Effect of Root Canal Drying Methods on Bioceramic Sealer Bond Strength.

Abstract

<h4>Aim</h4>This study evaluated the effects of paper point drying, microsuction, and 70% isopropyl alcohol on the push-out bond strength and interfacial adaptation of a premixed bioceramic sealer.<h4>Materials and methods</h4>Thirty extracted maxillary central incisors were prepared using NiTi rotary instruments and irrigated with NaOCl and EDTA. Specimens were randomly assigned to three groups (n = 10): paper point drying, microsuction, or 70% isopropyl alcohol. All canals were obturated with a calcium silicate-based bioceramic sealer using the single-cone technique. After one week of incubation, root slices from the coronal, middle, and apical thirds (n = 90) were subjected to push-out bond strength testing. Failure modes were evaluated stereomicroscopically, and selected specimens underwent scanning electron microscopy (SEM) analysis. Statistical analysis was performed using nonparametric tests (α = 0.05).<h4>Results</h4>The drying protocol significantly affected bond strength (p < 0.001). The isopropyl alcohol (3.23 MPa) and paper point (2.97 MPa) groups demonstrated significantly higher bond strength than the microsuction group (1.23 MPa). Apical slices showed higher bond strength than coronal and middle slices. Mixed failures predominated, while cohesive failures were more frequent in the alcohol and paper point groups. SEM revealed improved sealer-dentin adaptation with fewer interfacial gaps in these groups.<h4>Conclusions</h4>Bioceramic sealer adhesion is strongly influenced by the drying method. Paper point drying and isopropyl alcohol enhance bond strength and interfacial adaptation, whereas microsuction results in inferior performance.