Bacterial microleakage of Cavit, IRM, TERM, and Fermit: a 21-day in vitro study.

The aim of our study was to evaluate the leakage of four cements (Cavit, IRM, TERM, and Fermit) using a two-compartment model system and Streptococcus sanguis as bacterial marker. Access cavities in premolars were filled with cement and the teeth immersed in culture medium in the model system. Half of the teeth were thermocycled on day 2. Bacterial percolation into the upper compartment was measured at regular intervals (days 2, 7, 14, and 21). Cement thickness was measured at the end of the study. In the nonthermocycled group, Cavit was more leakproof than the other cements at day 2 (p = 0.011), than TERM and IRM at day 7 (p = 0.043). Fermit was more leakproof than IRM at day 7 (p = 0.043). In the thermocycled group, Cavit was more leakproof than the other cements at day 7 (p = 0.041). Thermocycling did not significantly affect leakage. Cement thickness averaged 4.1 mm and did not significantly affect leakage. These results should be considered when using cements as temporary fillings.