Abstract
PURPOSE: This study compared the quality of different filling techniques with two different sizes of isthmuses. MATERIALS AND METHODS: Specimens were produced with a 3D printer (EnvisionTEC Vida, Gladbeck, Germany) and allocated into groups (n=10): Group 1; narrow isthmus with cold lateral compaction (CLC), Group 2; narrow isthmus with warm vertical compaction (WVC), Group 3; wide isthmus with CLC, and Group 4; wide isthmus with WVC. The specimens were sectioned at 4 mm and 8 mm from the apex, and the filling materials and voids in the isthmuses were assessed using ImageJ software (National Institutes of Health, Bethesda, MD, USA). RESULTS: None of the techniques produced void-free fillings. In wide isthmuses, warm vertical compaction (WVC) resulted in significantly greater total void percentages (10.39 ± 8.23%) compared to cold lateral compaction (CLC) (1.30 ± 2.90%) (p = 0.000). In narrow isthmuses, both techniques produced similar void percentages (WVC: 3.33 ± 4.91%, CLC: 1.19 ± 2.67%) (p > 0.05). In the coronal portion of the wide isthmus, the amount of gutta-percha was significantly greater in WVC (p = 0.032), whereas in the apical portion, the sealer percentage was significantly higher in the CLC group. Similarly, in the narrow isthmus groups, the apical sealer percentage was greater in the CLC group (p = 0.000). CONCLUSION: Both CLC and WVC failed to produce void-free canal fillings in band-shaped isthmuses. WVC showed a higher total void percentage in wide isthmuses, whereas both techniques had similar void percentages in narrow isthmuses.