Cumerlato Marina, Lima Eduardo Martinelli de, Osorio Leandro Berni, Mota Eduardo Gonçalves, Menezes Luciane Macedo de, Rizzatto Susana Maria Deon
Pontifícia Universidade Católica do Rio Grande do Sul, Faculdade de Odontologia (Porto Alegre/RS, Brasil).
Pontifícia Universidade Católica do Rio Grande do Sul, Faculdade de Odontologia, Disciplina de Ortodontia (Porto Alegre/RS, Brasil).
Dental Press J Orthod. 2017 Jul-Aug;22(4):47-52. doi: 10.1590/2177-6709.22.4.047-052.oar.
: The aim of this in vitro study was to evaluate and compare the effects of grinding, drilling, sandblasting, and ageing prefabricated teeth (PfT) on the shear bond strength (SBS) of orthodontic brackets, as well as the effects of surface treatments on the adhesive remnant index (ARI).
: One-hundred-ninety-two PfT were divided into four groups (n = 48): Group 1, no surface treatment was done; Group 2, grinding was performed with a cylindrical diamond bur; Group 3, two drillings were done with a spherical diamond bur; Group 4, sandblasting was performed with 50-µm aluminum oxide. Before the experiment, half of the samples stayed immersed in distilled water at 37oC for 90 days. Brackets were bonded with Transbond XT and shear strength tests were carried out using a universal testing machine. SBS were compared by surface treatment and by ageing with two-way ANOVA, followed by Tukey's test. ARI scores were compared between surface treatments with Kruskal-Wallis test followed by Dunn's test.
: Surface treatments on PfT enhanced SBS of brackets (p< 0.01), result not observed with ageing (p= 0.45). Groups II, III, and IV showed higher SBS and greater ARI than the Group 1 (p< 0.05). SBS was greater in the groups 3 and 4 (drilling, sandblasting) than in the Group 2 (grinding) (p< 0.05). SBS and ARI showed a positive correlation (Spearman's R2= 0.57; p< 0.05).
: Surface treatment on PfT enhanced SBS of brackets, however ageing did not show any relevance. Sandblasting and drilling showed greater SBS than grinding. There was a positive correlation between SBS and ARI.
本体外研究旨在评估和比较打磨、钻孔、喷砂以及老化对预成牙（PfT）正畸托槽剪切粘结强度（SBS）的影响，以及表面处理对粘结剂残留指数（ARI）的影响。
192颗PfT被分为四组（n = 48）：第1组，未进行表面处理；第2组，用圆柱形金刚石车针进行打磨；第3组，用球形金刚石车针进行两次钻孔；第4组，用50μm氧化铝进行喷砂。实验前，一半样本在37℃蒸馏水中浸泡90天。使用Transbond XT粘结托槽，并使用万能试验机进行剪切强度测试。通过表面处理和老化，采用双向方差分析比较SBS，随后进行Tukey检验。采用Kruskal-Wallis检验和Dunn检验比较表面处理之间的ARI评分。
PfT的表面处理提高了托槽的SBS（p < 0.01），老化未观察到这种结果（p = 0.45）。第2、3和4组的SBS和ARI高于第1组（p < 0.05）。第3和4组（钻孔、喷砂）的SBS高于第2组（打磨）（p < 0.05）。SBS和ARI呈正相关（Spearman's R2 = 0.57；p < 0.05）。
PfT的表面处理提高了托槽的SBS，但老化没有显示出任何相关性。喷砂和钻孔的SBS高于打磨。SBS和ARI之间存在正相关。
