Elshazly Tarek M, Bourauel Christoph, Sherief Dalia I, El-Korashy Dalia I
Oral Technology, School of Dentistry, University of Bonn, 53111 Bonn, Germany.
Biomaterials Department, Faculty of Dentistry, Ain Shams University, 11566 Cairo, Egypt.
Dent J (Basel). 2020 Jul 17;8(3):76. doi: 10.3390/dj8030076.
This study compared two resin composites with similar filler systems and different matrix compositions. The depth of cure (DoC), polymerization shrinkage, and marginal leakage were evaluated. A Filtek Bulk Fill resin composite (FB) and a Filtek Supreme resin composite (FS) were used. For the DoC and polymerization shrinkage, cylindrical specimens with different thicknesses were prepared. The DoC was attributed to the bottom/top ratios of Vickers microhardness numbers. For polymerization shrinkage, each specimen was firstly scanned using micro-computed tomography (µCT) then cured for 20 s, then for 10 s, and then for 10 s, and they were rescanned between each curing time. Data were processed using the Mimics software. For marginal leakage, standardized 5 mm cavities were prepared in 90 molars. After etching and bonding, materials were packed according to groups: FB-bulk, FB-incremental, and FS-incremental, which were cured for 20, 30, and 40 s, respectively. After thermo-cycling, teeth were stored in 1% methylene blue dye for 24 h and then sectioned and observed for dye penetration. The results showed insignificant differences in the shrinkage and leakage between the different packing techniques and curing times of both materials. In conclusion, the introduction of a novel matrix into resin composite composition enabled bulk-filling in one layer up to 5 mm deep while keeping a tolerable polymerization shrinkage.
本研究比较了两种具有相似填料体系和不同基体组成的树脂复合材料。评估了固化深度（DoC）、聚合收缩率和边缘微渗漏情况。使用了一种Filtek Bulk Fill树脂复合材料（FB）和一种Filtek Supreme树脂复合材料（FS）。对于固化深度和聚合收缩率，制备了不同厚度的圆柱形试件。固化深度通过维氏显微硬度值的底部/顶部比率来确定。对于聚合收缩率，每个试件首先使用微型计算机断层扫描（µCT）进行扫描，然后固化20秒，接着固化10秒，再固化10秒，并且在每次固化时间之间重新进行扫描。数据使用Mimics软件进行处理。对于边缘微渗漏，在90颗磨牙中制备标准化的5毫米洞型。酸蚀和粘结后，按照分组填充材料：FB - 整块填充、FB - 分层填充和FS - 分层填充，分别固化20、30和40秒。热循环后，将牙齿保存在1%的亚甲蓝染料中24小时，然后切片并观察染料渗透情况。结果表明，两种材料在不同填充技术和固化时间下的收缩率和微渗漏情况差异不显著。总之，在树脂复合材料组成中引入新型基体能够实现单层高达5毫米深度的整块填充，同时保持可耐受的聚合收缩率。
