Influence of an apical negative pressure irrigation system on bacterial elimination during endodontic therapy: a prospective randomized clinical study

J Endod. 2012 Sep;38(9):1177-81. doi: 10.1016/j.joen.2012.06.013. Epub 2012 Jul 11.


Introduction: Recent in vitro studies that use an apical negative pressure irrigation system, EndoVac, have demonstrated promising results in the production of debris-free root canals, while also preventing potential extrusion of irrigants into the periapical region. We conducted a randomized, controlled, prospective clinical study to determine whether the use of EndoVac irrigation (EndoVac group) was more efficient compared with standard needle irrigation (control group) in obtaining canals from which microbes could not be cultivated.

Methods: Routine endodontic therapy was performed in 48 patients with necrotic, single-rooted, single-canal teeth. The patients were randomly assigned to either the EndoVac group (n = 25) or control group (n = 23). Irrigation with either method was carried out with 0.5% sodium hypochlorite. After surface disinfection, before instrumentation and on completion of chemomechanical preparation, intracanal microbial samples were obtained and cultured under anaerobic conditions. The frequency of microbial cultivability by using either irrigation system was analyzed.

Results: The frequency of obtaining culture-negative root canals was 90.9% and 82.6% for the control group and EndoVac group, respectively. There was no significant difference in the antimicrobial efficacy of either control group or EndoVac group (Fisher exact test, P = .665). Furthermore, no significant association between study variables and the irrigation systems' antimicrobial efficacy was found (P > .05).

Conclusions: The results of this prospective in vivo study demonstrate that the antimicrobial efficacy of EndoVac irrigation is comparable to that of standard irrigation.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Bacteria / drug effects*
  • Bacteriological Techniques
  • Calcium Hydroxide / administration & dosage
  • Dental Disinfectants / therapeutic use
  • Dental Pulp Cavity / microbiology*
  • Dental Pulp Necrosis / microbiology
  • Dental Pulp Necrosis / therapy
  • Disinfection / methods
  • Edetic Acid / administration & dosage
  • Humans
  • Hydrogen Peroxide / therapeutic use
  • Microinjections / instrumentation
  • Periapical Periodontitis / microbiology
  • Periapical Periodontitis / therapy
  • Prospective Studies
  • Root Canal Irrigants / administration & dosage*
  • Root Canal Preparation / instrumentation
  • Root Canal Preparation / methods*
  • Sodium Hypochlorite / administration & dosage
  • Therapeutic Irrigation / instrumentation
  • Therapeutic Irrigation / methods*
  • Treatment Outcome


  • Dental Disinfectants
  • Root Canal Irrigants
  • Edetic Acid
  • Hydrogen Peroxide
  • Sodium Hypochlorite
  • Calcium Hydroxide