title: Possibility of root canal preparation by Er:YAG laser.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the cutting efficiency and morphological changes of root dentin irradiated by an Er:YAG laser in vitro.
  
  
  METHODS
  Thirty-two root dentin blocks were divided into 4 groups. The irradiation conditions were as follows: Group 1 (G1): 30 mJ, 10 pps, 1 mm/s, 20 times; Group 2 (G2): 30 mJ, 10 pps, 1 mm/s, 10 times; Group 3 (G3): 30 mJ, 10 pps, 2 mm/s, 20 times; and Group 4 (G4): 30 mJ, 25 pps, 1 mm/s, 10 times. After being irradiated, the blocks were observed by mu-CT and their width and depth were measured. Moreover, SEM observations were performed.
  
  
  RESULTS
  There were significant differences between G1 and G2, between G1 and G3, between G2 and G4, and between G3 and G4 for both width and depth (P < .05). The SEM observations showed that no smear layer was present on the surface of any of the samples.
  
  
  CONCLUSIONS
  These results show that the Er:YAG laser operated under the conditions used in this study is an effective tool for root canal preparation.
authors.affiliation: Department of Endodontics, School of Dentistry, Aichi Gakuin University, Aichi, Japan. kyon@dpc.agu.ac.jp
authors.forename: Kyoko
authors.initials: K
authors.lastname: Inamoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Horiba
authors.forename: Shinpei
authors.initials: S
authors.lastname: Senda
authors.forename: Munetaka
authors.initials: M
authors.lastname: Naitoh
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Ariji
authors.forename: Akira
authors.initials: A
authors.lastname: Senda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D003804:Dentin / Q000601:surgery*; D006801:Humans; D053685:Laser Therapy; D053844:Lasers, Solid-State; D018915:Root Canal Preparation / Q000295:instrumentation*; D016369:Smear Layer