Apical microleakage of AH Plus and MTA Fillapex (R) sealers in association with immediate and delayed post space preparation: a bacterial leakage study

Aim. The aim of the present study was to compare the apical microleakage of root canals obturated with AH Plus and MTA Fillapex (R) sealers. Methods. A total of 76 anterior teeth were randomly divided into 4 groups (N.= 15) and in each group 2 positive and 2 negative control teeth. All the teeth were cleaned, shaped and obturated using lateral compaction technique with gutta-percha and AH Plus (R) sealer in groups 1 and 2 and MTA Fillapex (R) sealer in groups 3 and 4. In groups 1 and 3 post spaces were prepared immediately and groups 2 and 4 were stored for 1 week at 100% relative humidity and then post spaces were prepared. The teeth were connected to a bacterial microleakage evaluation system. Each 72 hours, E. faecalis bacteria were inoculated into the coronal thirds of the root canals. The study period was 90 days and the samples were evaluated on a daily basis, Meier-Kaplan technique was used for estimation of the mean time of microleakage to occur. Log-rank test was used for comparison of microleakage. Results. Contamination occurred in positive control groups on the first day of bacterial inoculation; however, the negative control groups did not exhibit any contamination up to the end of 90-day study period. the difference was not statistically significant between two materials (P>0.05). Conclusion. There were no significant differences between AH Plus (R) and MTA Fillapex (R) sealers with the two immediate and delayed postspace preparation techniques.