Nagura Y, Tsujimoto A, Fischer N G, Baruth A G, Barkmeier W W, Takamizawa T, Latta M A, Miyazaki M
Oper Dent. 2019 Jan/Feb;44(1):42-53. doi: 10.2341/17-261-L. Epub 2018 Jun 1.
: The purpose of this study was to evaluate the effect of reduced application times of universal adhesives on enamel bond fatigue and surface morphology of the treated enamel with constant force atomic force microscopy (AFM).
: Four universal adhesives-Adhese Universal (AU), Clearfil Universal Bond Quick (CU), G-Premio Bond (GP), and Scotchbond Universal Adhesive (SU)-were evaluated in a laboratory for their ability to adhesively bond resin composite to enamel. Shear bond strengths were initially determined using 15 specimens per test group for each adhesive. Shear fatigue strengths were then determined using 20 specimens per test group for each the adhesives. The fatigue specimens were loaded using a sine wave at a frequency of 20 Hz for 50,000 cycles or until failure occurred. AFM observations, surface Ra roughness measurements, and geometric surface area evaluations of enamel surface treated with the adhesive agents were also conducted.
: A strong relationship was found between the initial shear bond strength and shear fatigue strength for enamel surface Ra roughness but not for geometric surface area. The initial shear bond strength and shear fatigue strength of CU and GP were not influenced by different application times, unlike those of AU and SU. While the surface area of enamel treated with the adhesive agents was not significantly influenced by different application times and type of adhesive, surface Ra roughness of the enamel in the AU and SU groups significantly increased with increasing application time, unlike CU and GP.
: The results of this study suggest that universal adhesives, used with reduced application times, have adequate Ra surface roughness to provide sufficient resistance to enamel bond fatigue at application times from <1 second to 20 seconds, while the geometric surface area of adhesive-treated enamel did not show any significant changes at these different application times.
本研究旨在通过恒力原子力显微镜（AFM）评估通用型粘结剂减少涂抹次数对牙釉质粘结疲劳及处理后牙釉质表面形态的影响。
在实验室中评估四种通用型粘结剂——Adhese Universal（AU）、Clearfil Universal Bond Quick（CU）、G-Premio Bond（GP）和Scotchbond Universal Adhesive（SU）将树脂复合材料粘结至牙釉质的能力。每个测试组每种粘结剂最初使用15个样本测定剪切粘结强度。然后每个测试组每种粘结剂使用20个样本测定剪切疲劳强度。疲劳样本以20Hz的频率加载正弦波50000次循环或直至发生破坏。还对用粘结剂处理的牙釉质表面进行了AFM观察、表面粗糙度Ra测量以及几何表面积评估。
发现牙釉质表面粗糙度Ra的初始剪切粘结强度与剪切疲劳强度之间存在密切关系，但与几何表面积无关。与AU和SU不同，CU和GP的初始剪切粘结强度和剪切疲劳强度不受不同涂抹次数的影响。虽然用粘结剂处理的牙釉质表面积不受不同涂抹次数和粘结剂类型的显著影响，但与CU和GP不同，AU和SU组牙釉质的表面粗糙度Ra随涂抹次数增加而显著增加。
本研究结果表明，通用型粘结剂在减少涂抹次数使用时，在<1秒至20秒的涂抹时间内具有足够的表面粗糙度Ra，以提供足够的抗牙釉质粘结疲劳能力，而在这些不同涂抹时间下，粘结剂处理的牙釉质几何表面积未显示任何显著变化。
