title: Anatomy of sodium hypochlorite accidents involving facial ecchymosis - a review.
abstract: OBJECTIVE
  Root canal treatment forms an essential part of general dental practice. Sodium hypochlorite (NaOCl) is the most commonly used irrigant in endodontics due to its ability to dissolve organic soft tissues in the root canal system and its action as a potent antimicrobial agent. Although NaOCl accidents created by extrusion of the irrigant through root apices are relatively rare and are seldom life-threatening, they do create substantial morbidity when they occur.
  
  
  METHODS
  To date, NaOCl accidents have only been published as isolated case reports. Although previous studies have attempted to summarise the symptoms involved in these case reports, there was no endeavour to analyse the distribution of soft tissue distribution in those reports. In this review, the anatomy of a classical NaOCl accident that involves facial swelling and ecchymosis is discussed.
  
  
  RESULTS
  By summarising the facial manifestations presented in previous case reports, a novel hypothesis that involves intravenous infusion of extruded NaOCl into the facial vein via non-collapsible venous sinusoids within the cancellous bone is presented.
  
  
  CONCLUSIONS
  Understanding the mechanism involved in precipitating a classic NaOCl accident will enable the profession to make the best decision regarding the choice of irrigant delivery techniques in root canal débridement, and for manufacturers to design and improve their irrigation systems to achieve maximum safety and efficient cleanliness of the root canal system.
authors.affiliation: Department of Stomatology, North Sichuan Medical College, Nanchong, China.
authors.forename: Wan-chun
authors.initials: WC
authors.lastname: Zhu
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Gyamfi
authors.forename: Li-na
authors.initials: LN
authors.lastname: Niu
authors.forename: G John
authors.initials: GJ
authors.lastname: Schoeffel
authors.forename: Si-ying
authors.initials: SY
authors.lastname: Liu
authors.forename: Filippo
authors.initials: F
authors.lastname: Santarcangelo
authors.forename: Sara
authors.initials: S
authors.lastname: Khan
authors.forename: Kelvin C-Y
authors.initials: KC
authors.lastname: Tay
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
mesh_terms: D000059:Accidents; D004438:Ecchymosis / Q000139:chemically induced*; D004487:Edema / Q000139:chemically induced; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000209:etiology; D005148:Facial Dermatoses / Q000139:chemically induced*; D006801:Humans; D012388:Root Canal Irrigants / Q000009:adverse effects*; D012973:Sodium Hypochlorite / Q000009:adverse effects*
chemical_list: D012388:Root Canal Irrigants; D012973:Sodium Hypochlorite
keywords: Central venous pressure; Ecchymosis; Facial vein; Intraosseous space; Positive fluid pressure; Root canal treatment; Sodium hypochlorite