title: Outcome of Er,Cr:YSGG laser-assisted treatment of teeth with apical periodontitis: a blind randomized clinical trial.
abstract: OBJECTIVE
  As clinical studies conducted to explore the safety and efficacy of new procedures are considered an important focus in endodontic research, the aim of this controlled clinical study was to compare a laser-assisted endodontic treatment using an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser and radial firing tips (RFT) versus the conventional use of 3% sodium hypochlorite and interim calcium hydroxide paste, in teeth with chronic apical periodontitis.
  
  
  METHODS
  Forty-three single-rooted and premolar teeth were randomly assigned. In group 1, teeth were prepared and irrigated with 3% sodium hypochlorite and calcium hydroxide inter-appointment dressing was applied; in group 2 teeth were prepared with saline solution and irradiated with Er,Cr:YSGG laser using RFT2 (140 μs, 37.5 mJ, 20 Hz) and RFT3 (140 μs, 62.5 mJ, 20 Hz) at the first and second appointments, respectively, four times each, moving at 2 mm/sec(-1) from apical to coronal. The primary outcome measure was change in apical bone density at 12 months, using the periapical index (PAI) for blind radiographic assessment.
  
  
  RESULTS
  Thirty teeth were examined and subjected to statistical analysis, 12 in the control group and 18 in the test group. There were two treatment failures in the control group that were not included for analysis; both groups exhibited statistically significant decreases in PAI scores.
  
  
  CONCLUSIONS
  The present findings suggest that for single-rooted and premolar teeth, this laser-assisted protocol can achieve predictable endodontic outcomes, comparable to conventional strategies in 1 year of follow-up.
authors: 1 Department of Endodontics, Faculdade de Medicina Dentária, Universidade do Porto , Portugal .
authors: Miguel R
authors: MR
authors: Martins
authors: Manuel F
authors: MF
authors: Carvalho
authors: Irene
authors: I
authors: Pina-Vaz
authors: Jose A
authors: JA
authors: Capelas
authors: Miguel A
authors: MA
authors: Martins
authors: Norbert
authors: N
authors: Gutknecht
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010485:Periapical Periodontitis / Q000628:therapy*; D010512:Periodontal Index; D055815:Young Adult