Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil.
Department of Biomaterials and Oral Biology, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.
J Mech Behav Biomed Mater. 2021 Jul;119:104529. doi: 10.1016/j.jmbbm.2021.104529. Epub 2021 Apr 21.
To evaluate the effect of three adhesive systems applied under electric current on microtensile bond strength (μTBS) and degree of conversion (DC). Molar teeth were restored with the aid of three adhesive systems (Adper Single Bond 2-SB2; Clearfil SE Bond-CSE; and Single Bond Universal-SBU) under different electric current intensities (0 μA; 25 μA; and 50 μA). Composite resin blocks were built up in increments (2 mm) and sectioned into 1 × 1 mm beams. The μTBS was tested after 24 h and 1 y distilled water storages. Samples (n = 10) from 24 h to 1 y storages were immersed in a 50% ammoniacal silver nitrate solution and submitted to scanning electron microscopy. The silver nitrate in the hybrid layer was quantified (ImageJ software). The adhesive systems' dentinal infiltration was analyzed using confocal laser scanning microscopy. Fourier transform near infrared spectroscopy was used to measure the DC. The μTBS data were submitted to two-way ANOVA (time vs. electric current) and Bonferroni's test (α = 0.05). Quantitative nanoleakage data were submitted to two-way ANOVA (electric current vs. adhesive) and Bonferroni's test (α = 0.05). DC data were submitted to one-way ANOVA and Tukey's test (α = 0.05) for each adhesive system. The electric current statistically increased the μTBS for SB2 and CSE in 24 h storage, as well as for SB2, CSE and SBU in 1 y storage. No significant difference was observed between storage time for CSE and SBU. When compared to the control, electric currents (25 μA and 50 μA) showed significantly higher DC mean values for SB2 and SBU, and had no effect on CSE. The electric currents (25 μA and 50 μA) reduced the adhesive system's nanoleakage after 1-year storage, and improved the infiltration of SB2 and CSE. Both electric current intensities improved dentinal interface stability.
为了评估在电流下应用的三种粘接系统对微拉伸粘接强度（μTBS）和转化率（DC）的影响。利用三种粘接系统（Adper Single Bond 2-SB2；Clearfil SE Bond-CSE；和Single Bond Universal-SBU）在不同电流强度（0 μA；25 μA；和 50 μA）下辅助磨牙修复。复合树脂块以增量（2 mm）构建，并切成 1×1 mm 梁。在 24 小时和 1 年蒸馏水储存后测试 μTBS。从 24 小时到 1 年储存的样品（n = 10）浸入 50%氨化硝酸银溶液中，并进行扫描电子显微镜检查。使用 ImageJ 软件对混合层中的硝酸银进行定量。使用共焦激光扫描显微镜分析粘接系统的牙本质渗透。傅里叶变换近红外光谱用于测量 DC。将 μTBS 数据提交给双向方差分析（时间对电流）和 Bonferroni 检验（α=0.05）。定量纳米渗漏数据提交给双向方差分析（电流对粘接）和 Bonferroni 检验（α=0.05）。对于每个粘接系统，DC 数据均提交给单向方差分析和 Tukey 检验（α=0.05）。电流在 24 小时储存时显著增加了 SB2 和 CSE 的 μTBS，在 1 年储存时也增加了 SB2、CSE 和 SBU 的 μTBS。CSE 和 SBU 的储存时间之间没有观察到显著差异。与对照组相比，电流（25 μA 和 50 μA）对 SB2 和 SBU 的 DC 平均值显示出显著更高的值，对 CSE 没有影响。电流（25 μA 和 50 μA）降低了 1 年后粘接系统的纳米渗漏，并改善了 SB2 和 CSE 的渗透。两种电流强度均提高了牙本质界面的稳定性。
