In vitro remineralization associated with a bioerodible fluoridated resin and a fluoride varnish.

Purpose: To examine the remineralization effects of a bioerodible fluoridated resin.
Methods: 36 extracted permanent molars were suspended into an artificial caries solution to create an artificial caries-like lesion. Teeth were sectioned longitudinally to obtain 100 microm sections containing the artificial caries-like lesion, then photographed with polarized light microscopy in an imbibition media of water, representing a minimum of 5% pore volume. An acid-resistant varnish was applied to the surfaces of the sections, leaving only the natural external tooth surface and caries-like lesion exposed. The external tooth surface of 12 samples had 5% sodium fluoride varnish applied, 12 samples had 5% sodium fluoride bioerodible resin applied, and the remaining samples acted as controls. The sections were returned to the tooth, placed in an artificial saliva solution and brushed daily for 30 days. The sections were removed and photographed under polarized light as before. Using a computerized imaging system, the area of the body of the lesion was measured, comparing the same section before and after the 30-day experimental period to evaluate the remineralization process.
Results: The mean percent area remineralization (+/-SD) was: bioerodible fluoridated resin 44.1 +/- 12.1; fluoride varnish 19.1 +/- 9.2; control 2.4 +/- 3.4. ANOVA indicated a significant variance among groups (P < 0.001). Tukey's multiple comparison test demonstrated the fluoridated resin to enhance remineralization significantly greater (P < 0.001) than the fluoride varnish and control and the fluoride varnish to enhance remineralization significantly greater (P < 0.002) than the control.