title: Scanning electron microscopy comparison of the cleaning efficacy of a root canal system by Nd:YAG laser and rotary instruments.
abstract: This study evaluated the cleaning efficacy of a root canal system by Nd:YAG laser and rotary instruments. Sixty single-rooted human teeth were divided into four experimental groups (n=15). In the first group the teeth were prepared with a step-back technique using conventional K-files. In the second and third groups, tooth preparation was carried out using Nd:YAG laser and rotary NiTi instruments, respectively. Teeth in the fourth group were prepared by combined laser and rotary methods. The smear layer remaining on canal walls was then assessed by scanning electron microscopy in the coronal, middle, and apical portions. The comparison of smear layer removal efficacy between groups was carried out by Kruskal-Wallis and Mann-Whitney U tests. The mean grades of smear layer removal in rotary-laser, rotary, laser and step-back techniques were 1.34 ± 0.18, 2.2 ± 0.28, 1.91 ± 0.25, and 2.42 ± 0.19, respectively. On the whole, differences between rotary-laser and rotary groups, step-back, and the three other techniques (rotary, laser, and rotary-laser) were significant at p=0.034. Based on the findings of this study, the cleaning efficacy of rotary, laser, and rotary-laser techniques were better than the step-back technique and the combined laser and rotary technique was the most efficient method.
authors.affiliation: 1Department of Endodontics,Tabriz University of Medical Sciences,Tabriz,Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Samiei
authors.affiliation: 2Department of Prosthodontics,Student's research committee,Tabriz University of Medical Sciences,Tabriz,Iran.
authors.forename: Seyyed Mahdi Vahid
authors.initials: SM
authors.lastname: Pakdel
authors.affiliation: 3Department of Restorative dentistry,Tabriz University of Medical Sciences,Tabriz,Iran.
authors.forename: Sahand
authors.initials: S
authors.lastname: Rikhtegaran
authors.affiliation: 1Department of Endodontics,Tabriz University of Medical Sciences,Tabriz,Iran.
authors.forename: Sahar
authors.initials: S
authors.lastname: Shakoei
authors.affiliation: 4Department of Oral medicine,Tabriz University of Medical Sciences,Tabriz,Iran.
authors.forename: Delaram
authors.initials: D
authors.lastname: Ebrahimpour
authors.affiliation: 5Dentist,Private practice,Tabriz,Iran.
authors.forename: Pedram
authors.initials: P
authors.lastname: Taghavi
mesh_terms: D003762:Dental Instruments; D006801:Humans; D053844:Lasers, Solid-State; D008855:Microscopy, Electron, Scanning; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods*