The effects of different final irrigation regimens on the bond strength of sealers to root canal walls / 实用口腔医学杂志

ABSTRACT

Objective:To evaluate the bond strength of root canal sealer AH Plus and GuttaFlow to root canal walls after final rinse with 4 different final irrigation regimens.Methods:60 teeth with single-canal were prepared chemomechanically using 5.25% sodi-um hypochlorite (NaOCl)as root canal irrigant.The teeth were then randomly distributed into 3 groups(n =20)according to the final irrigation protocol1 7% EDTA followed by 2% chlorhexidine(CHX)(group 1 ),5.25% NaOCl followed by 1 7% EDTA(group 2), 0.9% normal saline(NS)(group 3).The root canals were then filled with sealers using a lentulo spiral and each group was distribu-ted into 2 subgroups according to the sealers(n =1 0)a.AH Plus;b.GuttaFlow.The roots were transversally sectioned to obtain 2mm thick dentinal slices.Then a push-out bond strength test was carried out and failure mode was observed by stereomicroscope. Results:The bond strength of AH Plus was significantly higher than that of GuttaFlow(P 0.05).When the root canals were filled with GuttaFlow,the push-out strength of group 1 ,2 and 3 was (1 .40 ±0.59)MPa, (1 .26 ±0.62)MPa and (1 .05 ±0.27)MPa respectively(P >0.05).The failure modes of AH Plus and GuttaFlow were both mainly mixed,but the proportion of adhesive failure in the canals filled with GuttaFlow were obviously higher than AH Plus.Conclusion:The bond strength to root canal wall of GuttaFlow is significantly lower than that of AH Plus.1 7% EDTA followed by 2% CHX as fi-nal irrigant can reduce the bond strength of AH Plus but has no marked effect on GuttaFlow.