Comparison of apical leakage between immediate versus delayed post-space preparation in root canals filled with AH Plus and MTA-based root canal sealers

Abstract

The success of root canal therapy depends on the ability to establish and maintain an apical seal. The aim of this study was to compare the effect of immediate versus delayed root canal preparation for post-space on apical seal using 2 types of sealers AH Plus and MTA Fillapex. Materials and Methods:This experimental study was conducted on 76 anterior teeth. All teeth were randomly divided into 4 groups. There were 2 positive and 2 negative control teeth aside from 15 experimental teeth in each group. After cleaning and shaping, root canals were filled with GuttaPercha, using lateral condensation method and AH Plus sealer(in groups 1 and 2), and MTA Fillapex sealer(in groups 3 and 4). Post-spaces were immediately prepared in groups 1 and 3, leaving the last 5 mm of GuttaPercha in root canals. The root canals in groups 2 and 4 were kept in 100% moisture for a week and post-spaces were prepared. The teeth were attached to bacterial leakage assay system. Enterococcus faecalis was placed every 72 hours into the root canal of the teeth. Duration of study was 90 days and the specimens were examined daily. The KaplanEMeier method was used to estimate the mean time of microleakage. Log-Rank testing was used to compare the survival curves. Results:The positive controls exhibited bacterial leakage after 1 day of inoculation, whereas no leakage was observed for the negative controls over the entire 90-day period. Although the mean time of microleakage in AH Plus sealerwasmore than MTA Fillapex sealer in either immediate or delayed post space preparation,this difference was not statistically significant (P-value=0.197). Conclusion:No significant difference was detected between AH Plus and MTA Fillapex sealers in either immediate or delayed post space preparation