Durability of Siloxane-bond between Ceramic and Resin Cement after Water-storage

目的：分析消除机械滞留对镜面陶瓷与树脂水泥微拉伸粘结强度的影响，研究酸性磷酸单体活化硅烷偶联剂对硅氧烷键的耐久性。方法：用长石瓷（Super porcelain AAA, Noritake）制备陶瓷样品（约7 × 7 × 10mm），用金刚石化合物抛光获得镜面。超声波清洗后，表面用硅烷偶联剂（PORCELAIN BOND ACTIVATOR, Kuraray）处理，该偶联剂由酸性磷酸盐单体（MEGA BOND PRIMER, Kuraray）活化。用4-META/MMA-TBB树脂水泥（Super-Bond, Sun Medical）在37℃空气中粘合至少24 h，然后将粘合后的试件切成平均横截面积为1.070.12mm2的梁。将它们浸泡在37℃的水中（第一组）或空气中（C…More control）。在0（基线）、1、2、4和8周后，以1mm/min的十字速度进行微拉伸粘结强度测试。用pH=2.4的酸性溶液活化的硅烷偶联剂（第二组）代替酸性单体和硅烷偶联剂单独进行同样的实验（第三组）。结果：平均基线强度约为26 MPa，所有空气储存的样品在所有老化时间下的强度相似。在水中保存的样品强度趋于降低，但由于硅氧烷键的水解，在8周内没有明显的减弱。多元线性回归分析表明，浸泡在水中的试件粘结强度显著低于空气中（p<0.05），而老化过程中粘结强度没有显著降低。各组衰老时间差异无统计学意义（p < 0.05）。另一方面，与1和2组相比，3组的结合强度显著降低，p值小于0.01。结论：在目前体外研究的限制下，可以得出结论，4-META/MMA-TBB树脂水泥与长石瓷之间硅氧烷键的耐久性来源于硅烷偶联剂的酸化作用。少

Objective : To analyze micro-tensile bond strength between resin cement and a ceramic with a mirror finished surface that eliminated the effect of mechanical retention on the bond strength, and to investigate the durability of siloxane-bonds formed by an acidic phosphate monomer activated silane coupling agent.Methods : Ceramic specimen (approximately 7 x 7 x 10mm) was prepared from feldspathic porcelain (Super Porcelain AAA, Noritake), and was polished to obtain a mirror finished surface with diamond compounds. After an ultrasonic cleaning, the surface was treated by a silane coupling agent (PORCELAIN BOND ACTIVATOR, Kuraray) activated with an acidic phosphate monomer (MEGA BOND PRIMER, Kuraray). Two silanated specimens were bonded each other using 4-META/MMA-TBB resin cement (Super-Bond, Sun Medical) at 37℃ in air for at least 24 h. Then the bonded specimen was sliced into beams with a mean cross-sectional area of 1.070.12mm2. They were immersed in water (Group 1) or stored in air (C … More ontrol) at 37℃. After 0 (baseline),1,2,4 and 8 weeks, they were subjected to micro-tensile bond strength tests at a crosshead speed of 1mm/min. The same experiment was also performed using the silane coupling agent activated with an acidic solution of pH=2.4 (Group 2) instead of the acidic monomer and the silane coupling agent alone (Group 3).Results : The average baseline strength was about 26 MPa and all air-stored specimens gave similar strengths for all aging durations. The specimens stored in water tended to give lower strengths but there was no pronounced weakening due to the hydrolysis of siloxane bond up to 8 weeks. Multiple linear regression analysis revealed that the bond strength is significantly lower in specimens immersed in water than those stored in air (p<0.05), while the bond strength was not significantly decreased during aging. Moreover, there was no significant difference between Group 1 and Group 2 for all aging durations. On the other hand, Group 3 gave significantly lower bond strength compared to Groups 1 and 2, with a p-value less than 0.01.Conclusions : Within the limitation of the present in vitro study, it can be concluded that the durability of siloxane-bond between 4-META/MMA-TBB resin cement and feldspathic porcelain is derived from the acidification of the silane coupling agent. Less