Diode laser irradiation increases microtensile bond strength of dentin

Laser irradiation after the immediate application of dentin bonding systems (DBSs) and prior to their polymerization has been proposed to increase bond strength. The objective of this study was to evaluate the effect of diode laser irradiation (λ = 970 nm) on simplified DBSs through microtensile bond strength tests. Forty healthy human molars were randomly distributed among four groups (n = 10) according to DBSs used [Adper™ SingleBond 2 (SB) and Adper™ EasyOne (EO)], and the respective groups were irradiated with a diode laser (SB-L and EO-L). After bonding procedures and composite resin build-ups, teeth were stored in deionized water for 7 days and then sectioned to obtain stick-shaped specimens (1.0 mm2). The microtensile test was performed at 0.5 mm/min, yielding bond strength values in MPa, which were evaluated by two-way ANOVA followed by Tukey’s test (p < 0.05) for individual comparisons. For both adhesive systems, diode laser irradiation promoted significant increases in bond strength values (SB: 33.49 ± 6.77; SB-L: 43.69 ± 8.15; EO: 19.67 ± 5.86; EO-L: 29.87 ± 6.98). These results suggest that diode laser irradiation is a promising technique for achieving better performance of adhesive systems on dentin.

已有研究表明，在即刻涂布牙本质粘接系统（dentin bonding systems, DBSs）后且于其聚合前实施激光照射，可提升粘接强度。本研究旨在通过微拉伸粘接强度测试，评估波长为970nm的二极管激光照射对简化版牙本质粘接系统的影响。选取40颗健康人类磨牙，根据所使用的牙本质粘接系统[Adper™ SingleBond 2（SB）与Adper™ EasyOne（EO）]随机分为4组（每组n=10），其中接受激光照射的两个亚组分别记为SB-L组与EO-L组。完成粘接操作与复合树脂堆塑后，将所有样本牙齿储存于去离子水中7天，随后切割制备得到截面积为1.0 mm²的棒状试样。以0.5 mm/min的加载速率开展微拉伸测试，得到以MPa为单位的粘接强度值；随后采用双因素方差分析（two-way ANOVA）结合图基（Tukey）多重比较检验进行组间两两比较，检验水准设定为p < 0.05。两种粘接系统经二极管激光照射后，粘接强度均出现统计学意义上的显著提升：SB组为33.49 ± 6.77，SB-L组为43.69 ± 8.15；EO组为19.67 ± 5.86，EO-L组为29.87 ± 6.98。上述结果表明，二极管激光照射是一种可有效提升牙本质粘接系统粘接性能的颇具应用前景的技术。