Effect of temperature on water sorption and solubility of dental adhesive resins

Objective tudy examined the effect of temperature on water sorption and solubility characteristics of four commercial dental adhesives. The null hypothesis tested was that temperature has no effect on the water sorption and solubility characteristics of these adhesives. s sted materials were: three-step etch-and-rinse (All-Bond 2, AB), two-step etch-and-rinse (One-Step, OS), two-step self-etch (Clearfil SE Bond, SE) and one-step self-etch (Clearfil S3 Bond, S3) adhesives. Seven resin disks (6 mm in diameter × 1 mm in thickness) were prepared from each tested material and were stored in deionized water at 23 °C, 37 °C and 55 °C. Water sorption and solubility of the resin disks were measured before and after water immersion and desiccation following two consecutive sorption and desorption cycles. The water sorption and solubility values obtained were analyzed using two-way ANOVA and Tukeyʹs multiple comparison tests. The relationships between maximum water sorption, solubility and kinetics of water diffusion with temperature were evaluated by means of Pearson correlation statistic. s ibited the highest water sorption and solubility values in the second sorption–desorption cycle at 55 °C (p < 0.001). This is followed by S3, SE and AB with no significant difference between SE and AB. Significant positive correlations were observed between maximum water sorption (r = 0.307, p < 0.01), solubility (r = 0.244, p < 0.05), water sorption (r = 0.651, p < 0.001) and desorption (r = 0.733, p < 0.001) diffusion coefficients (obtained using Fickʹs law of diffusion) with temperature in the second cycle. icance emperatures increased water sorption of simplified adhesives. Such water sorption may contribute to the failure of resin–dentin bonds.