Effect of Blood Contamination with 1-step Self-etching Adhesives on Microtensile Bond Strength to Dentin

Abstract

This study evaluated the effect of blood contamination and decontamination methods on the microtensile bond strength of 1-step self-etching adhesive systems to dentin contaminated after adhesive application and light curing. Three commercially available "all-in-one" adhesives (One Up Bond F, Xeno III and Adper Prompt L-Pop) and 1 resin composite (Clearfil AP-X) were used. Third molars that had been stored in distilled water with 0.5% thymol at 4 degrees C were ground with #600 SiC paper under running water to produce a standardized smear layer. The specimens were randomly divided into groups according to the 3 adhesive systems. The adhesive systems were used under 3 conditions: no contamination, which was the control (C); contamination of the light-cured adhesive surface with blood and reapplication of adhesive (Contamination 1) and contamination of the light-cured adhesive surface with blood, then washing, drying and reapplication of the adhesive (Contamination 2). Following light curing of the adhesive, the resin composite was placed in 3 increments up to a 5-mm-thick layer on the bonded surface. All specimens were stored in distilled water at 37 degrees C for 24 hours. The microtensile bond strength was measured using a universal testing machine (EZ test), and data were analyzed by 1-way ANOVA followed by the Duncan test to make comparisons among the groups (p=0.05). After debonding, 5 specimens were selected from each group and examined in a scanning electron microscope to evaluate the modes of fracture. For all adhesives, contamination groups showed lower bond strength than the control (p<0.05). There was no statistically significant difference among the control groups (p>0.05). For Xeno III and Adper Prompt L-Pop, contamination group #2 showed the lowest bond strength among the groups (p<0.05). For One Up Bond F, contamination group #2 showed higher bond strength than contamination group #1 but showed no statistical significance between them (p>0.05).

Influence of Different Rubber Dam Application on Intraoral Temperature and Relative Humidity

“…In actual dental practice, however, moisture is more commonly excluded by simply using cotton rolls. This method might also prevent contamination by saliva or blood on the adhered surfaces of both direct and indirect bonded restorations 1,6,18) . However, the present results revealed that the relative humidity of the operating field was significantly higher than that of the indoor environment.…”

“…Since then, caries treatment in the molar region has shifted from indirect metal restoration and amalgam filling to direct bonding restoration using composite resin. However, the humidity of the oral environment makes high in vitro adhesion difficult to achieve 1,6,18) . Contamination of the adhered surface by saliva or blood may also inhibit bonding 3,5,9,11,13,17) .…”

Influence of Ankaferd Blood Stopper on shear bond strength of bonding systems

“…When rubber dam isolations are not used, contamination of the operating field with saliva or blood is a frequent problem 20) . Saliva and blood contamination may also create a thin film on the dentin surface that hinders adhesive penetration into the dentinal tubules 21) .…”

“…Although a short application time reduces the risk of blood contamination in the field of operation, it may sometimes be impossible to maintain a dry operative field. In the total-etching system, gingival bleeding can occur after rinsing off the phosphoric acid gel, coincidentally coming into contact with cavosurface margins 1,2,20) . In vitro shear bond strength testing is commonly used to quantitatively analyze and rank the performance of adhesive systems on enamel and dentin 26,27) .…”

Influence of handpiece maintenance sprays on resin bonding to dentin

“…As already mentioned, contamination of blood or saliva significantly reduces the bond strength 12,13 due to the inhibition of resin penetration. In order to prevent cavity surfaces produced by such contaminants, dentists typically use the rubber dam isolation technique, which is useful for creating a suitable environment for resin bonding since it not only isolates the surface from these fluids, but also reduces intraoral humidity.…”