Effects of storage media on mechanical properties of adhesive systems

Purpose: To evaluate the effects of water vs. oil storage on the mechanical properties of dental adhesives over 3 and 6 months. Methods: Adhesive resin sheets were prepared by pouring either Single Bond (SB), One-Step (OS) or Clearfil Liner Bond 2V (CL) into a mold measuring 15 x 15 x 0.8 mm. After solvent evaporation, the adhesives were light-cured, removed from the mold and trimmed to either hourglass or I-beam shapes that were used to determine the true stress (TS) and modulus of elasticity (E), respectively. Control adhesive specimens were subjected to tensile testing at 0.6 mm/minute after 24 hours of immersion in distilled water. Experimental specimens were stored at 37 C in either distilled water or mineral oil and tested after 3 and 6 months. The data were analyzed by two-way ANOVA and Tukey's test. Results: Storage in water significantly decreased the TS and E of SB and OS specimens after 3 and 6 months (P 0.05). Storage in oil significantly increased the TS of the three adhesives after 3 and 6 months (P> 0.05), and the same trend was observed for E value of CL sample (P> 0.05).17210410