Color stability of ionomer and resin composite restoratives

This study compared the color stability of a conventional glass ionomer (Ke tac-Fil), a light polymerized resin-modified glass ionomer (PhotacFil), a p olyacid-modified resin composite or compomer (Dyract) and a microfilled res in composite (Silux Plus). Thirty-two specimens (n=8/material) were fabrica ted and stored in artificial saliva at 37 degreesC for seven weeks. A color imetric evaluation, according to the CIE L*a*b* system, was performed at 24 hours (baseline) and at the end of each week. Color difference values (Del taE*ab) were calculated. The conventional glass ionomer, resin-modified ion omer and compomer materials underwent significant color changes over time ( p<0.01). Those materials darkened and showed color shifts in both the red-g reen and yellow-blue axes.