title: The comparative effectiveness and safety of three activated irrigation techniques in the isthmus area using a transparent tooth model.
abstract: OBJECTIVE
  To compare the effectiveness and safety of three activated irrigation techniques when removing pulp tissue from the isthmus of a transparent tooth model. The three techniques assessed were: the EndoVac (EV), passive ultrasonic irrigation (PUI) and ultrasonic wave aspiration (TUWA). Conventional syringe irrigation (CSI) was used as a control.
  
  
  METHODS
  A transparent tooth model was created using the mesial root of an extracted mandibular first molar that had an isthmus and two independent mesial canals. An artificial 0.3-mL cylindrical chamber was created below the apical foramen. The tooth was then cleared. After preparation, the root canals were filled with fuchsine-stained bovine pulp tissue. The irrigation protocols were compared in respect of their effectiveness at removing pulp tissue from the isthmus and their safety with regard to irrigant extrusion. For all four groups, 5.25% sodium hypochlorite solution was used as the irrigant. Photographs were taken and analysed using an imaging software. A Kruskal-Wallis test was used to detect the differences between groups (statistical significance was set at P < 0.05).
  
  
  RESULTS
  No group was associated with extrusion of irrigant beyond the apex. Significant differences were observed between the groups: TUWA was the most effective technique at removing pulp tissue from the isthmus (3.39 mm2; standard deviation (SD) = 0.67; range = 1.25-3.69), followed by PUI (2.16 mm2; SD = 0.38; range = 1.37-2.96), EV (0.73 mm2; SD = 0.14; range = 0.49-0.98) and CSI (0.27 mm2; SD = 0.01; range = 0.26-0.28).
  
  
  CONCLUSIONS
  Ultrasonic wave aspiration was the most effective technique at removing artificial pulp tissue from the isthmus of a transparent tooth model. None of the techniques extruded irrigant.
authors.affiliation: Private Practice, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Malentacca
authors.affiliation: Private Practice, Frosinone, Italy.
authors.forename: U
authors.initials: U
authors.lastname: Uccioli
authors.affiliation: Conservative Dentistry and Endodontology, Guy's Dental Hospital, King's College London Dental Institute, London, UK.
authors.forename: F
authors.initials: F
authors.lastname: Mannocci
authors.affiliation: Conservative Dentistry and Endodontology, Guy's Dental Hospital, King's College London Dental Institute, London, UK.
authors.forename: B
authors.initials: B
authors.lastname: Bhuva
authors.affiliation: Private Practice, Rome, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Zangari
authors.affiliation: Private Practice, Caserta, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Pulella
authors.affiliation: Oral Medicine and Pathology, School of Dentistry, Catholic University, Rome, Italy.
authors.forename: C
authors.identifier: http://orcid.org/0000-0003-4663-9734
authors.initials: C
authors.lastname: Lajolo
mesh_terms: D003786:Dental Pulp Cavity; D006801:Humans; D008953:Models, Anatomic; D012388:Root Canal Irrigants; D007507:Therapeutic Irrigation / Q000295:instrumentation / Q000379:methods*; D014464:Ultrasonic Therapy / Q000295:instrumentation
chemical_list: D012388:Root Canal Irrigants
keywords: efficacy; negative pressure irrigation; safety; sodium hypochlorite; ultrasonic irrigation; ultrasonic needle