The aim of this study was to evaluate the effect of dentin blood
contamination during different steps of the restorative procedure on
resin cement shear bond strength to dentin. Crows of 120 bovine
incisors were prepared to obtain flat superficial dentin surfaces.
Dentin was etched with phosphoric acid and contaminated with fresh
blood for 10 seconds, before or after adhesive system application.
Different treatments were tested in contaminated dentin, resulting on
eight groups (N=15). Composite resin restorations (TPH Spectrum,
Dentsply) were adhesively fixed (Excite, Ivoclar-Vivadent) with resin
cement (Variolink 2, Ivoclar-Vivadent) and shear bond strength test
(0.5 mm/min) was performed. Morphologic observations were carried out
with scanning electron microscopy (SEM). Data (MPa) were submitted to
one-way ANOVA following Tukey’s test (p<0.05), showing that
blood contamination during adhesive procedure negatively affects bond
strength, and decontamination methods do not recover original bond
strength. The negative effects of blood contamination on shear bond
strength to dentin and resin cement were significant in all
contaminated groups; none of the tested dentin treatment procedures
resulted in higher bond strength irrespective of the moment on which
blood contamination took place
