Fluoride release of six restorative materials in water and pH-cycling solutions

Abstract

The fluoride release of restorative materials in deionized water has been the subject of many studies, but the behavior of these materials under conditions of acid challenge that simulates the oral cavity, needs to be further explored. Therefore, the aim of this study was to evaluate the fluoride release of restorative materials in two storage protocols: deionized water and pH- cycling system (demineralizing solution-pH 4.3 and remineralizing solution-pH 7.0) for 15 days. Eight disks of each material (Vitremer™-positive control, Dyract AP, Ariston pHc, Definite®, Tetric®Ceram and Z100-negative control) were prepared (11.0 mm x 1.5 mm) and suspended individually in 4.0 mL of each solution, which were daily changed. Daily fluoride release was analyzed with an ion specific electrode (Orion 9609) by the direct method or after HMDS-facilitated diffusion, following 1, 7 and 15 days. The values obtained were converted into μgF/mm2 and the data analyzed by ANOVA and Tukey's test (p< 0.05). The results showed that all materials released more fluoride in the pH-cycling system, except for Ariston pHc which maintained a constant release during the experiment. The highest fluoride release was presented by the positive control, Vitremer™ in pH- cycling and by Ariston pHc, in deionized water. The negative control Z100 and the resins Definite® and Tetric®Ceram did not present statistically significant differences.

Fluoride release profile of a nanofilled resin-modified glass ionomer cement

“…In fact, the most important finding is not the amount of Freleased from the material, but the Frelease pattern overtime. Accordingly, Garcez et al (13) found that the Frelease pattern from restorative materials were similar in deionized water and in solutions simulating pH-cycling.…”

“…Since the restorative materials do not have similar composition, the discussion of the results are mainly based on the comparison of the cumulative Frelease pattern rather than the Frelease differences among materials at each day. The daily Frelease mean might be influenced by several factors, such as the storage medium, being of less importance to the scientific knowledge (13).…”

A comparison of the remineralizing potential of dental restorative materials by analyzing their fluoride release profiles

“…Although they may contain fluoride in the form of the radiopaque filler ytterbium trifluoride (YbF 3 ), its release seems insufficient for remineralization. 4 Glass-ionomer cements and their derivatives should therefore be applied in all situations where tissue repair is required. 5 They owe their ability to release ions to their silicate filler content, which continuously releases and recharges fluoride, and to their structural inner porosity, which allows water to flow through the material, leading to the dissolution of the filler.…”

Fluoride Release and Rerelease After Recharging of Two Hybrid Resin Restorations in Primary Teeth. “A Comparative in Vitro Study”.

“…The addition of fluoride to restorative materials has attracted the attention of dental researchers and clinicians due to the possibility of their use as a reservoir releasing small amounts of fluoride, especially in patients with high caries risk (2). The story of the recognition and exploration of fluoride's ability to prevent caries occurrence or progression is long and interesting (3).…”