Title: | Quantification by SIFT-MS of volatile compounds produced by the action of sodium hypochlorite on a model system of infected root canal content |
Author(s): | Ioannidis K; Niazi S; Deb S; Mannocci F; Smith D; Turner C; |
Address: | "Division of Tissue Engineering and Biophotonics, Dental Institute, King's College, London, United Kingdom. Department of Restorative Dentistry, Dental Institute, King's College, London, United Kingdom. Trans Spectra Limited, Newcastle-under-Lyme, United Kingdom. School of Life, Health and Chemical Sciences, The Open University, Walton Hall, Milton Keynes, United Kingdom" |
DOI: | 10.1371/journal.pone.0198649 |
ISSN/ISBN: | 1932-6203 (Electronic) 1932-6203 (Linking) |
Abstract: | "Root canal irrigation with sodium hypochlorite (NaOCl) is an indispensable part of the chemomechanical preparation of infected root canals in Endodontology. However, there is limited information on the emergence of toxic or hazardous volatile compounds (VOCs) from the interaction of NaOCl with the infected content of tooth biomaterials. The aim of this study was to assess the formation of VOCs and disinfection by-products (DBPs) following the interaction of NaOCl 2.5% v/v with a model system of different sources of natural organic matter (NOM) present in infected root canals, including dentine powder, planktonic multi-microbial suspensions (Propionibacterium acnes, Staphylococcus epidermidis, Actinomyces radicidentis, Streptococcus mitis and Enterococcus faecalis strain OMGS3202), bovine serum albumin 4%w/v and their combination. NaOCl was obtained from a stock solution with iodometric titration. Ultrapure water served as negative control. Samples were stirred at 37 degrees C in aerobic and anaerobic conditions for 30min to approximate a clinically realistic time. Centrifugation was performed and the supernatants were collected and stored at -800 C until analysis. The reaction products were analysed in real time by selected ion flow tube mass spectrometry (SIFT-MS) in triplicates. SIFT-MS analysis showed that the released VOCs included chlorinated hydrocarbons, particularly chloroform, together with unexpected higher levels of some nitrogenous compounds, especially acetonitrile. No difference was observed between aerobic and anaerobic conditions. The chemical interaction of NaOCl with NOM resulted in the formation of toxic chlorinated VOCs and DBPs. SIFT-MS analysis proved to be an effective analytical method. The risks from the rise of toxic compounds require further consideration in dentistry" |
Keywords: | Bacteria/chemistry Disinfection/methods Hazardous Substances/*analysis Humans Mass Spectrometry/methods Root Canal Irrigants/*chemistry Root Canal Preparation/methods Sodium Hypochlorite/*chemistry Volatile Organic Compounds/*analysis; |
Notes: | "MedlineIoannidis, Konstantinos Niazi, Sadia Deb, Sanjukta Mannocci, Francesco Smith, David Turner, Claire eng 2018/09/11 PLoS One. 2018 Sep 10; 13(9):e0198649. doi: 10.1371/journal.pone.0198649. eCollection 2018" |