An in vitro comparison of microleakage of restorative materials in the pulp chambers of human molar teeth.

Ninety-six human molars were accessed. After flattening of the occlusal surface and removal of the apical two-thirds of the roots, the remaining canal space was instrumented by conventional methods. The teeth were divided into six groups of 15 teeth with three positive and three negative controls. The six experimental groups were based on the material used to restore the pulp chamber and remaining canal space: 1, gutta-percha with sealer; 2, amalgam; 3, IRM; 4, light-cured posterior composite; 5, chemical-cured core paste; and 6, light-cured glass ionomer. After placement of the restorative material, the teeth were thermocycled and evaluated for microleakage using 2% methylene blue dye and incremental sectioning. The amalgam and glass ionomer groups showed significantly less leakage than the other materials. The composite, core paste, and IRM did not differ significantly from one another. The gutta-percha with sealer group showed significantly greater leakage than all other groups.