Effect of fluoride agents on the color stability of esthetic restorative materials

Objective The aim of the study was to estimate the effect of acidulated phosphate fluoride (APF) gel and fluoride varnish on the color stability of esthetic restorative materials. Methodology The materials included were glass ionomer cement, resin-modified glass ionomer cement, and composite resin. A Teflon matrix (12×2 mm) mold was used to fabricate 108 specimens from all restorative materials. Further, 36 disks of each restorative material were then randomly divided into three groups (n = 12) according to the fluoride application: deionized water (control), APF (1.23%), and fluoride varnish. Color change was measured by means of a spectrophotometer using a CIE L*a*b* (Comission International l´Eclairage) system before and 24 h after fluoride treatment. Statistical comparisons were made using first mixed model repeated measure analysis of variance on the transform ranked data under the assumption of non-normal data and to see which main or interaction effect was significant. Results In control groups, when the baseline and final readings of glagg ionomer cement, resinmodified glass ionomer cement, and composite materials were compared for color changes, similar values were observed and hence results were nonsignificant. When all materials were compared for color changes before and after the application of APF, highly significant mean differences were found among the groups. Hence, application of APF results in a highly significant color change in all materials compared with varnish application. Conclusion Topical fluoride agents – either fluoride varnish or APF gels – cause discoloration in all esthetic restorative materials. However, this discoloration is not visually perceptible.