title: In vivo efficacy of three different endodontic irrigation systems for irrigant delivery to working length of mesial canals of mandibular molars.
abstract: BACKGROUND
  Many in vitro studies have debated over the ability of different irrigant delivery and/or agitation systems to reach the apical third of curved root canals; however, little is known about irrigant penetration in vivo. Therefore, the purpose of this study was to compare the efficacy of the conventional endodontic irrigation needle, passive ultrasonic irrigation (PUI), and a negative pressure system for irrigant delivery to working length (WL) of mesial canals of mandibular molars.
  
  
  METHODS
  Thirty mesial canals of 30 vital mandibular first or second molars were randomly assigned into 3 groups (n = 10): (1) Monoject syringe with 27-gauge needle; (2) PUI with IrriSafe tip; and (3) EndoVac system. All canals were treated following the same preparation protocol to size 35/0.04 by using 5.25% NaOCl as irrigant during preparation procedure. Before obturation, canals were irrigated with 1 mL of a radiopaque solution by using the assigned irrigation system, and a digital radiograph was taken by using a parallel technique. With the aid of image editing software the distance between WL and maximum irrigant penetration was measured.
  
  
  RESULTS
  Mean distances for Monoject, PUI, and EndoVac groups were 1.51 mm, 0.21 mm, and 0.42 mm, respectively. Analysis of variance test showed statistically significant differences between groups (P < .001). Tukey honestly significant difference test showed statistically significant differences between the Monoject group and the other 2 groups (P < .001) but no significant differences between PUI and EndoVac groups (P = .06).
  
  
  CONCLUSIONS
  PUI and EndoVac are more effective than the conventional endodontic needle in delivering irrigant to WL of root canals.
authors.affiliation: Postgraduate Endodontic Department, School of Dentistry, Universidad de San Carlos de Guatemala, Guatemala City, Guatemala. endoadvance@intelnett.com
authors.forename: Hugo Roberto
authors.initials: HR
authors.lastname: Munoz
authors.forename: Karla
authors.initials: K
authors.lastname: Camacho-Cuadra
mesh_terms: D003287:Contrast Media; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000187:drug effects*; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007472:Iohexol; D008334:Mandible; D008963:Molar / Q000000981:diagnostic imaging / Q000187:drug effects*; D009339:Needles; D019252:Radiography, Dental, Digital; D012388:Root Canal Irrigants / Q000008:administration & dosage*; D018915:Root Canal Preparation / Q000295:instrumentation*; D012973:Sodium Hypochlorite / Q000008:administration & dosage; D013594:Syringes; D007507:Therapeutic Irrigation / Q000295:instrumentation; D019227:Tooth Apex / Q000000981:diagnostic imaging / Q000187:drug effects; D016896:Treatment Outcome; D014465:Ultrasonics / Q000295:instrumentation; D014618:Vacuum
chemical_list: D003287:Contrast Media; D012388:Root Canal Irrigants; D007472:Iohexol; D012973:Sodium Hypochlorite