Oliveira Adauê S, Barwaldt Caroline K, Bublitz Luana S, Moraes Rafael R
School of Dentistry, Federal University of Pelotas, Rua Gonçalves Chaves 457, 96015-560, Pelotas-RS, Brazil.
J Orthod. 2014 Jun;41(2):124-7. doi: 10.1179/1465313313Y.0000000087. Epub 2014 Feb 12.
This study investigated the the influence of bracket displacement or rotation during fixation and the time of excess adhesive removal from around the bracket on bond strength to enamel.
Stainless steel brackets were bonded to the buccal faces of bovine incisors using Transbond XT® adhesive resin. The teeth were divided into five groups (n = 20). In the control group, no displacement or rotation of the bracket was carried out. In the Displac-A group, excess adhesive was removed after the bracket was displaced 2 mm incisally. In the B-Displac group, excess adhesive was removed before the bracket was displaced incisally. In the Rotat-A group, excess adhesive was removed after the bracket was rotated 45°. In the B-Rotat group, excess adhesive was removed before the bracket was rotated. Photoactivation was carried out on the lateral sides of the bracket. A shear test was conducted 10 min after fixation using a knife-edged chisel. Bond strength data were analysed using ANOVA and Fisher's test (5%). The adhesive remnant index (ARI) was scored under magnification. ARI data were analysed using the Kruskal-Wallis test (5%).
No significant differences were detected among the Control, Displac-A, Rotat-A and B-Rotat groups. The B-Displac group showed lower bond strength than all of the other groups, except Displac-A. No significant differences were observed in ARI scores across groups.
Displacements of the brackets during fixation did not seem to affect the enamel bond strength when excess adhesive is removed after the final positioning of the bracket.
本研究调查了固定过程中托槽移位或旋转以及从托槽周围去除多余黏结剂的时间对牙釉质黏结强度的影响。
使用Transbond XT®黏结树脂将不锈钢托槽黏结到牛切牙的颊面。将牙齿分为五组（n = 20）。对照组不进行托槽的移位或旋转。在Displac - A组中，托槽垂直向移位2 mm后去除多余黏结剂。在B - Displac组中，托槽垂直向移位前去除多余黏结剂。在Rotat - A组中，托槽旋转45°后去除多余黏结剂。在B - Rotat组中，托槽旋转前去除多余黏结剂。对托槽侧面进行光固化。固定10分钟后使用刃口凿进行剪切试验。使用方差分析和Fisher检验（5%）分析黏结强度数据。在放大条件下对黏结剂残留指数（ARI）进行评分。使用Kruskal - Wallis检验（5%）分析ARI数据。
对照组、Displac - A组、Rotat - A组和B - Rotat组之间未检测到显著差异。B - Displac组的黏结强度低于除Displac - A组外的所有其他组。各组间ARI评分未观察到显著差异。
当在托槽最终定位后去除多余黏结剂时，固定过程中托槽的移位似乎不会影响牙釉质黏结强度。
