Leakage in roots coronally sealed with different temporary fillings

This study was aimed at determining the ability of different coronal tempor ary fillings to prevent corono-apical penetration of bacteria. A total of 1 03 human teeth, including three controls, were instrumented, obturated with gutta-percha, coronally sealed with either Cavit, Intermediate Restorative Material (IRM), glass-ionomer cement, Cavit/glass-ionomer cement, or IRM/g lass-ionomer cement, respectively. Each root was fixed with wax between two chambers: the coronal chamber harboring soy broth with 10(8) colony-formin g units of Streptococcus mutans/ml, the apical chamber containing sterile s oy broth. The latter was checked daily for turbidity, indicating corono-api cal penetration of bacteria. The Cavit group, the IRM group, and the Cavit/ glass-ionomer cement group showed significantly more leakage than the glass -ionomer cement group of the IRM/glass-ionomer cement group. If a sample le aked, all except one (IRM/glass-ionomer cement) leaked before-day 12. This in vitro study seems to indicate that only glass-ionomer cement and IRM com bined with glass-ionomer cement may prevent bacterial penetration to the pe riapex of root-filled teeth over a 1-month period.