title: Scanning electron microscopic analysis of the integrity of the root-end surface after root-end management using a piezoelectric device: a cadaveric study.
abstract: BACKGROUND
  The introduction of piezoelectric instruments in endodontic surgery allowed clinicians to manage the bone tissue with precision reducing the risk of damaging soft tissues. Although such instruments can also be used to prepare root-end cavity, few information is available on the effect of piezosurgery on dentine. This cadaveric study investigated the integrity of root apices after root-end cavity preparation by piezoelectric instruments at different device settings.
  
  
  METHODS
  Fifty maxillary anterior teeth underwent endodontic treatment and apical resection in situ. Ten teeth were used as control. Retrograde cavities were prepared in 40 teeth (10 per group). In three groups, the piezoelectric device was set at constant vibration mode (CV), and three power levels were used. In another experimental group (n = 10), vibration + pulsation mode (VP) was selected, and low power was used. Each root was duplicated and analyzed by scanning electron microscopy for the presence of cracks and marginal chipping.
  
  
  RESULTS
  The number of cracks was significantly higher in the VP group, whereas no significant difference was found among CV groups. No difference between groups was found for crack type. The VP group showed a significantly poorer quality of cavity margin respect to the CV groups.
  
  
  CONCLUSIONS
  Constant vibration mode is recommended for retrograde preparation with piezosurgery.
authors.affiliation: IRCCS Galeazzi Orthopaedic Institute, Dental Clinic, CRSO (Centro di Ricerca per la Salute Orale), Department of Health Technologies, University of Milan, Milan, Italy. massimo.delfabbro@unimi.it
authors.forename: Massimo
authors.initials: M
authors.lastname: Del Fabbro
authors.forename: Igor
authors.initials: I
authors.lastname: Tsesis
authors.forename: Gabriele
authors.initials: G
authors.lastname: Rosano
authors.forename: Monica
authors.initials: M
authors.lastname: Bortolin
authors.forename: Silvio
authors.initials: S
authors.lastname: Taschieri
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001047:Apicoectomy; D002102:Cadaver; D016009:Chi-Square Distribution; D003804:Dentin / Q000473:pathology / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D012184:Retrograde Obturation; D018915:Root Canal Preparation / Q000295:instrumentation*; D019227:Tooth Apex / Q000601:surgery* / Q000648:ultrastructure*; D014465:Ultrasonics; D014732:Vibration