title: Efficacy of Laser-Activated Irrigants in Calcium Hydroxide Removal from the Artificial Grooves in Root Canals: An Ex Vivo Study.
abstract: OBJECTIVE
  The aim of this study was to investigate the efficacy of an erbium chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser with different irrigation solutions [sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), QMix 2in1, and peracetic acid] in removing calcium hydroxide (CH) from artificial grooves created in root canals.
  
  
  BACKGROUND
  CH has to be removed totally before the root canal filling. Any CH residue on the dentin walls may affect the dentinal bond strength and the penetration of sealers into the dentin tubules, and may increase apical leakage. In addition, such a remnant could react chemically with sealers and, possibly, influence physical properties. Therefore, complete removal of CH placed inside the root canals is recommended, using various products and techniques.
  
  
  METHODS
  The root canals of 160 extracted single-rooted mandibular premolars were prepared with ProTaper Universal rotary instruments up to size F4. The roots were split longitudinally along the length of the instrumented canals, and a standardized groove was prepared in the apical part of one segment. CH powder mixed with distilled water was placed into the grooves, and the root halves were then reassembled. The roots were randomly divided into two main groups according to the selected irrigation techniques (needle and laser activation) and then each main group was divided into four subgroups according to the final irrigation (NaOCl, EDTA, QMix 2in1, and peracetic acid) protocols used. After irrigation, the roots were disassembled and digital images were taken using a stereomicroscope. Measurements of residual CH were performed as percentages of the overall groove surface area with image analysis software. The data obtained were analyzed using one way analysis of variance and Tukey's honest significant difference tests. Statistical significance was set at p < 0.05.
  
  
  RESULTS
  Significantly less residual CH was obtained in the laser-activated groups than in the needle-irrigated groups (p < 0.05). According to both main groups' data, NaOCl left significantly more CH than the other groups (p < 0.05). However, there was no significant difference among the EDTA, QMix 2in1, and peracetic acid groups.
  
  
  CONCLUSIONS
  None of the techniques removed the CH dressing completely. Laser-activated irrigation was significantly more effective than needle irrigation.
authors.affiliation: 1 Department of Endodontics, Faculty of Dentistry, Akdeniz University, Antalya, Turkey .
authors.forename: Alper
authors.initials: A
authors.lastname: Kuştarcı
authors.affiliation: 1 Department of Endodontics, Faculty of Dentistry, Akdeniz University, Antalya, Turkey .
authors.forename: Kürşat
authors.initials: K
authors.lastname: Er
authors.affiliation: 2 Restorative Dentistry, Faculty of Dentistry, Bezmialem Vakif University, Istanbul, Turkey .
authors.forename: Seyda Hergüner
authors.initials: SH
authors.lastname: Siso
authors.affiliation: 1 Department of Endodontics, Faculty of Dentistry, Akdeniz University, Antalya, Turkey .
authors.forename: Hakan
authors.initials: H
authors.lastname: Aydın
authors.affiliation: 1 Department of Endodontics, Faculty of Dentistry, Akdeniz University, Antalya, Turkey .
authors.forename: Hatice
authors.initials: H
authors.lastname: Harorlı
authors.affiliation: 3 Department of Endodontics, Faculty of Dentistry, Bezmialem Vakif University, Istanbul, Turkey .
authors.forename: Dilara
authors.initials: D
authors.lastname: Arslan
authors.affiliation: 4 Department of Prosthodontics, Faculty of Dentistry, Akdeniz University , Antalya, Turkey .
authors.forename: Omer
authors.initials: O
authors.lastname: Kirmali
mesh_terms: D001641:Bicuspid; D003786:Dental Pulp Cavity; D004492:Edetic Acid / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000494:pharmacology*; D012973:Sodium Hypochlorite / Q000494:pharmacology*; D013499:Surface Properties; D007507:Therapeutic Irrigation / Q000295:instrumentation*
chemical_list: D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite