Porcelain was applied to 30 titanium and 30 Remanium CS disc-shaped frameworks in order to investigate the microleakage. Each group was divided to three subgroups each containing 10 specimens and representing the different firing cycles (10 specimens for opaque + dentine; 10 specimens for opaque + dentine + enamel; and 10 specimens for opaque + dentine + enamel porcelain + glaze application). All the specimens were stored in 37 degrees C distilled water for 2 weeks and subjected to 100 thermocycles between 5 and 55 degrees C with 30 s dwell time. The specimens were then stored in 5% basic fuchsin dye for 2 days. The washed, rinsed and air dried specimens were embedded in autopolymerizing resin and sectioned diametrically. The stereoptical investigations were performed by three independent investigators. The data were analysed by the Mann-Whitney U-test. The statistical analysis revealed that the different number of firings does not affect the amount of microleakage. However, it should be emphasized that the use of titanium would be beneficial regarding the relatively lower values obtained from the titanium-porcelain group.