<p>This study compared the quality and efficiency&#xa0;of three obturation techniques for simulated 3D-printed C-shaped canals filled with an epoxy resin–based sealer.&#xa0;A mandibular molar with a C-shaped root canal (C1 configuration) was prepared to size #30/0.04, and 30 replicas were 3D-printed. The canals were obturated with AH Plus Jet sealer using cold lateral compaction (CLC), warm vertical compaction (WVC), or warm vertical hybrid compaction (HC) (n = 10). Cross-sections at the apical, middle, and coronal thirds were examined under a digital microscope to determine the proportions of gutta-percha, sealer, and voids. Obturation time was also recorded. Data were analyzed with one-way ANOVA and LSD post-hoc tests (α = 0.05). In the apical third, void percentages were significantly lower for CLC (1.00±0.21%) and HC (1.00±0.43%) compared with WVC (P&lt;0.001), although the effect size indicated only a modest difference (η² = 0.218). In the middle third, WVC produced the lowest void percentage (1.03 ± 0.37%; P &lt; 0.05). In the coronal third, void percentages in WVC and HC were significantly lower than in CLC (P &lt; 0.05). Among the techniques, WVC required the shortest obturation time (168.00 ± 24.29 s; P &lt; 0.001).&#xa0;Considering void percentage and treatment time, WVC appears to be the most efficient technique for obturating C-shaped canals with AH Plus Jet sealer.</p>