Machado Sissy Maria Mendes, Nascimento Diego Bruno Pinho, Silva Robson Costa, Loretto Sandro Cordeiro, Normando David
Dental Press J Orthod. 2013 May-Jun;18(3):101-6. doi: 10.1590/s2176-94512013000300016.
To evaluate in vitro the effects of tooth whitening using gel with Amorphous Calcium Phosphate (ACP) on the bond strength of metal brackets.
Thirty-six bovine incisors were sectioned at the crown-root interface, and the crowns were then placed in PVC cylinders. The specimens were divided into 3 groups (n = 12) according to whitening treatment and type of gel used, as follows: G1 (control) - no whitening; G2 - whitening with gel not containing ACP (Whiteness Perfect - FGM), G3 - whitening with gel containing ACP (Nite White ACP - Discus Dental). Groups G2 and G3 were subjected to 14 cycles of whitening followed by an interval of 15 days before the bonding of metal brackets. Shear bond strength testing was performed on a Kratos universal test machine at a speed of 0.5 mm/min. After the mechanical test, the specimens were assessed to determine the adhesive remnant index (ARI). The results were subjected to ANOVA, Tukey's test and Kruskal-Wallis test (5%).
Significant differences were noted between the groups. Control group (G1 - 11.10 MPa) showed a statistically higher shear bond strength than the groups that underwent whitening (G2 - 5.40 Mpa, G3 - 3.73 MPa), which did not differ from each other. There were no significant differences between the groups in terms of ARI.
Tooth whitening reduces the bond strength of metal brackets, whereas the presence of ACP in the whitening gel has no bearing on the results.
在体外评估使用含无定形磷酸钙（ACP）凝胶进行牙齿美白对金属托槽粘结强度的影响。
将36颗牛切牙在冠根交界处切断，然后将牙冠置于聚氯乙烯圆柱体中。根据美白处理和所用凝胶类型，将标本分为3组（n = 12），如下：G1（对照组）-未进行美白；G2 - 使用不含ACP的凝胶进行美白（皓齿美白 - FGM），G3 - 使用含ACP的凝胶进行美白（夜间美白ACP - 迪克斯牙科）。G2组和G3组在粘结金属托槽前先进行14个美白周期，然后间隔15天。在Kratos万能试验机上以0.5 mm/min的速度进行剪切粘结强度测试。力学测试后，评估标本以确定粘结剂残留指数（ARI）。结果进行方差分析（ANOVA）、Tukey检验和Kruskal-Wallis检验（5%）。
各组之间存在显著差异。对照组（G1 - 11.10 MPa）的剪切粘结强度在统计学上高于进行美白的组（G2 - 5.40 Mpa，G3 - 3.73 MPa），而G2组和G3组之间无差异。各组在ARI方面无显著差异。
牙齿美白会降低金属托槽的粘结强度，而美白凝胶中ACP的存在对结果没有影响。
