Yassini E, Mirzaei M, Alimi A, Rahaeifard M
Department of Operative Dentistry, Dental Research Center, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Department of Operative Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
J Mech Behav Biomed Mater. 2016 Aug;61:62-69. doi: 10.1016/j.jmbbm.2016.01.013. Epub 2016 Jan 23.
To investigate the fatigue behavior of bonding interface of lithium disilicate ceramic with three different dual cure resin cements.
Forty five bar shaped ceramic-resin-ceramic specimens were prepared and divided into 3 groups (n=15) according to the resin cement used (group1: Panavia F2.0, group 2: RelyX Ultimate, group 3: Duo-Link Universal). Three specimens of each group were tested using three point bending test and the fracture strength of the resin-ceramic bond was measured. Other specimens of each group were placed in the rotating fatigue testing machine at stresses equal to 30%, 40%, 50% and 60% of the fracture strength. The cyclic loading was continued until fracture or a maximum of 10,000 cycles. For the specimens which did not fail until 10,000 cycles, the cyclic loading was stopped and the remained fracture strength of the specimens was measured.
None of the specimens with cyclic loads of 30% and 40% of the fracture strength, have failed until 10,000 cycles. After 10,000 load cycles, the fracture strength of these specimens was significantly lower than their initial fracture strength. On the other hand, all specimens with cyclic stresses equal to 50% and 60% of the fracture strength have failed before 10,000 cycles so that the numbers of load cycles of RelyX specimens were significantly higher than those of Panavia ones and the numbers of cycles of Panavia specimens were significantly higher than those of Duo-Link specimens.
The fatigue resistance of the ceramic-resin interface is significantly lower than its bond strength. Furthermore, RelyX Ultimate showed the highest fatigue resistance and Duo-Link Universal exhibited the weakest fatigue resistance. Since dental restorations are under cyclic loading caused by mastication forces, the results of this research can be used to select fatigue resistant resin cements for bonding of ceramic restorations.
研究二硅酸锂陶瓷与三种不同双固化树脂水门汀粘结界面的疲劳行为。
制备45个棒状陶瓷 - 树脂 - 陶瓷试件，根据所用树脂水门汀分为3组（n = 15）（第1组：Panavia F2.0，第2组：RelyX Ultimate，第3组：Duo - Link Universal）。每组取3个试件进行三点弯曲试验，测量树脂 - 陶瓷粘结的断裂强度。每组的其他试件置于旋转疲劳试验机中，应力分别等于断裂强度的30%、40%、50%和60%。持续循环加载直至试件断裂或最多加载10000次循环。对于在10000次循环前未失效的试件，停止循环加载并测量试件剩余的断裂强度。
在断裂强度的30%和40%循环载荷下的试件，直至10000次循环均未失效。10000次加载循环后，这些试件的断裂强度显著低于其初始断裂强度。另一方面，所有循环应力等于断裂强度50%和60%的试件在10000次循环前均已失效，因此RelyX试件的加载循环次数显著高于Panavia试件，而Panavia试件的循环次数显著高于Duo - Link试件。
陶瓷 - 树脂界面的抗疲劳性显著低于其粘结强度。此外，RelyX Ultimate表现出最高的抗疲劳性，Duo - Link Universal表现出最弱的抗疲劳性。由于口腔修复体承受咀嚼力引起的循环载荷，本研究结果可用于选择用于陶瓷修复体粘结的抗疲劳树脂水门汀。
