Effect of endodontic irrigants on microleakage of coronal restorations

To evaluate the effect of endodontic irrigants on the sealing ability of resin composite coronal restorations bonded with two different bonding systems, Clearfil SE Bond and PQ1.

The specially designed coronal preparations with distal margins on dentin and mesial margins on enamel were performed on 100 single-rooted teeth. They were initially divided into five groups. Irrigants used during the root canal preparation in each group were as follows: sodium hypochlorite, hydrogen peroxide, Tubulicid Plus, Cetrexidin and saline (control). After root canal filling, each irrigation group was divided into two bonding groups. Following the placement of the composite restorations, the specimens were immersed in India ink and cleared to allow visualization of the leakage.

The differences among the irrigation groups were statistically significant only at margins remaining on dentin structures for both of the bonding resins (P< 0.05). Sodium hypochlorite, hydrogen peroxide groups demonstrated higher leakage scores than the controls (P< 0.005). Leakage patterns of Cetrexidin and Tubulicid Plus groups did not differ significantly from the controls (P> 0.005). Cetrexidin allowed better sealing than Tubulicid Plus in PQ1 bonded restorations, but did not in Clearfil SE Bond samples.