title: The influence of smear layer on coronal leakage of Roth 801 and AH26 root canal sealers.
abstract: The aim of this in vitro study was to examine the effect of removal of smear layer on the coronal seal of two commonly used root canal sealers: Roth 801, a zinc oxide-eugenol-based sealer and AH26, an epoxy resin-based sealer. Ninety-six single-rooted human teeth were used. The teeth were instrumented and assigned to four experimental groups of 20 teeth each, with 10 teeth as controls and the remaining six teeth examined under a scanning electron microscope. The teeth in the experimental groups (80 teeth) were divided into four sub-groups and were obturated by laterally condensed gutta-percha with the two sealer cements as follows: Group A1: smear layer left intact and AH26 cement used as sealer; Group A2: smear layer left intact and Roth 801 cement used as sealer; Group B1: smear layer removed and AH26 cement used as sealer; and Group B2: smear layer removed and Roth 801 cement used as sealer. Coronal microleakage was evaluated by measuring the distance of dye penetration. The data was statistically evaluated using a two-way ANOVA test. The results showed that removal of the smear layer resulted in a statistically significant reduction of microleakage values in the groups obturated with AH26 compared with the groups obturated with Roth 801 sealer. It was concluded that the removal of smear layer has a significant influence on the degree of microleakage in obturated root canals.
authors.affiliation: Department of Endodontics, School of Dental Medicine, Shiraz University of Medical Science, Shiraz, Iran.
authors.forename: Akbar
authors.initials: A
authors.lastname: Khayat
authors.forename: Anahita
authors.initials: A
authors.lastname: Jahanbin
mesh_terms: D000268:Adhesiveness; D000704:Analysis of Variance; D001729:Bismuth; D003763:Dental Leakage / Q000517:prevention & control*; D003804:Dentin / Q000648:ultrastructure; D004338:Drug Combinations; D004853:Epoxy Resins; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011897:Random Allocation; D012387:Root Canal Filling Materials; D012389:Root Canal Obturation / Q000379:methods; D012834:Silver; D016369:Smear Layer; D014025:Titanium; D015035:Zinc Oxide-Eugenol Cement
chemical_list: D004338:Drug Combinations; D004853:Epoxy Resins; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; D012834:Silver; C028044:epoxy resin AH-26; C074935:Roth's 801 Sealer; D014025:Titanium; D001729:Bismuth