In Vitro Color Change of Immediate Versus Delayed Placement of Resin-Modified Glass Ionomer Over Silver Diammine Fluoride-Treated Teeth.

Purpose: To investigate the color difference between groups and changes over time of resin-modified glass ionomer (RMGI) restorations placed immediately after silver diammine fluoride (SDF) treatment. Methods: Thirty-six specimens were prepared from extracted human third molars, had caries artificially induced, and were divided into three groups (N equals 12): (1) control group (CG): non-SDF-treated teeth restored with RMGI; (2) group one (G1): SDF-treated teeth restored immediately with RMGI; and (3) group two (G2): SDF-treated teeth stored in saliva sub- stitute for two weeks then restored with RMGI. A Vita Easyshade ® Advance 4.0 Spectrophotometer was used to determine CIE L*a*b* values of each specimen at three different time points: (1) demineralized dentin prior to SDF application (T0); (2) following restoration (T1); and (3) two weeks following restoration (T2). The color difference ( Δ E*) and color values (L*a*b*) were analyzed within and between groups. Significance was set to P<0.05. Results: There was no significant difference in the amount of discoloration from T1 to T2 between G1 and G2, but both were significantly different from the CG (P<0.001). At T2, however, G1 had a lower, darker, average L* value(L*equals 65.27+ 1.34), which was significantly different from G2 (L*equals 69.18 + 1.39) and CG (L*equals 79.85+ 0.99; P<0.001). Furthermore, the color difference between groups at T1 and T2 was clinically detectable ( Δ E* >2.7). Conclusions: A two-week delay in in-vitro resin-modified glass ionomer restoration placement over SDF arrested carious lesions resulted in a lighter restoration; however, it did not prevent or reduce color change over time.