title: Morphological study of the Er,Cr:YSGG laser for root canal preparation in mandibular incisors with curved root canals.
abstract: OBJECTIVE
  The objectives of this study were to observe morphological changes of root canal walls and to evaluate the capability of Er,Cr:YSGG laser for preparation of curved mandibular incisor root canals in vitro.
  
  
  BACKGROUND
  There are no published reports on the use of Er,Cr:YSGG laser for curved root canal preparation.
  
  
  METHODS
  Twenty curved mandibular incisor root canals (10 and 15 degrees) were prepared sequentially by laser irradiation at 20 Hz, 2 Wusing two different sizes of fine fiber tips (200 and 320 microm in diameters). After laser irradiation, the teeth were bisected longitudinally, and the specimens were observed by stereoscope and scanning electron microscope (SEM).
  
  
  RESULTS
  Root canal walls of the irradiated areas showed step-like appearances and openings of dentinal tubules, and root canal preparation, having curvatures of less than 10 degrees, could be carried out by this laser irradiation.
  
  
  CONCLUSIONS
  Er,Cr:YSGG laser irradiation is capable of preparing root canals having curvatures of less than 10 degrees.
authors.affiliation: Department of Endodontics, Showa University School of Dentistry, Tokyo, Japan. emi@senzoku.showa-u.ac.jp
authors.forename: Emi
authors.initials: E
authors.lastname: Matsuoka
authors.forename: Jayanetti Asiri
authors.initials: JA
authors.lastname: Jayawardena
authors.forename: Koukichi
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D002857:Chromium; D003786:Dental Pulp Cavity / Q000528:radiation effects* / Q000648:ultrastructure*; D004871:Erbium; D006801:Humans; D007180:Incisor / Q000528:radiation effects* / Q000648:ultrastructure; D053685:Laser Therapy; D008855:Microscopy, Electron, Scanning; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D012494:Sampling Studies; D012680:Sensitivity and Specificity
chemical_list: D002857:Chromium; D004871:Erbium