Nondestructive Inspection of Resinous Restorations using an X-ray Micro focus CT Scanner

在牛牙本质上制备直径为4×2 mm的圆柱形洞，分别用复合树脂和树脂改性玻璃离子充填。将光固化树脂复合物（Clearfil APX，色调A2，批号0664 AA，Kuraray，Osaka）和树脂改性的玻璃离聚物（Fuji Iceland Type II LC，色调A2，批号0664 AA，Fuji Iceland Type II LC，色调A2，批号0664 AA，Kuraray，Osaka）置于反应器中。粉末081132，液体271031，GC，东京）被选为填充材料。根据制造商的建议，将它们填充到空腔中并固化。在填充复合材料之前，根据制造商的建议完成粘合过程，即，复合材料填充物（Clearfil Mega Bond，批号011239，Kuraray，Osaka）的底漆和粘合以及玻璃离聚物填充物的调节（牙本质调节剂批号261031，GC，Tokyo）。每种材料制备三个样本。将样品浸入蒸馏水中，直到水被平衡吸收或在干燥器中用硅胶干燥2周。然后，使用X射线微焦点CT扫描仪（MCT-CB 100 MF，Hitachi Medico，Tokyo）观察样品。在干燥条件下，可以显示出结晶内部的缺陷，例如气泡和裂纹，并且可以区分出腔壁和凝固材料之间宽度约15微米的间隙。X线微焦点CT扫描仪似乎是有用的质量控制和改进的修复过程中，特别是对修复材料。

Experimental cylindrical cavities were prepared in bovine dentin(Φ4×2 mm) and filled with a composite resin and a resin modified glass ionomer. A light-cured resin composite (Clearfil APX, shade A2, Lot.0664AA, Kuraray, Osaka) and a resin modified glass ionomer (Fuji Ionomer Type II LC, shade A2, Lot. Powder 081132,liquid 271031,GC, Tokyo) were selected as filling materials. They were filled into the cavities and cured according to the manufacturer's recommendations. Before filling the composite, the bonding process, that is, the priming and bonding for the composite filling (Clearfil Mega Bond, Lot.011239,Kuraray, Osaka) and the conditioning (Dentin Conditioner Lot.261031,GC, Tokyo) for the glass ionomer filling were completed according to manufacturer's recommendations. Three specimens were prepared for each material. The specimens were immersed in distilled water until the water was absorbed in equilibrium or dried in a desiccator with silica gel over 2 weeks. Then, specimens were observed using an X-ray Microfocus CT Scanner (MCT-CB100MF, Hitachi Medico, Tokyo).In the dry condition defects inside the restorations such as air bubbles and cracks could be shown and gaps of about 15 microns in width between the cavity wall and the set material could be distinguished. The X-ray Microfocus CT Scanner appeared to be useful for the quality control of restorations and the improvement of the restorative process, especially for resinous materials.