Effect of coating materials on restorative glass-ionomer cement surface

Historically glass-ionomer samples have been coated with a varnish to protect the material from the effect of water on the surface. However, varnishes have been shown to peel from this surface. The set cement matrix may become chalky and can erode rapidly. Light-cured glazing agents may demonstrate the ability to limit water movement across the setting-cement surface. In this in vitro study samples were investigated colorimetrically to evaluate the effect of water contamination. Perceivable differences were not found, particularly when a coating of light-cured bonding or glazing agents was applied. We conclude that the color stability of glass-ionomer cements is enhanced with the use of a protective coating of light-cured bonding or glazing agents.