Araújo Raíssa Costa, Bichara Lívia Monteiro, Araujo Adriana Monteiro de, Normando David
a Resident, Department of Orthodontics, Brazilian Association of Dentistry, Belém, Pará, Brazil.
b Graduate student, Department of Orthodontics, School of Dentistry, Federal University of Pará, Belém, Pará, Brazil.
Angle Orthod. 2015 Jul;85(4):673-7. doi: 10.2319/012914-80.1. Epub 2014 Sep 24.
To compare the degree of debris and friction of conventional and self-ligating orthodontic brackets before and after clinical use.
Two sets of three conventional and self-ligating brackets were bonded from the first molar to the first premolar in eight individuals, for a total of 16 sets per type of brackets. A passive segment of 0.019 × 0.025-inch stainless steel archwire was inserted into each group of brackets. Frictional force and debris level were evaluated as received and after 8 weeks of intraoral exposure. Two-way analysis of variance and Wilcoxon signed-rank test were applied at P < .05.
After the intraoral exposure, there was a significant increase of debris accumulation in both systems of brackets (P < .05). However, the self-ligating brackets showed a higher amount of debris compared with the conventional brackets. The frictional force in conventional brackets was significantly higher when compared with self-ligating brackets before clinical use (P < .001). Clinical exposure for 8 weeks provided a significant increase of friction (P < .001) on both systems. In the self-ligating system, the mean of friction increase was 0.21 N (191%), while 0.52 N (47.2%) was observed for the conventional system.
Self-ligating and conventional brackets, when exposed to the intraoral environment, showed a significant increase in frictional force during the sliding mechanics. Debris accumulation was higher for the self-ligating system.
比较传统正畸托槽和自锁正畸托槽在临床使用前后的碎屑量和摩擦力。
在8名个体中，从第一磨牙到第一前磨牙粘结两组，每组3个传统托槽和自锁托槽，每种托槽共16组。将一段0.019×0.025英寸的被动不锈钢弓丝插入每组托槽中。在收到托槽时以及口内暴露8周后评估摩擦力和碎屑水平。采用双向方差分析和Wilcoxon符号秩检验，P < 0.05。
口内暴露后，两种托槽系统中的碎屑堆积均显著增加（P < 0.05）。然而，与传统托槽相比，自锁托槽的碎屑量更高。在临床使用前，传统托槽的摩擦力显著高于自锁托槽（P < 0.001）。临床暴露8周后，两种系统的摩擦力均显著增加（P < 0.001）。在自锁系统中，摩擦力增加的平均值为0.21 N（191%），而传统系统为0.52 N（47.2%）。
自锁托槽和传统托槽在口内环境中滑动力学过程中摩擦力显著增加。自锁系统的碎屑堆积更多。
