부산대학교 도서관

This study evaluated the effect of oil contamination on the tensile bond strength of three self-etching adhesives to bovine dentin. Flat dentin surfaces, finished with wet 600-grit silicon carbide paper, were prepared on the labial surfaces of bovine lower incisor teeth. A 4-mm-diameter bonding area was demarcated on each prepared surface with adhesive tape. Before bonding, specimens were contaminated with handpiece oil for 2 seconds, left undisturbed for 10 seconds, and then washed with water spray for 5 seconds. Three self-etching adhesives, Clearfil Mega Bond, Clearfil TriS Bond ND (Kuraray Medical) and G-Bond Plus (GC), were applied and cured according to the manufacturers’ instructions. A thin layer of a light-cure type composite resin was applied and cured for 40 seconds. Then, a stainless-steel rod was cemented on the composite resin with a resin cement. The tensile bond strength test was conducted at a cross-head speed of 1.0 mm/min after 24-hour immersion in tap water at 37 °C. Meanwhile, in the control groups, oil contamination was not performed before bonding. Each group consisted of 10 specimens. Although all adhesives showed lower tensile bond strength after oil contamination, there were no statistical differences between the experimental group and the control group for each material. Failure mode analysis showed a significant difference between the control and oil contamination groups of Clearfil Mega Bond, with regard to area percentage of dentin cohesive failure and interfacial failure. The results of this study suggested that oil contamination might negatively affect the bond performance of self-etching adhesives to dentin.