Assessing fluoride concentration uniformity and fluoride release from three varnishes.
BACKGROUND
The authors investigated the fluoride content uniformity of three commercial fluoride varnishes, as well as their fluoride-release behaviors.


METHODS
The authors examined 20 doses from each of two tubes of Duraphat (Colgate-Palmolive Co., New York) and Duraflor (Pharmascience Inc., Montreal), and 20 doses of individually packaged 0.25-milliliter and 0.40-mL units of CavityShield (OMNII Oral Pharmaceuticals, West Palm Beach, Fla.). Part of the dose was dissolved in chloroform, followed by fluoride extraction with distilled water. The authors painted the remaining varnish from five predetermined doses from each group onto plastic substrates for examination of fluoride release. Fluoride concentrations in the solutions were measured with a fluoride-selective ion electrode.


RESULTS
One-way analysis of variance showed statistically significant differences between varnish groups. The fluoride content was more uniform in Duraphat and CavityShield than it was in Duraflor. The fluoride release profiles in terms of percentage of total fluoride released over time were different among different groups of varnishes and were similar among samples from the same test group. The authors found that Duraflor released consistently more fluoride in artificial saliva than did the other two varnishes.


CONCLUSIONS
Fluoride content can vary between doses dispensed from the same tube. Uniformity also varies between different varnishes and affects the retention of fluoride in the varnish.


CONCLUSIONS
Clinicians should be aware that the nonuniform appearance of fluoride varnish as squeezed out of the tube could indicate separation of ingredients, resulting in variation of fluoride content.
Shen
Chiayi
C
University of Florida, College of Dentistry, Department of Dental Biomaterials, Gainesville 32610-0446, USA. cshen@dental.ufl.edu
Autio-Gold
Jaana
J
D000704:Analysis of Variance; D002327:Cariostatic Agents / Q000032:analysis* / Q000737:chemistry; D002725:Chloroform / Q000737:chemistry; D003736:Dental Cavity Lining; D005459:Fluorides / Q000032:analysis* / Q000737:chemistry; D005460:Fluorides, Topical / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D017736:Ion-Selective Electrodes; D008422:Materials Testing; D012464:Saliva, Artificial / Q000737:chemistry; D012969:Sodium Fluoride / Q000032:analysis / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013223:Statistics as Topic; D013997:Time Factors
D002327:Cariostatic Agents; C120870:Duraflor; D005460:Fluorides, Topical; D012464:Saliva, Artificial; D012997:Solvents; C454339:cavity shield; C023807:sodium fluoride topical preparation; D002725:Chloroform; D012969:Sodium Fluoride; D005459:Fluorides