New One-bottle Self-etch Adhesive is Compatible with Self-Cure Materials

Objectives: Most one-bottle self-etch adhesives are not compatible with self-cure resin cements/composites, due to their acidity (low pH) and hydrophilicity (permeability). A new Experimental Universal Adhesive (EUA, Bisco) was developed for use with both self-etch and total-etch techniques. It has low acidity and high hydrophobicity, and was designed to be compatible with self-cure materials. The purpose of this study was to test the compatibility of EUA with self-cure resin cements.

 Methods: Forty human dentins were polished by 320-grit SiC paper and rinsed with water. Twenty four of them were etched (15sec, 37%H₃PO₄) and rinsed with water. The dentin specimens were treated with EUA or One-Step (control, Bisco) according to manufacturer’s instructions. Shear bond strength (n=8) on dentin was tested using the ultradent jig method (bonding area 4.5mm²), cemented with a dual-cure resin cement (Duolink, Bisco), which was either light-cured (40sec/500mW/cm²) or dark (self)-cured (15min/37ºC), stored in de-ionized water (37ºC, 24 hours), and tested by Instron tester (crosshead speed 1mm/min). The data were analyzed statistically by one-way ANOVA and Tukey Tests (p<0.05).

 Results: The test results are shown in the table below. Means with different letters are statistically different  (p<0.05).

Adhesives	Resin Cement Curing-Mode	Shear Bond Strength, MPa (Standard Deviation)
One-Step (Control, Total-etch)	Light-Cure	33.2(6.8)a
EUA (Self-etch Technique)	Light-Cure	31.0(3.0)a
	Self-Cure	29.4(4.7)a
EUA (Total-etch Technique)	Light-Cure	33.2(7.8)a
	Self-Cure	33.7(5.6)a

 Conclusions: The bond strengths of experimental adhesive EUA (in either self-etch or total-etch technique) were not significantly different, when used with self-cured or light-cured resin composite/cements (p>0.05). EUA was compatible with self-cured resin cement (e.g. Duolink).