Soares Fabio Zovico Maxnuck, Rocha Rachel de Oliveira, Raggio Daniela Prócida, Sadek Fernanda Tranchesi, Cardoso Paulo Eduardo Capel
Department of Dental Materials, University of São Paulo, São Paulo, Brazil.
Pediatr Dent. 2005 Nov-Dec;27(6):457-62.
The aims of this in vitro study were to: (1) compare bond strength of different adhesive systems to primary and permanent dentin using microtensile test; and (2) evaluate the interaction of these materials to primary and permanent dentin by means of scanning electron microscopy (SEM).
Middle-coronal dentin surfaces of 18 exfoliated primary and 18 extracted permanent molars were exposed and teeth were randomly divided, according to their adhesive system, into 3 groups (N=6 per group): (1) Clearfil SE Bond (SE); (2) One Up Bond F (OU); and (3) Single Bond (SB). Then, 5-mm high composite blocks were constructed. After bonding procedures, the teeth were stored in distilled water at 37 degrees C for 24 hours prior to the specimens' preparation. For the microtensile test, teeth (N=5 per group) were longitudinally sectioned into 2 axes rendering beam-specimens that were glued to special devices, which were mounted in a Universal Testing Machine to be loaded under a crosshead speed of 1 mm/min until fracture. One tooth of each group was prepared for SEM.
Microtensile bond strength mean values (MPa) to primary/permanent dentin were: (1) SE=60.0/61.4; (2) OU=54.5/53.3; and (3) SB=70.1/64.9. Two-way analysis of variance (ANOVA) showed no significant differences (P>.05) for the bond strength values among primary and permanent dentin groups, neither among groups SExSB and SExOU. SEM images of SE and SB showed a well-defined, uniform, and continuous hybrid layer. A continuous hybrid layer, however, was not found for OU.
Bond strength and micromorphologic characteristics of the adhesive systems evaluated were not influenced by the substrate. OU achieved worse results.
本体外研究的目的是：（1）使用微拉伸试验比较不同粘结系统与乳牙和恒牙牙本质的粘结强度；（2）通过扫描电子显微镜（SEM）评估这些材料与乳牙和恒牙牙本质的相互作用。
暴露18颗脱落乳牙和18颗拔除恒牙的中冠部牙本质表面，根据粘结系统将牙齿随机分为3组（每组n = 6）：（1）Clearfil SE Bond（SE）；（2）One Up Bond F（OU）；（3）Single Bond（SB）。然后，构建5毫米高的复合树脂块。粘结程序完成后，在制备标本前，将牙齿在37℃蒸馏水中保存24小时。对于微拉伸试验，将牙齿（每组n = 5）纵向切成两个轴，制成梁状标本，粘贴到特殊装置上，安装在万能试验机上，以1毫米/分钟的十字头速度加载直至断裂。每组制备一颗牙齿用于SEM观察。
与乳牙/恒牙牙本质的微拉伸粘结强度平均值（MPa）为：（1）SE = 60.0/61.4；（2）OU = 54.5/53.3；（3）SB = 70.1/64.9。双向方差分析（ANOVA）显示，乳牙和恒牙牙本质组之间的粘结强度值以及SE×SB组和SE×OU组之间均无显著差异（P>0. .05）。SE和SB的SEM图像显示出清晰、均匀且连续的混合层。然而，未发现OU有连续的混合层。
所评估的粘结系统的粘结强度和微观形态特征不受底物的影响。OU的结果较差。
