Sigemori Ricardo Massao, Reis André Figueiredo, Giannini Marcelo, Paulillo Luís Alexandre M S
Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, Brazil.
Oper Dent. 2005 Mar-Apr;30(2):185-9.
The degree of conversion of resin-based luting agents used for retention of prefabricated posts has been questioned due to the difficulty of light penetration into the resin-filled root canal. This study evaluated the depth of cure of a resin-modified glass ionomer cement (Rely X--3M ESPE) and two resin-based luting agents (Rely X ARC--3M ESPE and Enforce-Dentsply). Twenty-four 14x2x2mm3 specimens were prepared in a Teflon split mold with the three luting agents (n=8). After preparation, the specimens were stored at 37 degrees C in a dark box for 24 hours prior to microhardness testing. Measurements of Knoop hardness were performed at three different depths: superficial, medium and deep thirds. The results (KHN) were statistically analyzed by repeated measures ANOVA and Tukey test (0.05), which showed that resin-based luting agents presented the highest Knoop hardness values within the superficial third. Within the medium third, there were no significant differences among luting materials. However, within the deep third, Rely X presented the highest values. KHN values of resin-based luting agents decreased remarkably as depth increased.
由于光难以穿透充满树脂的根管，用于固定预制桩的树脂类粘结剂的固化程度受到质疑。本研究评估了一种树脂改性玻璃离子水门汀（Rely X - 3M ESPE）和两种树脂类粘结剂（Rely X ARC - 3M ESPE和Enforce - Dentsply）的固化深度。使用三种粘结剂（n = 8）在聚四氟乙烯分体模具中制备了24个14x2x2mm³的样本。制备后，在进行显微硬度测试前，将样本在37摄氏度的暗箱中储存24小时。在三个不同深度进行努氏硬度测量：表层、中层和深层。结果（KHN）通过重复测量方差分析和Tukey检验（0.05）进行统计分析，结果表明树脂类粘结剂在表层三分之一处呈现出最高的努氏硬度值。在中层三分之一处，粘结材料之间没有显著差异。然而，在深层三分之一处，Rely X呈现出最高值。树脂类粘结剂的KHN值随着深度增加而显著降低。
