Alavi Shiva, Shirani Farzaneh, Zarei Zahra, Raji Seyed Amir Hossein
Department of Orthodontics, Dental Research Center, Dental Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Operative Dentistry, Dental Materials Research Center, Dental Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran.
Dent Res J (Isfahan). 2021 Feb 23;18:9. eCollection 2021.
This study was conducted to compare the shear bond strength (SBS) of orthodontic brackets to amalgam surfaces by two surface treatment methods, two different adhesives, and one intermediate resin and also to evaluate surface roughness after two preparation methods as well as bond failure mode.
In this study forty-eight amalgam samples were randomly allocated to four groups. In Groups 1-3, specimens were sandblasted with 50 μm aluminum oxide, followed by application of Alloy primer in Groups 1 and 2. In Group 3 Alloy primer had not used. In Group 4, samples were prepared by silica coating using a silane coupling agent. Surface roughness analysis was performed in 10 additional samples after two surface treatments. The brackets in Group 1 were bonded with Transbond XT and those in other groups were bonded with Panavia V5. All specimens were examined for SBS following 5000 times thermocycling at 5°C-50°C. Modified adhesive remnant index was utilized for the bond failure mode. Data analysis was done by one-way analysis of variance, Tukey, Kruskal-Walli and Mann-Whitney U tests. Statistical significance was set at < 0.05.
The findings indicated the mean SBS were low (ranged from 0.19 to 4.66 MPa) and significantly lower in Group 3 than in Group 4 ( = 0.009). Bond failure occurred in adhesive/amalgam interface in nearly all samples. Silica coating produced significantly lower roughness than sandblast ( = 0.009).
Silica coating had a significant higher bond strength than sandblast without application of Alloy primer. However compared to sandblast with Alloy primer, silica coating did not significantly improve the bond strength. Chemical bond between PanaviaV5 and sandblasted amalgam was not considerable.
本研究旨在通过两种表面处理方法、两种不同的粘合剂和一种中间树脂来比较正畸托槽与汞合金表面的剪切粘结强度（SBS），并评估两种制备方法后的表面粗糙度以及粘结失败模式。
在本研究中，48个汞合金样本被随机分为四组。在第1 - 3组中，样本先用50μm氧化铝喷砂处理，然后第1组和第2组应用合金底漆。第3组未使用合金底漆。第4组样本采用硅烷偶联剂进行二氧化硅涂层处理。在两种表面处理后，对另外10个样本进行表面粗糙度分析。第1组的托槽用Transbond XT粘结，其他组的托槽用Panavia V5粘结。所有样本在5°C - 50°C下进行5000次热循环后检测其SBS。采用改良的粘结剂残留指数评估粘结失败模式。数据分析采用单因素方差分析、Tukey检验、Kruskal - Walli检验和Mann - Whitney U检验。设定统计学显著性水平为<0.05。
结果表明，平均SBS较低（范围为0.19至4.66MPa），第3组显著低于第4组（=0.009）。几乎所有样本的粘结失败都发生在粘结剂/汞合金界面。二氧化硅涂层产生的粗糙度明显低于喷砂处理（=0.009）。
在不应用合金底漆的情况下，二氧化硅涂层的粘结强度显著高于喷砂处理。然而，与使用合金底漆的喷砂处理相比，二氧化硅涂层并未显著提高粘结强度。PanaviaV5与喷砂处理后的汞合金之间的化学键作用不显著。
