Baia Juliana C P, Oliveira Roberta P, Ribeiro Mara E S, Lima Rafael R, Loretto Sandro C, Silva E Souza Junior Mário H
Department of Restorative Dentistry, UFPA-Federal University of Pará, Belém 66075-110, Brazil.
Laboratory of Functional and Structural Biology, UFPA-Federal University of Pará, Belém 66075-110, Brazil.
Int J Dent. 2020 May 14;2020:2609359. doi: 10.1155/2020/2609359. eCollection 2020.
The objective of this in vitro study was to assess the influence of prolonged bleaching pre- and postrestoration on the bond strength (microshear) to enamel using 4% hydrogen peroxide (PH4). In the postrestorative bleached specimens evaluation, the composite cylinders were assembled after bleaching, while in the prebleached specimens, the cylinders were assembled before. Therefore, in the postbleached specimens, 60 bovine teeth were randomly assigned as follows: G1: control; G2: 14 days bleaching before bond strength (BS) testing; G3: 21 days; and G4: 28 days. In prebleached specimens, 180 bovine teeth were randomly assigned as follows: G1: control; G5: 14 days bleaching, storage in artificial saliva (AS) for 24 h before BS testing; G6: 14 days beaching, AS storage for 7 days before BS testing; G7: 21 days bleaching, AS storage for 24 h before BS testing; G8: 21 days bleaching, AS storage for 7 days before BS testing; G9: 28 days bleaching, AS storage for 24 hours before BS testing; and G10 : 28 days bleaching, AS storage for 7 days before BS testing. The results were submitted to ANOVA one-way (postrestoration bleaching) and two-way (prerestoration bleaching) and Tukey's post hoc test ( ≤ 0.05). In the postrestoration bleaching, no statistical difference between times was found. However, when bleached groups were compared to the control (G1), an expressive difference was detected ( ≤ 0.0001). For prerestoration bleaching, all experimental groups were statistically different from G1 ( ≤ 0.05), except G6 ( ≥ 0.01), and for G5 and G6, statistical differences were found ( ≤ 0.01). There were no significant differences between G7 and G8 and between G9 and G10, regardless of the AS storage times ( ≥ 0.05). It was concluded that prolonged bleaching with PH4 decreased adhesion resistance regardless of the moment of the bleaching (post- and prerestoration bleaching).
本体外研究的目的是评估使用4%过氧化氢（PH4）进行修复前和修复后长时间漂白对牙釉质粘结强度（微剪切力）的影响。在修复后漂白样本的评估中，复合树脂圆柱体在漂白后组装，而在预漂白样本中，圆柱体在之前组装。因此，在漂白后样本中，60颗牛牙被随机分配如下：G1：对照组；G2：在粘结强度（BS）测试前漂白14天；G3：21天；G4：28天。在预漂白样本中，180颗牛牙被随机分配如下：G1：对照组；G5：漂白14天，在BS测试前在人工唾液（AS）中储存24小时；G6：漂白14天，在BS测试前在AS中储存7天；G7：漂白21天，在BS测试前在AS中储存24小时；G8：漂白21天，在BS测试前在AS中储存7天；G9：漂白28天，在BS测试前在AS中储存24小时；G10：漂白28天，在BS测试前在AS中储存7天。结果进行单向方差分析（修复后漂白）和双向方差分析（修复前漂白）以及Tukey事后检验（≤0.05）。在修复后漂白中，未发现不同时间之间存在统计学差异。然而，当将漂白组与对照组（G1）比较时，检测到显著差异（≤0.0001）。对于修复前漂白，除G6（≥0.01）外，所有实验组与G1均存在统计学差异（≤0.05），并且对于G5和G6，发现存在统计学差异（≤0.01）。无论AS储存时间如何，G7和G8之间以及G9和G10之间均无显著差异（≥0.05）。得出的结论是，无论漂白时间（修复后和修复前漂白）如何，使用PH4长时间漂白都会降低粘结抗力。
