Efficiency of glass ionomer cement linings in preventing microleakage under Class V composite resin restorations.

The ability of glass ionomer linings to aid in the prevention of microleakage under Class V composite resin restorations has been investigated. A conventional glass ionomer lining (Ketac-bond) and two light cured linings (Vitrabond and Timeline) were evaluated with respect to their ability to reduce microleakage. Seventy two Class V cavities were restored either by a bulk fill or incremental fill technique, and following restoration, half the teeth were thermocycled in artificial saliva. Dye penetration, using a Procion orange dye was recorded along the gingival dentine wall and at the occlusal enamel margin for all teeth. The results showed significant differences in leakage along the gingival dentine wall between the various linings under all conditions. Vitrabond produced significantly less leakage than Ketac bond which in turn produced significantly less leakage than Timeline. Significant differences in microleakage were noted between the thermocycled and non-thermocycled groups. Little or no significant differences in leakage were shown between the bulk filled and incremental filled teeth.