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An overview of systematic reviews on endotoxins in endodontic infections and the effectiveness of root canal therapy in its removal


Background The objective of this overview was to synthesise the current evidence on the role of endotoxins in endodontics infections and to evaluate the effectiveness of endodontic procedures in its removal using information from published systematic reviews.

Methods Electronic databases Medline, Scopus, Embase, Cochrane Library and Google Scholar were searched for reviews published up to July 2021. Systematic reviews on endotoxins based on clinical and/or observational studies were included. The quality of systematic reviews was assessed with the AMSTAR2 tool.

Results A total of five systematic reviews were selected, of which two reviews were of high quality. A significantly higher level of endotoxins were found in teeth with exudation, teeth with a previous episode of pain and pain on percussion. Chemomechanical preparation of root canals significantly reduce endotoxin levels. Calcium hydroxide intracanal medication in symptomatic teeth was significantly effective in endotoxin reduction (standardised mean difference -1.051 [95% confidence interval -2.039 to -0.063]; p <0.05; I2 = 83.3%; certainty of evidence = very low). Multiple session root canal treatment in teeth with symptomatic apical periodontitis was significantly more effective in endotoxins/lipopolysaccharides removal than single-session treatment.

Conclusion Limited quality of evidence showed a significant association of endotoxins in infected teeth with clinical symptoms. Conventional chemomechanical preparation of root canals and intracanal medication were unable to eliminate endotoxins from the root canal system. Future evolution of effective disinfection therapies is warranted.

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Muhammad Z. Ahmad: conceptualisation, data extraction, methodology, writing, reviewing and editing. Durre Sadaf: conceptualisation, methodology, data extraction, software and writing original draft. Khalid A. Merdad: reviewing and validation.

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Correspondence to Durre Sadaf.

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The protocol of this overview was registered in PROSPERO (CRD #42021267175) on 23 July 2021.We did not amend any information in the article provided at registration. The authors declare no conflicts of interest. The review was not funded by any commercial source.

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Ahmad, M., Merdad, K. & Sadaf, D. An overview of systematic reviews on endotoxins in endodontic infections and the effectiveness of root canal therapy in its removal. Evid Based Dent (2022).

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