Influence of Primekote® polymer in orthodontic bonding

Abstract Objective The Primekote® (TP) polymer was incorporated to the of Orthodontic Bracket mesh base to improve bond strength and make it more efficient. The purpose of this study was to assess the shear bond strength and adhesive remnant index (ARI) of these brackets. Material and method The test sample consisted of thirty bovine incisors divided into 2 groups: with a group with TP® brackets (n=15), and a control group with Morelli® brackets (n=15) without Primekote® technology. The TransbondTM XT was used as adhesive system in both groups, following the same protocol and manufacturer’s instructions. Specimens were stored in distilled water for 24 hours and then submitted to shear bond strength test in a universal testing machine (EMIC DL2000). The assessment of ARI was performed under stereomicroscope by two calibrated examiners. Result No significant differences (p>0.05) in shear bond strength were found between the two groups according to the independent t-test. The Wilcoxon test was used to assess ARI data and statistical difference was found between Morelli® and TP® Nu-Edge brackets; the last one left less remaining adhesive on tooth surface. Conclusion TP® brackets had higher adherence to the adhesive system as shown by lower ARI scores, but this does not improve its clinical performance.

目的：将Primekote®（TP）聚合物应用于正畸托槽网底，以提升其粘结强度并优化临床应用效率。本研究旨在评估此类托槽的剪切粘结强度（shear bond strength）与粘结残留指数（adhesive remnant index, ARI）。材料与方法：实验样本共计30颗牛切牙，分为两组：实验组为搭载Primekote®技术的TP®托槽（n=15），对照组为未应用Primekote®技术的Morelli®托槽（n=15）。两组均采用Transbond™ XT作为粘结系统，严格遵循相同操作流程及厂商指导说明书进行实验操作。所有标本经蒸馏水储存24小时后，使用万能试验机（EMIC DL2000）开展剪切粘结强度测试。由2名经过校准的检验人员在体视显微镜下完成粘结残留指数的评分工作。结果：独立样本t检验结果显示，两组间剪切粘结强度无显著性差异（p>0.05）。针对粘结残留指数数据采用Wilcoxon检验进行分析，结果显示Morelli®托槽与TP® Nu-Edge托槽间存在统计学差异，TP® Nu-Edge托槽在牙面残留的粘结剂更少。结论：TP®托槽与粘结系统的结合性能更优，表现为更低的粘结残留指数评分，但该优势并未提升其临床应用效能。