Fluoride release from and tensile bond strength of Ketac-Fil and Ketac-Silver to enamel and dentin.

Abstract

Abstract Silver-reinforced glass ionomer cements have recently become commercially available. The purpose of this study was to determine the fluoride (F) release from, and the tensile bond strength (TBS) of Ketac-Fil, a conventional, and Ketac-Silver, a silver-reinforced glass ionomer cement, to enamel and dentin, respectively. To determine F release, 6 discs, 20 mm in diameter and 1.5 mm thick, were prepared from each material, and suspended in 50 ml glass distilled water for 24 h. The discs were washed with 50 ml TISAB and the fluoride concentrations determined electrometrically. These procedures were repeated for 14 consecutive days. The TBS of Ketac-Fil to enamel (A) and dentin (B) and of Ketac-Silver to enamel (C) and dentin (D), respectively, were determined. Fifteen test specimens were prepared with each procedure. The test specimens were stored in water at 37°C for 24 h. The test specimens were then mounted in an Instron machine and subjected to a tensile load at a cross-head speed of 0.02 inch. min −1 . The bond strengths were calculated and expressed in MN.m −2 . The data were analyzed by ANOVA and Duncan's multiple range test at the 5% level of significance. Ketac-Fil only released significantly more F (μg F. mm−2 during the first 7 days than Ketac-Silver. The following tensile bond strengths (MN.m −2 ) were obtained: A: 2.3±1.6; B: 2.0 ±2.3; C: 1.2±1.7; D: 0.5±1.3. The bond strengths of D were significantly lower than those of A and B but not significantly different from C. The addition of silver to a glass ionomer cement reduced the fluoride release and the bond strength to dentin.