The Effect of Calcium Hydroxide on the Bond Strength of Resilon/Epiphany Self-Etch and Assessment of Calcium Hydroxide Removal Techniques: An Ex-Vivo Study

Calcium hydroxide is the most widely used intracanal medicament in endodontics, which should be removed prior to permanent root canal filling to minimize its intervention with the bonding of endodontic sealers. This ex-vivo study aimed to evaluate the effect of pretreatment with calcium hydroxide on the bond strength of Resilon/Epiphany self etch (SE) to the radicular dentin after removing the calcium hydroxide by hand file or ultrasonic methods. Thirty-six single-rooted human extracted teeth were used in this study. After root canal preparation, the teeth were divided into three groups. In group 1, as the control, no pretreatment was performed; while in groups 2 and 3, this was carried out using calcium hydroxide paste. After one week, the paste was removed with hand stainless steel K-files in group 2 and ultrasonic instrumentation in group 3. All samples were obturated with Resilon/Epiphany SE. One-millimeter slices of mid-root dentin were prepared for the push-out test (14 slices per group). After the bond strength was assessed, the failure modes were examined. The data were analyzed using one-way ANOVA and Dunnett Post Hoc tests. Group 2 significantly showed the lowest bond strength (0.947 ± 0.47) (P = 0.01). No significant differences were found between the control group (2.32 ± 1.43) and group 3 (1.78 ± 1.04) (P = 0.01). Under the conditions of this ex vivo study, calcium hydroxide as the intracanal medicament and its removal using hand instrumentation adversely affected the bond strength of Resilon/Epiphany SE.