Analysis of a self-adhesive resin cement using immediate or delayed light curing on adhesive/root dentin interface after fiber post cementation

Abstract

Aim: To evaluate the performance of new self-adhesive resin cement (Megalink Auto, Odontomega Import) using immediate or delayed light curing on adhesive/root dentin interface after fiber post cementation. Methods: Forty human, canine roots were endodontically treated, and the post space was prepared. Specimens were randomized into four groups based on the cement and light-curing timing used (n = 10): RU-I – RelyX U200 (3M ESPE) resin cement with immediate photoactivation after fiberglass post cementation; MG-I – Megalink Auto (Odontomega Import), resin cement with immediate photoactivation after fiberglass post cementation; RU-5 – RelyX U200 (3M ESPE), resin cement with a 5-min delay light-curing timing; and MG-5 – Megalink Auto (Odontomega Import), resin cement with a 5-min delay light-curing timing. Specimens were cross-sectioned (one slice for each third: cervical, middle, and apical) and subjected to push-out and confocal laser microscopy tests. In addition, the fracture mode was analyzed using a stereomicroscope. Kruskal–Wallis tests followed by Dunn's post-test were used to analyze the data (α = 0.05). Results: There was no statistical difference in the bond strength between the groups (p <0.05), regardless of the third analysis. The most insidious failure pattern was adhesive (type 2). There was a statistical difference in the penetrability of the cementation system between the RU-I and MG-5 groups in the cervical and middle thirds (p <0.05). Conclusions: There was no influence of the light-curing time point on bond strength between the dentin and the cementation system, with greater penetrability with immediate light-curing of the self-adhesive resin cement.