The effect of different final irrigation regimens on the dentin tubule penetration of various root canal sealers: A confocal laser scanning microscopic study in vitro

The purpose of this study is to evaluate the effects of different final irrigation regimens on tubuler penetration of root canal sealers; AH Plus, EndoRez, Tech BioSealer Endo into dentinal tubules using confocal laser scanning microscope. One hundred and sixty recently extracted human mandibular premolar teeth with single canals were used. After chemomechanic preparation using Ni-Ti hand instruments with 5,25% sodium hypochlorite (NaOCl) irrigation, all teeth were irrigated with 5ml 5,25% NaOCl and 2,5ml distilled water then the samples were divided into 5 groups (n=32) according to the final irrigation solution used. G1: 5ml %17 EDTA + 2,5ml DW, G2: 5ml %17 EDTA + 2,5ml DW + 2,5ml %2 CHX, G3: 5ml %7 MA + 2,5ml DW, G4: 5ml %7 MA + 2,5ml DW + 2,5ml %2 CHX, G5: 5ml %5,25 NaOCl + 2,5ml DW. Before obturation, two roots from each group (total of 10 roots) were left unobturated to examine under scanning electron microscopy to analyse smear layer removal. The groups were subgrouped randomly into 3 groups (n=10) for obturation with root canal sealers; AH Plus (Dentsply Maillefer, Ballaigues, Switzerland), EndoREZ (Ultradent, Inc, South Jordan, UT, USA), Tech BioSealer Endo (Isasan, Rovello Porro, Italy) labeled with fluorescent dye. The teeth were sectioned at distances of 2, 6, and 10 mm from the root apex. Total percentage and maximum depth of sealer penetration were measured using confocal laser scanning microscopy. AH Plus showed the greatest tubule penetration while Tech BioSealer Endo showed the least. Chlorhexidine irrigation did not negatively effect sealer penetration except group G4A and made a positive effect on the tubule penetration of other sealers examined.