Method: Adper Easy Bond (AEB), Adper Prompt L-Pop (APL), Xeno III (XE3) Xeno IV (XE4), iBond Self Etch (ISE), and iBond Total Etch (ITE) samples were prepared and polymerized according to the supplier’s instructions with a Light-Emitting Diode unit (Ultradent- 750 mW). The samples (n=3) were analyzed by XPS (Kratos Axis, vacuum of 2x10-9 torr, an x-ray gun emission set to 15 mA, and an x-ray gun anode HT set to 15 kV, which equates to a power setting of 225 W). XPS surveys and high-resolution scans were taken from the external layer (depth = 0nm, (D0)) and a sub-surface layer (depth = 10nm, (D10)) after removing the external surface with Argon etching. Carbon (C1s) (at 285 eV) and Oxygen (O1s) peaks were used to compare the deconvolution of the peaks.
Result: 1) XPS survey: Statistically significant differences (p<0.05) of C1s and O1s percentages were found between D0 and D10 for all adhesives. Also, at D0: C1s for AEB and APL (80.85±0.91; 61.95±1.31), O1s for XE3 and XE4 (27.5±0.72; 7.75±1.2), and for ISE and ITE (11.89±0.42; 3.93±0.34) showed significant differences. 2) XPS high resolution: All adhesives displayed contributions from carbon impurities for C1s at 285 eV at D0, but not at D10.
Conclusion: All adhesives in this study showed that their atomic compositions in the external layer were not uniform, and their compositions, in the thickness probed, varied with depth from the surface.