Wongsamut Wittawat, Satrawaha Sirichom, Wayakanon Kornchanok
Department of Preventive Dentistry, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand.
Department of Restorative Dentistry, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand.
J Orthod Sci. 2017 Oct-Dec;6(4):129-135. doi: 10.4103/jos.JOS_25_17.
Testing of methods to enhance the shear bond strength (SBS) between orthodontic metal brackets and amalgam by sandblasting and different primers.
Three hundred samples of amalgam restorations (KerrAlloy) were prepared in self-cured acrylic blocks, polished, and divided into two groups: nonsandblasted and sandblasted. Each group was divided into five subgroups with different primers used in surface treatment methods, with a control group of bonded brackets on human mandibular incisors. Following the surface treatments, mandibular incisor brackets (Unitek) were bonded on the amalgam with adhesive resin (Transbond XT). The SBS of the samples was tested. The adhesive remnant index (ARI) and failure modes were then determined under a stereo-microscope. Two-way analysis of variance, Chi-square, and Kruskal-Wallis tests were performed to calculate the correlations between and among the SBS and ARI values, the failure modes, and surface roughness results.
There were statistically significant differences of SBS among the different adhesive primers and sandblasting methods ( < 0.05). The sandblasted amalgam with Assure Plus showed the highest SBS ( < 0.001). Samples mainly showed an ARI score = 1 and mix-mode failure. There was a statistically significant difference of surface roughness between nonsandblasted amalgam and sandblasted amalgam ( < 0.05), but no significant differences among priming agents ( > 0.05).
Using adhesive primers with sandblasting together effectively enhances the SBS between orthodontic metal brackets and amalgam. The two primers with the ingredient methacryloxydecyl dihydrogen phosphate (MDP) monomer, Alloy Primer and Assure Plus, were the most effective. Including sandblasting in the treatment is essential to achieve the bonding strength required.
通过喷砂处理和使用不同的底漆来测试增强正畸金属托槽与汞合金之间剪切粘结强度（SBS）的方法。
在自凝丙烯酸树脂块中制备300个汞合金修复体（KerrAlloy）样本，进行抛光，然后分为两组：未喷砂组和喷砂组。每组再分为五个亚组，采用不同的底漆进行表面处理，另有一组作为对照组，将托槽粘结在人类下颌切牙上。表面处理后，用粘结树脂（Transbond XT）将下颌切牙托槽（Unitek）粘结在汞合金上。测试样本的SBS。然后在立体显微镜下确定粘结剂残留指数（ARI）和失败模式。进行双向方差分析、卡方检验和克鲁斯卡尔 - 沃利斯检验，以计算SBS与ARI值、失败模式以及表面粗糙度结果之间的相关性。
不同粘结底漆和喷砂方法之间的SBS存在统计学显著差异（<0.05）。使用Assure Plus底漆进行喷砂处理的汞合金显示出最高的SBS（<0.001）。样本主要显示ARI评分为1和混合模式失败。未喷砂汞合金和喷砂汞合金之间的表面粗糙度存在统计学显著差异（<0.05），但底漆之间无显著差异（>0.05）。
喷砂处理与粘结底漆联合使用可有效提高正畸金属托槽与汞合金之间的SBS。含甲基丙烯酰氧基癸基二氢磷酸酯（MDP）单体成分的两种底漆，即合金底漆和Assure Plus，效果最为显著。在处理过程中加入喷砂处理对于达到所需的粘结强度至关重要。
