The Effect Of Salivary Contamination On The Bond Strength Of Universal Adhesives

Objective The aim of this study was to investigate the effectiveness of three universal adhesives,there moist-sensibility about the saliva contamination.And decontamination effectiveness of decontamination procedures for salivary contamination before and after curing.Materials and Methods One hundred and fifty extracted teeth were trimmed by exposing the labial dentin surface and embedded in cylindrical molds.Three universal adhesives were used.Singlebond Universal(3M ESPE,St.Paul.,MN,USA),All-Bond Universal(Bisco,Inc.,Schaumburg,IL,USA),Futurabond U(Voco Gmb H,Cuxhaven,Germany).The teeth were randomly divided into groups according to universal adhesives,fifty teeth per group.The teeth were subdivided into five groups :control,saliva contamination before curing,saliva contamination after curing,saliva contamination before curing and decontamination with rinsing,drying,and adhesive,saliva contamination after curing and decontamination with rinsing,drying,and adhesive.The adhesive was applied according to the manufacture's instruction.With the exception of the control groups,the adhesive surface was contaminated with saliva for 10 sec.Using a cylindrical plastic tube 3mm long and with an inner diameter of 3mm.The tube was filled in two increments with composite resin(Filtek? Z350XT)and placed on the pretreated dentin surface.Each increment was cured with an LED curind light for 40 seconds.The prepared specimens were stored in deionized water at 37? for 24 hours.The shear bond strength was tested using a universal testing machine with a crosshead speed of 0.5mm/min.Failure modes were evaluated using an optical microscope and classified as adhesive failure,mixed failure or cohesive failure.The data were analyzed using One-way ANOVA and Fisher's Least Significant Difference test.The level for statistical significance was set at P<0.05.Statistical analysis was performed using SPSS for Windows version 20.0.Results Despite the salivary contamination occurs before or after the light cure,there is no difference between the contamination groups and the control group for the three universal adhesives.For Singlebond Universal,salivary contamination occurs after the light cure,drying the contaminated surface can improve the shear bond strength significantly.For All-Bond Universal adhesives,salivary contaminated before the light cure,decontaminated by rinsing-drying-reapplied adhesive can obviously increase the shear bond strength.For Futurabond U adhesive,salivary contamination occurs after the light cure,decontaminated by rinsing-drying-reapplied adhesive can increase the shear bond strength significantly.Conclusion Salivary contamination occurs before or after the light cure has no effect on the shear bond strength of the three universal adhesives.For Singlebond Universal,salivary contamination occurs after the light cure,drying the contaminated surface is sufficient.For All-Bond Universal adhesives,salivary contaminated before the light cure,drying the contamination surface can recover the shear bond strength as the level of control group,but decontaminated by rinsing-drying-reapplied adhesive can obviously increase the shear bond strength.For Futurabond U adhesive,salivary contamination occurs before or after the light cured will not effect the shear bond strength,when saliva contaminate after light cure,decontaminated by rinsing-drying-reapplied adhesive can increase the shear bond strength significantly.