Marginal Adaptation of Epoxy Resin and Calcium Silicate Sealers Under Two Obturation Techniques: A Scanning Electron...

Background A fluid-tight seal at the sealer-dentin interface prevents bacterial microleakage in endodontics. This in vitro study evaluated the marginal adaptation of an epoxy resin-based sealer (AH Plus, Dentsply DeTrey GmbH, Konstanz, Germany) and a calcium silicate-based sealer (CeraSeal, Meta Biomed Co., Ltd., Cheongju, South Korea) using continuous wave compaction (CWC) and single-cone (SC) obturation across root canal thirds using scanning electron microscopy (SEM). Materials and methods Sixty extracted human maxillary central incisors were standardized to 17 mm, instrumented with ProTaper Gold (Dentsply Maillefer, Ballaigues, Switzerland) up to F3, and allocated into four groups (n = 15 each): Group I (AH Plus + CWC), Group II (AH Plus + SC), Group III (CeraSeal + CWC), and Group IV (CeraSeal + SC). After incubation at 37°C in 100% relative humidity for seven days, specimens were sectioned at 3, 6, and 9 mm from the apex. Maximum interfacial gap widths (µm) were measured under SEM (500× magnification) by a calibrated examiner blinded to group allocations. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey's post hoc tests (α = 0.05). Results Interfacial gap widths differed significantly across groups and canal thirds (p < 0.001). In the apical third, Group I showed the lowest gap (0.86 ± 0.42 µm), followed by Group II (2.04 ± 0.54 µm), Group III (3.87 ± 2.33 µm), and Group IV (5.70 ± 2.43 µm). In the middle third, Groups I and III exhibited superior adaptation. In the coronal third, Group III showed the lowest gap (1.51 ± 0.21 µm), whereas Group I had the highest gap separation (7.72 ± 3.80 µm). Conclusions AH Plus with CWC achieved superior adaptation in the apical and middle thirds, whereas CeraSeal with CWC performed best coronally. Overall, CWC produced more uniform marginal adaptation than the SC technique across both sealers.