I - Silorane resin composite with self-etch primer and bond (Filtek P90, 3M ESPE MN, USA). Group II - Methacrylate resin composite (Filtek P60, 3M ESPE MN, USA) and self-etch adhesive (Adper Easy one, 3M ESPE MN, USA). Group III - Methacrylate resin composite with self-etch adhesive and a flowable resin liner (Filtek Z350 XT, 3M ESPE MN, USA). The teeth were thermocycled and immersed in 50% silver nitrate solution before sectioning. The specimens were observed under scanning electron microscope for dye penetration and microgap formation. The data was subjected to statistical analysis using Kruskal-Wallis test and Mann-Whitney U test using SPSS version 18.
Subgroup A in all the three groups showed significantly less microleakage and microgap formation compared to subgroup B with P < 0.05. Intergroup comparison of subgroup A did not show statistically significant difference, whereas subgroup B showed statistically significant difference for microleakage between group I and group II (P = 0.003), group III and group II (P = 0.002).
Silorane resin composite and methacrylate resin with liner showed significantly less microleakage in class II cavities along the gingival margin placed below CEJ compared to methacrylate resin without liner. All the study groups showed less microleakage and microgap formation along the gingival margin placed above CEJ.
比较评估使用硅烷化树脂复合材料和甲基丙烯酸酯树脂复合材料，在有或没有可流动树脂衬层的情况下，修复Ⅱ类洞时沿牙龈边缘的微渗漏和微间隙形成情况。
将60颗人类下颌前磨牙分为三组，每组20颗牙齿（n = 20）。在每颗牙齿上分别制备近中（A亚组）和远中（B亚组）盒状洞，牙龈边缘分别位于牙骨质釉质界（CEJ）上方和下方，并按以下方式修复——第一组：使用自酸蚀底漆和粘结剂的硅烷化树脂复合材料（Filtek P90，3M ESPE MN，美国）。第二组：甲基丙烯酸酯树脂复合材料（Filtek P60，3M ESPE MN，美国）和自酸蚀粘结剂（Adper Easy one，3M ESPE MN，美国）。第三组：使用自酸蚀粘结剂和可流动树脂衬层的甲基丙烯酸酯树脂复合材料（Filtek Z350 XT，3M ESPE MN，美国）。牙齿经热循环处理后，在切片前浸入50%硝酸银溶液中。在扫描电子显微镜下观察标本的染料渗透和微间隙形成情况。使用SPSS 18版软件，对数据进行Kruskal-Wallis检验和Mann-Whitney U检验的统计分析。
所有三组中的A亚组与B亚组相比，微渗漏和微间隙形成均显著更少，P < 0.05。A亚组的组间比较未显示出统计学显著差异，而B亚组在Ⅰ组和Ⅱ组（P = 0.003）、Ⅲ组和Ⅱ组（P = 0.002）之间的微渗漏显示出统计学显著差异。
与没有衬层的甲基丙烯酸酯树脂相比，硅烷化树脂复合材料和有衬层的甲基丙烯酸酯树脂在位于CEJ下方的Ⅱ类洞牙龈边缘处显示出显著更少的微渗漏。所有研究组在位于CEJ上方的牙龈边缘处均显示出更少的微渗漏和微间隙形成。
