Zarif Najafi Hooman, Mousavi Mohammad, Nouri Nadia, Torkan Sepideh
Orthodontic Research Center, Department of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Department of Orthodontics, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran.
Int Orthod. 2019 Mar;17(1):80-88. doi: 10.1016/j.ortho.2019.01.009. Epub 2019 Feb 11.
There are controversies regarding the most reliable conditioning method of the aged composite surface to ensure optimum bond strength. The purpose of this study was to evaluate the shear bond strength of metal brackets to microhybrid composite restorations after different surface preparation techniques.
A total of sixty microhybrid composite samples were prepared using upper right central incisor celluloid crown as a mold. Samples were treated with 4 different surface conditioning methods: (1) etching, (2) sandblasting, (3) grinding, and (4) CO laser irradiation. Samples were then bonded with metal brackets and underwent shear bond strength testing. A scanning electron microscope was carried out and the data was analysed by one-way ANOVA and post-hoc Tukey test. Bond failure was examined by stereomicroscope and scored based on adhesive remnant index (ARI). Kruskal-Wallis test was used to compare ARI values (α=0.05).
Shear bond strength values in the sandblasting group (17.18±1.53MPa) were significantly higher than the other groups. There was no significant difference between the grinding (12.87±3.38MPa) and laser (11.08±1.37MPa) groups (P=0.09). The lowest values were recorded in the etching group (6.78±1.69MPa). There was a significant difference in ARI scores among the four groups (P<0.001). ARI scores were mostly 2 and 3 in the sandblasting and grinding group, while in the etching and laser groups ARI was mostly 0 and 1.
Surface preparation by sandblasting and CO laser provides clinically acceptable results with regards to bond strength and ARI score, however grinding and acid etching failed to produce the same results.
关于老年复合树脂表面最可靠的预处理方法以确保最佳粘结强度存在争议。本研究的目的是评估不同表面处理技术后金属托槽与微混合复合树脂修复体之间的剪切粘结强度。
使用右上中切牙赛璐珞冠作为模具制备总共60个微混合复合树脂样本。样本采用4种不同的表面预处理方法进行处理：（1）酸蚀，（2）喷砂，（3）打磨，和（4）CO激光照射。然后将样本与金属托槽粘结并进行剪切粘结强度测试。进行扫描电子显微镜观察，并通过单因素方差分析和事后Tukey检验对数据进行分析。通过体视显微镜检查粘结失败情况，并根据粘结剂残留指数（ARI）进行评分。使用Kruskal-Wallis检验比较ARI值（α=0.05）。
喷砂组的剪切粘结强度值（17.18±1.53MPa）显著高于其他组。打磨组（12.87±3.38MPa）和激光组（11.08±1.37MPa）之间无显著差异（P=0.09）。酸蚀组记录到最低值（6.78±1.69MPa）。四组之间的ARI评分存在显著差异（P<0.001）。喷砂组和打磨组的ARI评分大多为2和3，而酸蚀组和激光组的ARI大多为0和1。
喷砂和CO激光表面处理在粘结强度和ARI评分方面提供了临床上可接受的结果，然而打磨和酸蚀未能产生相同的结果。
