Analysis of the effects of apical backfilling depth on apical sealing of different root canal filling qualities and morphologies.

ABSTRACT

PURPOSE: The aim of this study was to evaluate the effects of apical backfilling depth on the apical sealing of different root canal filling qualities and morphologies. METHODS: 3D-printed root canals (A round, B oval, C long oval, D flat) were used and divided into subgroups by root canal filling quality (a good, b poor, c nonfilling) and backfilling depth (3 mm, 5 mm). A glucose microleakage device was used to measure leakage. RESULTS: (1) 3-mm iRoot BP Plus was filled at the apex, and no obvious leakage occurred in the good root canal filling group, which was significantly smaller than that in the poor/nonfilling groups (P < 0.05). Under good root canal filling conditions in groups A, B, C, and D, no obvious leakage was observed. Under poor/nonfilling root canal filling conditions, there was significant leakage; A and B (P > 0.05) and C and D were compared (P < 0.05). (2) Apical backfilling with 5-mm iRoot BP Plus showed no significant leakage in the poor root canal filling groups with the four morphologies. CONCLUSION: 3-mm iRoot BP Plus was filled at the apex, root canal filling was poor, apical sealing was poor, and root canal morphology affected apical sealing. Apical backfilling with 5-mm iRoot BP Plus improved apical sealing under poor root canal filling conditions, and apical sealing was unaffected by root canal morphology.