Three Years Storage Stability of a Universal Adhesive

Objectives: Modern dental adhesives are complex formulations that combine a plurality of different chemical compounds in one bottle. Reactions or evaporation of components might potentially affect shelf life and/or bond strength. Aim of this study was to assess the shear bond strength according to ISO29022 (SBS) in self etch (SE) and total etch (TE) application modes of 3M™ Scotchbond™ Universal Plus Adhesive (SBUP, 3M) stored in its vial at room temperature (RT, 23°C) for 0, 12, 24 and 36 months.
Methods: Bovine incisors were embedded in cold-cure acrylic resin. The labial surface of each tooth was ground to expose enamel (E) or dentin (D). A cylindrical button of 3M™ Filtek™ Z250 Universal Restorative A3 (3M, 2.36mm diameter, 2mm height) was cured on the tooth surfaces treated with SBUP in SE and TE modes according to the manufacturer’s instructions, (n=6). SBS was measured according to ISO29022.
Results: The table shows the SBS in MPa. The standard deviations (SD) are given in parentheses. All data per substrate and application mode were analyzed by ANOVA and multiple comparisons using Fisher’s LSD procedure (p<0.05). Means with the same letters are statistically the same.
Conclusions: Several statistically significant differences were found. On all substrates with all application modes, high SBS of well over 25 MPa were obtained for fresh SBUP and product stored for 36 months at RT.