IADR Abstract Archives
Standard Method to Assess the Minimum Fluoride Release From F-Varnishes
Objectives: Working groups for ISO and ANSI/ADA standards for fluoride releasing varnishes are currently considering methods for assessing that every fluoride varnish contains at least a minimum amount of fluoride that is soluble and releasable to the oral environment. It is known that different brands of F-varnishes release very little to much more fluoride to the oral environment, yet many have been shown to have clinical efficacy. The purpose of this project was to develop a pass/fail test for the assessment of a minimum amount of fluoride to be released.
Methods: The end of 6.4mm diameter plastic rods were painted with F-varnish product, suspended in 20mL DI-H2O and stirred for 1-h at room temperature. A 5mL aliquot of the solution is mixed with 5mL of TISAB-II and analyzed for fluoride content with a calibrated fluoride ion-selective electrode (F-ISE). Twelve commercially available products, three 0-F varnish negative controls, and 3 experimental low-F varnish candidates with either 1% or 2.5% NaF were tested. Varnish mass applied was measured for each sample. All products were tested in triplicate. The pass/fail point was chosen to be the linear detection limit of a F-ISE at 0.02 ppmNaF (1.1x10-6 mol/L ).
Results: All commercial products passed, the negative controls failed, the experimental low-fluoride varnished passed this minimum test. The mass of varnish applied did not correlate with the amount of F released (r2=0.0127, p>0.1). We noted that it was vital that the sample be well mixed prior to application to the plastic rod. The surface area that receives the F-varnish must be constant and near 30mm2.
Conclusions: This pass/fail test is designed to assure that all F-varnish products have some amount of soluble fluoride. This method may be applicable for establishing a standard minimum amount of fluoride to be released by commercially available F-varnishes.
Methods: The end of 6.4mm diameter plastic rods were painted with F-varnish product, suspended in 20mL DI-H2O and stirred for 1-h at room temperature. A 5mL aliquot of the solution is mixed with 5mL of TISAB-II and analyzed for fluoride content with a calibrated fluoride ion-selective electrode (F-ISE). Twelve commercially available products, three 0-F varnish negative controls, and 3 experimental low-F varnish candidates with either 1% or 2.5% NaF were tested. Varnish mass applied was measured for each sample. All products were tested in triplicate. The pass/fail point was chosen to be the linear detection limit of a F-ISE at 0.02 ppmNaF (1.1x10-6 mol/L ).
Results: All commercial products passed, the negative controls failed, the experimental low-fluoride varnished passed this minimum test. The mass of varnish applied did not correlate with the amount of F released (r2=0.0127, p>0.1). We noted that it was vital that the sample be well mixed prior to application to the plastic rod. The surface area that receives the F-varnish must be constant and near 30mm2.
Conclusions: This pass/fail test is designed to assure that all F-varnish products have some amount of soluble fluoride. This method may be applicable for establishing a standard minimum amount of fluoride to be released by commercially available F-varnishes.