The Effect of Blood Decontamination Procedures on Bond Strength to Etched Dentin

Objectives: The blood contamination may still occur during bonding procedure. This study evaluated the influence of blood contamination on shear bond strength to etched dentin and find an effective decontamination to re-establish the original bond strength for 3-step etch-and rinse, 2-step etch-and-rinse adhesives, and universal adhesives.
Methods: Seventy-five human third molars were embedded, sectioned 3 mm above DEJ using a low diamond saw. The specimens were prepared with 600-grit sandpaper, etched, rinsed, blot dried. These were contaminated with fresh human blood except for control group and randomly divided into three groups: 3-step etch-and-rinse (Optioned FL, Kerr), 2-step etch-and-rinse adhesive (Prime & Bond One Select, Dentsply), and universal adhesive (Scotchbond Universal, 3M/ESPE).
The adhesive systems were used under 5 procedures of blood decontamination:
● Group 1 (control): no contamination and adhesive applied.
● Group 2 (wiping): blood contaminating, wiping with gauze, and adhesive applied.
● Group 3 (rinsing with water): blood contaminating, rinsed, and adhesive applied.
● Group 4 (re-etching): blood contaminating, rinsed, re-etched, and adhesive applied.
● Group 5 (rinsing with ethanol): blood contaminating, rinsed with 95% ethanol, and adhesive applied.
Composite (Filtek Z350, 3M/ESPE) buildup was produced according to ISO 29022 documented testing shear bond strength. All specimens were stored for 24 hours in 37°C distilled water. The shear bond strengths were measured using a universal testing machine. Data was analyzed with one-way ANOVA and Tukey’s post hoc test.
Results: For Prime & Bond One Select, groups 2 and 5 revealed significantly lower bond strengths than groups 1 and 3 (p > 0.05). Scotchbond Universal has significantly higher bond strength than the others regardless of decontamination procedure (p < 0.05).
Conclusions: Based on the results, the bond strength to etched dentin surface contaminated with blood was restored by rinsing with water or re-etching the surface for Prime & Bond One Select. Scotchbond Universal had higher bond strength to the surface than Optibond FL and Prime & Bond One Select.