title: Effect of passive ultrasonic irrigation on diffusion of hydroxyl ion through radicular dentine.
abstract: OBJECTIVE
  This study investigated the effect of passive ultrasonic irrigation (PUI) on diffusion of hydroxyl ions through radicular dentine.
  
  
  METHODS
  After chemomechanical preparation of root canals in 60 human teeth, the cementoenamel junction and the apical 3 mm of each root were covered with fast-setting adhesive. Four final irrigation protocols were applied (n = 10): group (G)1: irrigation with EDTA + NaOCl; G2: EDTA + PUI + NaOCl; G3: EDTA+(NaOCl + PUI); G4: (EDTA + PUI) + (NaOCl + PUI). Ten teeth irrigated with distilled water followed by PUI (G5) served as the negative control. After drying, the canals were filled with calcium hydroxide paste (CH), sealed and kept in individual vials containing 10 mL of distilled water with known pH values. At 7, 14, and 21 days, the pH of the water in the vials was measured. The pH values in various groups were analyzed with two-way ANOVA (irrigation protocol and time period as factors) and Holm-Sidak multiple comparison test (α = 0.05).
  
  
  RESULTS
  Changes in pH was not significantly different among groups (P = 0.651) but was significant different among different time periods (P < 0.0001). For all groups, ion diffusion was higher at 14 and 21 days than at 7 days.
  
  
  CONCLUSIONS
  PUI has no effect on diffusion of hydroxyl ions through radicular dentine. When CH is used as temporary filling material, a waiting period of at least 14 days is required to create an alkaline environment within the radicular dentine.
  
  
  CONCLUSIONS
  The use of PUI during final irrigation phase does not improve the action of CH when it is used as temporary filling material.
authors.affiliation: Postgraduate Program of the Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Fernanda Helaine
authors.initials: FH
authors.lastname: Cidade
authors.affiliation: Postgraduate Program of the Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Tamer Ferreira
authors.initials: TF
authors.lastname: Schmidt
authors.affiliation: Postgraduate Program of the Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Luciane Geanini Pena
authors.initials: LG
authors.lastname: Dos Santos
authors.affiliation: Department of Endodontics, College of Dental Medicine, Georgia Regents University, Augusta, GA, USA.
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
authors.affiliation: Discipline of Endodontics, Department of Dentistry, Campus Universitário Reitor João David Ferreira Lima, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil, Zip Code: 88040-900.
authors.forename: Cleonice
authors.initials: C
authors.lastname: da Silveira Teixeira
authors.affiliation: Discipline of Endodontics, Department of Dentistry, Campus Universitário Reitor João David Ferreira Lima, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil, Zip Code: 88040-900.
authors.forename: Mara Cristina Santos
authors.initials: MC
authors.lastname: Felippe
authors.affiliation: Discipline of Endodontics, Department of Dentistry, Campus Universitário Reitor João David Ferreira Lima, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil, Zip Code: 88040-900. edubortoluzzi@hotmail.com.
authors.forename: Eduardo Antunes
authors.initials: EA
authors.lastname: Bortoluzzi
mesh_terms: D002126:Calcium Hydroxide / Q000494:pharmacology; D003804:Dentin / Q000378:metabolism*; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000378:metabolism*; D066298:In Vitro Techniques; D012387:Root Canal Filling Materials / Q000494:pharmacology; D012388:Root Canal Irrigants / Q000494:pharmacology*; D018915:Root Canal Preparation; D012973:Sodium Hypochlorite / Q000494:pharmacology; D007507:Therapeutic Irrigation / Q000379:methods*; D014465:Ultrasonics
chemical_list: D006878:Hydroxides; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C031356:hydroxide ion; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D002126:Calcium Hydroxide
keywords: Calcium hydroxide; EDTA; Irrigation; NaOCl; Smear layer; Ultrasound