VOL. 9 NO. 4 DECEMBER 2020 journals.sagepub.com/home/PRD 59 © The Author(s) 2020. Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/2050168420963308 SHALINI KANAGASINGAM, IGOR R. BLUM Prim Dent J. 2020;9(4):59-63 SODIUM HYPOCHLORITE EXTRUSION ACCIDENTS: MANAGEMENT AND MEDICO-LEGAL CONSIDERATIONS 963308PRD Primary Dental Journal AUTHORS Shalini Kanagasingam BDS (Mal) MClinDent Endodontology (Lon) MFDS RCS (Eng) MRD RCS (Edin) MFDS RCPS (Glasg)MRestDent RCPS (Glasg) FHEA Senior Clinical Lecturer, Course Lead MSc and MClinDent in Endodontology School of Dentistry, Faculty of Clinical and Biomedical Sciences, University of Central Lancashire, Preston, UK Igor R. Blum DDS (Hons), PhD, Dr Med Dent, MSc, MFDS RCS (Eng), MFDS RCS (Edin), FDS (Rest Dent) RCS, FFGDP(UK), FCGDent, PGCHE, FHEA, LLM (Medico-Legal) Consultant and Specialist in Restorative Dentistry; Reader in Primary Dental Care and Advanced General Dental Practice, Faculty of Dentistry, Oral and Craniofacial Sciences, King’s College London, UK ABSTRACT Sodium hypochlorite is considered the most widely used irrigant in endodontics as it exhibits effective antimicrobial activity and has potent tissue-dissolving ability. Whilst it is considered safe when used within the confines of the root canal system, it can cause serious complications when inadvertent periradicular extrusion occurs. This article outlines the complications of sodium hypochlorite extrusion and reviews the appropriate management based on the contemporary evidence. Preventive measures are suggested and the relevant medico-legal considerations are outlined. KEY WORDS Sodium hypochlorite accident, apical extrusion, complication, adverse event, medico-legal LEARNING OBJECTIVES • To understand the nature of injuries associated with periradicular exposure to sodium hypochlorite • To determine the appropriate management strategy at various stages post injury • To appreciate the importance of implementing precautionary measures to prevent sodium hypochlorite accidents • To understand the medico-legal implications when faced with a sodium hypochlorite extrusion accident Introduction Sodium hypochlorite (NaOCl) is the irrigant of choice for root canal treatment, owing to its superior antibacterial properties and its efficient tissue-dissolving abilities. 1 It is a strong alkaline solution (pH >11) which degrades the fatty acids and amino acids of the organic components of the dental pulp. By irreversibly inhibiting microbial enzymes and destroying their cell membranes, NaOCl has a proven broad spectrum bactericidal, sporicidal and virucidal activity. 2 The ideal concentration of NaOCl is still a matter of debate with most clinicians choosing 0.5% to 5.25%. Whilst most in vitro studies report faster and increased bactericidal effects at higher concentrations, 3,4 clinical studies have shown similar outcomes with both lower and higher concentrations. 5,6 Bearing in mind that highly concentrated solutions exhibit higher cytotoxicity, this is especially worrying when unintended accidents occur. Accidental spillage of NaOCl can be caustic to vital tissues and damage clothing. One of the most traumatic injuries to a patient occurs when NaOCl is extruded into the periradicular tissues. This is commonly caused by iatrogenic errors associated with poor irrigation techniques and