Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
Dent Mater. 2010 Jul;26(7):659-65. doi: 10.1016/j.dental.2010.03.009. Epub 2010 Apr 20.
To assess the repair potential of resin-modified glass-ionomer cements (RMGICs) with additional RMGIC and resin composite.
Specimens of two proprietary RMGICs (Ketac N100 (Ketac Nano), 3M/ESPE, St Paul, MN; Fuji II LC, GC Corporation, Tokyo) were prepared and stored in water at 37 degrees C for 4 days. The surface of the RMGIC was finished flat with 600-grit silicon carbide paper. After treatment of the original surface by either phosphoric acid or polyacrylic acid for 20s, fresh RMGIC of the same brand was added in a plastics cylinder. Untreated specimens were used as a control. Further specimens were either left untreated (control) or etched with phosphoric acid for 20s, and resin composite added. Specimens were stored in water at 37 degrees C for 24h, and the shear bond strength measured. The fractured surfaces were examined for mode of failure. Additional RMGIC specimens were prepared for the examination of replicas of the finished and acid treated surfaces.
The bond strength of new Ketac N100 to old Ketac N100 was in the order of 1.7 MPa, irrespective of the surface treatment, and many specimens failed before testing. The bond strength of new Fuji II LC to old Fuji II LC was in the order of 10 MPa, irrespective of the surface treatment. The bond strength of resin composite bonded to both RMGICs approximated 9-16 MPa. The mode of failure of the RMGIC to RMGIC bond varied depending on the products, and the mode of failure of the resin composite to RMGIC bond was predominantly cohesive in the RMGIC. SEM examination of the RMGIC surfaces showed little effect from acid treatment.
Based on this laboratory study, repair of RMGIC with additional RMGIC maybe clinically unpredictable, depending on the products used; repair with resin composite appears to be the preferred option.
评估添加额外的树脂改良型玻璃离子水门汀（RMGIC）和树脂复合材料对 RMGIC 的修复潜力。
制备两种专利 RMGIC（Ketac N100（Ketac Nano），3M/ESPE，圣保罗，MN；Fuji II LC，GC 公司，东京）的样本，并在 37°C 的水中储存 4 天。用 600 目碳化硅砂纸将 RMGIC 的表面打磨平整。用磷酸或聚丙烯酸处理原始表面 20s 后，在塑料圆柱中添加相同品牌的新鲜 RMGIC。未处理的样本作为对照。进一步的样本要么未经处理（对照），要么用磷酸蚀刻 20s，然后添加树脂复合材料。样本在 37°C 的水中储存 24h，测量剪切粘结强度。检查断裂表面的失效模式。为了检查完成后的酸处理表面的复制品，制备了额外的 RMGIC 样本。
新 Ketac N100 与旧 Ketac N100 的粘结强度约为 1.7MPa，与表面处理无关，许多样本在测试前就失效了。新 Fuji II LC 与旧 Fuji II LC 的粘结强度约为 10MPa，与表面处理无关。树脂复合材料与两种 RMGIC 的粘结强度约为 9-16MPa。RMGIC 之间的粘结失效模式取决于产品，树脂复合材料与 RMGIC 的粘结失效模式主要是 RMGIC 内的内聚性。对 RMGIC 表面的 SEM 检查表明酸处理的影响很小。
根据这项实验室研究，取决于所使用的产品，用额外的 RMGIC 修复 RMGIC 在临床上可能是不可预测的；用树脂复合材料修复似乎是首选方案。
