Miletic Vesna, Peric Dejan, Milosevic Milos, Manojlovic Dragica, Mitrovic Nenad
University of Belgrade, School of Dental Medicine, DentalNet Research Group, Rankeova 4, 11000 Belgrade, Serbia.
University of Pristina, School of Medicine, Dental Clinic, Anri Dinana St., 38220 Kosovska Mitrovica, Serbia.
Dent Mater. 2016 Nov;32(11):1441-1451. doi: 10.1016/j.dental.2016.09.011. Epub 2016 Sep 26.
To compare strain and displacement of sculptable bulk-fill, low-shrinkage and conventional composites as well as dye penetration along the dentin-restoration interface.
Modified Class II cavities (N=5/group) were filled with sculptable bulk-fill (Filtek Bulk Fill Posterior, 3M ESPE; Tetric EvoCeram Bulk Fill, Ivoclar Vivadent; fiber-reinforced EverX Posterior, GC; giomer Beautifil Bulk, Schofu), low-shrinkage (Kalore, GC), nanohybrid (Tetric EvoCeram, Ivoclar Vivadent) or microhybrid (Filtek Z250, 3M ESPE) composites. Strain and displacement were determined using the 3D digital image correlation method based on two cameras with 1μm displacement sensitivity and 1600×1200 pixel resolution (Aramis, GOM). Microleakage along dentin axial and gingival cavity walls was measured under a stereomicroscope using a different set of teeth (N=8/group). Data were analyzed using analyses of variance with Tukey's post-test, Pearson correlation and paired t-test (α=0.05).
Strain of TEC Bulk, Filtek Bulk, Beautifil Bulk and Kalore was in the range of 1-1.5%. EverX and control composites showed 1.5-2% strain. Axial displacements were between 5μm and 30μm. The least strain was identified at 2mm below the occlusal surface in 4-mm but not in 2-mm layered composites. Greater microleakage occurred along the gingival than axial wall (p<0.05). No correlation was found between strain/displacements and microleakage axially (r=0.082, p=0.821; r=-0.2, p=0.605, respectively) or gingivally (r=-0.126, p=0.729, r=-0.278, p=0.469, respectively).
Strain i.e. volumetric shrinkage of sculptable bulk-fill and low-shrinkage composites was comparable to control composites but strain distribution across restoration depth differed. Marginal integrity was more compromised along the gingival than axial dentin wall.
比较可雕刻型大块充填、低收缩率和传统复合材料的应变与位移，以及沿牙本质修复界面的染料渗透情况。
制备改良II类洞（每组N = 5），分别用可雕刻型大块充填材料（3M ESPE公司的Filtek Bulk Fill Posterior；义获嘉伟瓦登特公司的Tetric EvoCeram Bulk Fill；GC公司的纤维增强型EverX Posterior；松风公司的聚硅氧烷增强型复合树脂Beautifil Bulk）、低收缩率材料（GC公司的Kalore）、纳米混合材料（义获嘉伟瓦登特公司的Tetric EvoCeram）或微混合材料（3M ESPE公司的Filtek Z250）进行充填。采用基于两台具有1μm位移灵敏度和1600×1200像素分辨率的相机的三维数字图像相关方法（ARAMIS，GOM公司）测定应变和位移。使用另一组牙齿（每组N = 8），在体视显微镜下测量沿牙本质轴向和龈向洞壁的微渗漏情况。采用方差分析、Tukey事后检验、Pearson相关性分析和配对t检验（α = 0.05）对数据进行分析。
TEC Bulk、Filtek Bulk、Beautifil Bulk和Kalore的应变在1% - 1.5%范围内。EverX和对照复合材料的应变在1.5% - 2%之间。轴向位移在5μm至30μm之间。在4mm分层复合材料中，咬合面以下2mm处应变最小，但在2mm分层复合材料中并非如此。龈向壁的微渗漏比轴向壁更严重（p < 0.05）。轴向（r = 0.082，p = 0.821；r = -0.2，p = 0.605）或龈向（r = -0.126，p = 0.729；r = -0.278，p = 0.469）的应变/位移与微渗漏之间均未发现相关性。
可雕刻型大块充填和低收缩率复合材料的应变即体积收缩率与对照复合材料相当，但修复体深度上的应变分布不同。龈向牙本质壁的边缘完整性比轴向更易受到损害。
