Noncontact Remineralization of Incipient Lesions Treated with a 5% Sodium Fluoride Varnish In Vitro
Robert L. Karlinsey, Allen C. Mackey, Lauren E. Dodge and Craig S. Schwandt
Journal of Dentistry for Children - April 2014
Purpose: Fluoride varnishes are appealing topical fluoride preparations that may provide anticaries benefits. The purpose of this in vitro study was to assess the noncontact remineralization effects of a commercial 5% sodium fluoride varnish on white spot lesions (WSLs).
Methods: Three-millimeter diameter enamel cores were extracted from bovine teeth, mounted in acrylic rods, ground and polished, and initially demineralized to create WSLs. Specimens were evaluated for surface microhardness and divided (N=6) into two groups (water control or noncontact 5% sodium fluoride white varnish with tricalcium phosphate, where one 0.50 ml unit dose was applied to acrylic rods instead of directly on WSLs). Groups were cycled in a three-day regimen consisting of two rounds of one-hour treatments and one-hour static immersions in demineralization solution. Between these events, WSLs were immersed in artificial saliva. Remineralization was evaluated using surface and cross-sectional microhardness and high-resolution scanning electron microscopy (SEM).
Results: The noncontact varnish treatment produced significantly greater percent surface microhardness recoveries (P<.05) and smaller subsurface lesions compared to the control group (P<.05). SEM revealed comparatively greater WSL porosity reduction for noncontact varnish.
Conclusions: Noncontact application of a commercial 5% sodium fluoride varnish reduced white spot lesion porosity and produced significant acid-resistant white spot lesion remineralization.