Cavalcante Larissa Maria Assad, Erhardt Maria Carolina Guilherme, Bedran-de-Castro Ana Karina Barbieri, Pimenta Luiz André Freire, Ambrosano Glaucia Maria Bovi
Department of Restorative Dentistry, School of Dentistry at Piracicaba, University of Campinas, São Paulo, Brazil.
Am J Dent. 2006 Feb;19(1):37-40.
To investigate the behavior of two bonding systems: self-etching primer Clearfil Liner Bond 2V (CLB) and total-etch Single Bond (SB) when submitted to two bond strength tests: shear bond strength (SBS) and microtensile (MTBS).
Flat dentin surfaces were obtained at the facial surface of extracted bovine incisors. muTBS started with adhesive application and incremental resin composite insertion. Samples were then sliced into 1 mm slabs parallel to the long axis of the tooth. Half of the specimens from each group were trimmed in order to obtain dumbbell-shaped (D) specimens with a cross-sectional area of 1 mm2, and in the other half of the group, the slabs were cut into beams (B) with a cross section of 1 mm2 area. Specimens were individually fractured on a microtensile apparatus. For SBS, crown segments were embedded in polyester resin and a flat dentin surface was exposed for bonding. After adhesive and restorative procedures were accomplished, the specimens were kept in water for 24 hours prior to bond testing. The tests were performed in a universal testing machine. MPa values were analyzed by Tukey's test (P < 0.05), two-way ANOVA (muTBS) and Student's t-test (SBS).
Mean values (SD) on muTBS were: SB/B: 42.6 (15.1), SB/D: 35.4 (6.8), CLB/B: 14.3 (10.3) and CLB/D: 27.0 (7.9). SBS values (SD) were: SB: 17.3 (5.6) and CLB 15.9 (7.2). Beam specimens bonded with CLB presented the lowest results. SBS did not show statistical differences between groups. The results showed that the shear bond test seemed to lack the sensitivity that is required to detect subtle differences between bonding agents or procedures.
研究两种粘结系统在进行两种粘结强度测试时的表现，这两种粘结系统分别是自酸蚀底漆Clearfil Liner Bond 2V（CLB）和全酸蚀粘结剂Single Bond（SB），两种粘结强度测试分别是剪切粘结强度（SBS）和微拉伸粘结强度（MTBS）。
在拔除的牛切牙唇面制备平坦的牙本质表面。微拉伸粘结强度测试从涂布粘结剂和逐层填入树脂复合材料开始。然后将样本沿牙齿长轴切成1mm厚的薄片。每组样本的一半被修整成横截面面积为1mm²的哑铃形（D）样本，另一半切成横截面面积为1mm²的小梁（B）样本。样本在微拉伸测试仪上单独折断。对于剪切粘结强度测试，将牙冠部分嵌入聚酯树脂中，暴露出平坦的牙本质表面用于粘结。完成粘结剂和修复程序后，在进行粘结测试前将样本在水中保存24小时。测试在万能材料试验机上进行。通过Tukey检验（P<0.05）、双向方差分析（微拉伸粘结强度测试）和Student t检验（剪切粘结强度测试）对MPa值进行分析。
微拉伸粘结强度测试的平均值（标准差）为：SB/B：42.6（15.1），SB/D：35.4（6.8），CLB/B：14.3（10.3），CLB/D：27.0（7.9）。剪切粘结强度测试值（标准差）为：SB：17.3（5.6），CLB：15.9（7.2）。用CLB粘结的小梁样本结果最低。剪切粘结强度测试在各组之间未显示出统计学差异。结果表明，剪切粘结强度测试似乎缺乏检测粘结剂或操作之间细微差异所需的敏感性。
