EFFECT OF DENTIN REWETTING PROTOCOLS ON THE ADHESION OF BIOCERAMIC SEALERS: A PUSH-OUT BOND STRENGTH STUDY

Abstract

Background: Bioceramic sealers are hydrophilic materials whose adhesion to root canal dentin may be influenced by the moisture condition of the canal before obturation. Dentin rewetting protocols have been proposed to optimize moisture levels and improve sealer performance.

Aim:  the effect of different dentin rewetting protocols on the push-out bond strength of a bioceramic root canal sealer.

Materials and Methods: One hundred extracted human single-rooted teeth were instrumented and randomly allocated into five groups (n = 20): Group I (dry dentin control), Group II (distilled water), Group III (normal saline), Group IV (phosphate-buffered saline [PBS]), and Group V (calcium hydroxide-saturated solution). Following rewetting, canals were obturated using a bioceramic sealer and single-cone gutta-percha technique. After storage at 37°C and 100% humidity for 7 days, root sections were subjected to push-out bond strength testing using a universal testing machine. Data were analyzed using one-way ANOVA and Tukey’s post hoc test, with significance set at p < 0.05.

Results: A statistically significant difference in push-out bond strength was observed among the groups (p < 0.001). The PBS group exhibited the highest mean bond strength (8.34 ± 0.92 MPa), followed by the calcium hydroxide-saturated solution group (7.51 ± 0.88 MPa), saline group (6.78 ± 0.79 MPa), distilled water group (6.15 ± 0.83 MPa), and control group (4.82 ± 0.71 MPa). Failure mode analysis revealed a predominance of mixed failures in the PBS group and adhesive failures in the control group.

Conclusion: Dentin rewetting significantly enhanced the adhesion of the bioceramic sealer to root canal dentin. Among the tested protocols, phosphate-buffered saline produced the highest push-out bond strength and the most favorable failure pattern. Appropriate moisture management before obturation may improve the clinical performance of bioceramic sealers.