Early in vitro marginal microleakage associated with different lining materials under Class II amalgam restorations

The aim of this study was to determine which dental cavity lining material exhibited least microleakage when used under amalgam. Extracted premolar teeth, prepared with Class II cavities, had one of three lining materials (cavity varnish, zinc oxide-eugenol or light-cured glass-ionomer) placed. Following restoration the teeth were immersed in eosin and sectioned. Sections were subjected to image analysis measuring the linear leakage and area of spread into coronal dentine. Percentages in relation to restoration length and the area of crown dentine were calculated. Light-cured glass-ionomer cement liner significantly (P < 0.05) reduced all aspects of the microleakage parameters studied.