Coronal microleakage assessed by polymicrobial markers

Studies have shown significant bacterial leakage following exposure of sealed root canals to artificial and natural saliva. The objective of this study was to determine contamination via bacterial migration in artificial saliva in endodontically treated teeth using different obturation techniques and sealers. A total of 144 extracted, human mandibular anterior teeth were cleaned and shaped to a #40 master apical file using hand and rotary instrumentation. One hundred and twenty teeth were divided into two experimental groups. The teeth in Group 1 were obturated with gutta-percha using lateral compaction and five different sealers, and the teeth in Group 2 were obturated with gutta-percha using thermomechanical compaction and five different sealers. The remaining 24 teeth were prepared as positive and negative controls. All specimens, except the negative controls, were inoculated every five days with Anaerobic streptococci (NCTC 9891) related to Peptostreptococcus micros and Prevotella intermedia (ATCC 25611). The contamination onset time was continuously recorded and turbid broths cultured for bacteria identification. The controls behaved as expected. Regardless of the combination between obturation techniques and different sealers, all broths became turbid during this experiment. The correlation between the obturation techniques and the sealers revealed statistical significance using ANOVA (p<0.0001), followed by the Duncan Multiple Range Test, which determined the ranking between these interactions. The combination of MicroSeal obturation technique with Ketac-Endo sealer allowed a slower rate of coronal-apical bacterial migration.