Santos Catielma Nascimento, Matos Felipe de Souza, Rode Sigmar de Mello, Cesar Paulo Francisco, Nahsan Flávia Pardo Salata, Paranhos Luiz Renato
Universidade Federal de Sergipe, Programa de Pós-graduação em Odontologia (Aracaju/SE, Brazil).
Universidade Estadual Paulista, Instituto de Ciência e Tecnologia, Programa de Pós-Graduação em Odontologia Restauradora (São José dos Campos/SP, Brazil).
Dental Press J Orthod. 2018 Nov-Dec;23(6):64-72. doi: 10.1590/2177-6709.23.6.064-072.oar.
To assess the short-term effect of two in vitro erosive challenge protocols on the bond strength of metal orthodontic brackets on bovine enamel.
Sixty bovine incisors were selected and randomly divided into six groups: AS7 (artificial saliva - 7 days, Control Group); CC7 (Coca-Cola™ - 7 days); LJ7 (lime juice - 7 days); AS30 (artificial saliva - 30 days, Control Group); CC30 (Coca-Cola™ - 30 days); LJ30 (lime juice - 30 days). Microhardness testing was performed prior to the erosive challenge to verify the standardization of samples. Immersion was performed 4x/day for five minutes, for either 7 or 30 days. After immersions were concluded, the brackets were bonded and shear bond strength was assessed after 48 hours. The Adhesive Remnant Index (ARI) was also assessed. Data were analyzed by two-way ANOVA, followed by Tukey's post-hoc and Student's t test for paired samples, and the Kruskal-Wallis non-parametric test (α = 5%).
The mean and standard deviation of microhardness testing of total samples were 281.89 ± 44.51 KHN. There was no statistically significant difference in shear bond strength for the time factor (7 or 30 days; F5.54= 0.105; p = 0.901). However, there was a statistically significant difference for the solution factor (F5.54= 6.671; p = 0.003). These differences occurred among solutions of Saliva x Coca-Cola™ (p = 0.003) and Coca-Cola™ x Lime Juice (p = 0.029). The assessment of the Adhesive Remnant Index showed no significant difference between groups.
The immersion time used in the erosion protocols did not affect the bond strength of brackets to teeth. Coca-Cola™ induced significantly higher shear bond strength values than lime juice and artificial saliva. However, the short term effects of 7/30 days in this in vitro study may not be extrapolated for in vivo ones. Clinical studies should be conducted, substantiating the laboratory results.
评估两种体外侵蚀性挑战方案对金属正畸托槽与牛牙釉质粘结强度的短期影响。
选取60颗牛切牙，随机分为六组：AS7（人工唾液 - 7天，对照组）；CC7（可口可乐™ - 7天）；LJ7（柠檬汁 - 7天）；AS30（人工唾液 - 30天，对照组）；CC30（可口可乐™ - 30天）；LJ30（柠檬汁 - 30天）。在进行侵蚀性挑战之前进行显微硬度测试，以验证样本的标准化。每天浸泡4次，每次5分钟，持续7天或30天。浸泡结束后，粘结托槽，并在48小时后评估剪切粘结强度。还评估了粘结剂残留指数（ARI）。数据采用双向方差分析，随后进行Tukey事后检验和配对样本的Student t检验，以及Kruskal-Wallis非参数检验（α = 5%）。
所有样本显微硬度测试的平均值和标准差为281.89±44.51 KHN。时间因素（7天或30天）对剪切粘结强度没有统计学上的显著差异（F5.54 = 0.105；p = 0.901）。然而，溶液因素存在统计学上的显著差异（F5.54 = 6.671；p = 0.003）。这些差异出现在唾液与可口可乐™（p = 0.003）以及可口可乐™与柠檬汁（p = 0.029）的溶液之间。粘结剂残留指数的评估显示各组之间没有显著差异。
侵蚀方案中使用的浸泡时间不影响托槽与牙齿的粘结强度。可口可乐™引起的剪切粘结强度值显著高于柠檬汁和人工唾液。然而，本体外研究中7/30天的短期影响可能无法外推至体内情况。应进行临床研究以证实实验室结果。
