Comparison of the sealing of different dentin bonding adhesives in root-end cavities: a bacterial leakage study

Abstract

To compare the root-end sealing of the different dentin-bonding adhesives (DBAs) in root-end cavities using a bacterial leakage system. One hundred extracted single-rooted teeth were instrumented, and root-ends were resected and ultrasonically prepared. All teeth were then randomly assigned to 6 experimental groups (n = 15) and 2 control groups (positive and negative control; n = 5) for root-end filling with iBond (Heraeus Kulzer, Hanau, Germany), G-bond (GC Co., Tokyo, Japan), Xeno III Bond (Dentsply/Caulk, Milford, DE), AdheSe Bond (Ivoclar Vivadent, Schaa, Liechenstein), Clearfil Protect Bond (Kuraray, Osaka, Japan), or Clearfil Tri-S Bond (Kuraray). All preparations were further restored with a hybrid resin composite (Renew; Bisco, Schaumburg, IL). Nail varnish was applied to all external root surfaces to the level of the resected root-ends to prevent lateral microleakage. Samples were sterilized in an ethylene oxide sterilizer for 12 h. The apical 3-4 mm of the roots were immersed in brain-heart infusion culture medium with phenol red indicator within culture chambers. The coronal access of each specimen was inoculated every 48 h with a suspension of Enterococcus faecalis. Bacterial leakage was monitored every 24 h for 4 weeks. The data obtained were analyzed using a chi-squared test, with alpha = .05 as the level for statistical significance. All positive controls leaked within 24 h; none of the negative controls leaked. Under the conditions of the study, despite some variations, there were no statistically significant differences in rate of bacterial leakage among the experimental test materials at 1-4 weeks (P > .05). The type of DBA had no influence in the bacterial leakage of the root-end fillings.