Comparison of Apical Sealing of Two Canal Sealers between Immediate Versus Delayed Post Space Preparation

The effect of post space preparation on the sealing ability of a root canal filling is important because the sealer is crucial for preserving the apical seal. The question of how, when, and how much of the gutta-percha should be removed is a debate when preparing a post space. This study is aimed to compare the effect of immediate versus delayed post space preparation on the apical seal using AH Plus and EndoREZ sealers. Forty four single rooted teeth were prepared using the step-back technique and were obturated with combinations of gutta-percha/AH Plus and gutta-percha/EndoREZ using the lateral compaction technique. Four teeth were used as positive/negative controls. After the teeth were divided randomly into six groups, post spaces were prepared either immediately after filling or after storage of the obturated teeth in saline at 37°C for one week. The post space preparation procedure was performed using hot pluggers or Gates Glidden drills leaving a 5 mm of root canal filling in the apical part. Leakage was determined by a computerized fluidfiltration device. Immediate and delayed post space preparation of the gutta-percha/AH Plus groups had mean leakage values of 4.97 µl.cmH2O.min-1.10-4 and 4.94 µl.cmH2O.min-1.10-4, respectively. The respective mean leakage values of immediate and delayed post space preparation of the gutta-percha/EndoREZ groups were 4.97 µl.cmH2O.min-1.10-4 and 5.57 µl.cmH2O.min-1.10-4. The mean leakage value obtained in the positive control group was 398.16 µl.cmH2O.min-1.10-4, whereas there was no fluid filtration in the negative control group. Better sealing was achieved in the guttapercha/AH Plus delayed group in comparison to the other groups. Delayed post space preparation in the gutta-percha/EndoREZ group showed the highest percentage of leakage.