title: Intermittent or continuous ultrasonically activated irrigation: micro-computed tomographic evaluation of root canal system cleaning.
abstract: OBJECTIVE
  The aim of this study was to evaluate the efficacy of two passive ultrasonic irrigation (PUI) methods and conventional manual irrigation (CMI) in root canal system (RCS) cleaning.
  
  
  METHODS
  Artificial single-rooted teeth were used. Four lateral canals were made 2 and 7 mm short from the apex. Root canals were filled with a contrast solution. The specimens were divided into four groups (n = 8): PUI1-intermittent flushing; PUI2-continuous flushing; CMI1-at 1 mm; and CMI2-at 3 mm. Micro-computed tomographic images were obtained. New images were taken after the irrigation protocols enabling the evaluation of the contrast solution volume (in mm(3)) within RCS (main and lateral root canals) in comparison to the initial analysis. The comparison among groups was performed using ANOVA and Tukey's tests with 5 % significance level.
  
  
  RESULTS
  There was no difference among PUI1, PUI2, and CMI1 regarding the contrast solution removal from RCS (p > 0.05). These methods demonstrated greater cleaning than CMI2. At the apical third, CMI2 showed lower cleaning capacity when compared to the other methods (p < 0.05).
  
  
  CONCLUSIONS
  PUI with intermittent or continuous flushing and CMI with the needle placed 1 mm from the working length were efficient in cleaning the main and lateral root canals.
  
  
  CONCLUSIONS
  Root canal irrigation plays an important role in cleaning and disinfection of the RCS. Effective apical irrigation is an important procedure during root canal treatment. PUI and CMI (at 1 mm short) were effective in cleaning of the main and simulated lateral root canals.
authors.affiliation: Araraquara School of Dentistry, Araraquara, São Paulo, Brazil. tanomaru@uol.com.br.
authors.forename: Mário
authors.initials: M
authors.lastname: Tanomaru-FIlho
authors.affiliation: Araraquara School of Dentistry, Araraquara, São Paulo, Brazil.
authors.forename: Fernanda Ferrari Esteves
authors.initials: FF
authors.lastname: Torres
authors.affiliation: Araraquara School of Dentistry, Araraquara, São Paulo, Brazil.
authors.forename: Gisselle Moraima
authors.initials: GM
authors.lastname: Chávez-Andrade
authors.affiliation: Araraquara School of Dentistry, Araraquara, São Paulo, Brazil.
authors.forename: Lucas Martinati
authors.initials: LM
authors.lastname: Miano
authors.affiliation: Araraquara School of Dentistry, Araraquara, São Paulo, Brazil.
authors.forename: Juliane Maria
authors.initials: JM
authors.lastname: Guerreiro-Tanomaru
mesh_terms: D003287:Contrast Media; D003786:Dental Pulp Cavity / Q000187:drug effects; D009339:Needles; D012388:Root Canal Irrigants / Q000008:administration & dosage*; D018915:Root Canal Preparation / Q000379:methods*; D007507:Therapeutic Irrigation / Q000379:methods*; D014093:Tooth, Artificial; D014465:Ultrasonics; D055114:X-Ray Microtomography
chemical_list: D003287:Contrast Media; D012388:Root Canal Irrigants
keywords: Contrast; Endodontics; Micro-CT; Passive ultrasonic irrigation