title: Risk assessment of transmission of sporadic Creutzfeldt-Jakob disease in endodontic practice in absence of adequate prion inactivation.
abstract: BACKGROUND
  Experimental results evidenced the infectious potential of the dental pulp of animals infected with transmissible spongiform encephalopathies (TSE). This route of iatrogenic transmission of sporadic Creutzfeldt-Jakob disease (sCJD) may exist in humans via reused endodontic instruments if inadequate prion decontamination procedures are used.
  
  
  RESULTS
  To assess this risk, 10 critical parameters in the transmission process were identified, starting with contamination of an endodontic file during treatment of an infectious sCJD patient and ending with possible infection of a subsequent susceptible patient. It was assumed that a dose-risk response existed, with no-risk below threshold values. Plausible ranges of those parameters were obtained through literature search and expert opinions, and a sensitivity analysis was conducted. Without effective prion-deactivation procedures, the risk of being infected during endodontic treatment ranged between 3.4 and 13 per million procedures. The probability that more than one case was infected secondary to endodontic treatment of an infected sCJD patient ranged from 47% to 77% depending on the assumed quantity of infective material necessary for disease transmission. If current official recommendations on endodontic instrument decontamination were strictly followed, the risk of secondary infection would become quasi-null.
  
  
  CONCLUSIONS
  The risk of sCJD transmission through endodontic procedure compares with other health care risks of current concern such as death after liver biopsy or during general anaesthesia. These results show that single instrument use or adequate prion-decontamination procedures like those recently implemented in dental practice must be rigorously enforced.
authors.affiliation: Université Pierre et Marie Curie-Paris6, Unité de Recherche Epidémiologie-Systèmes d'information-Modélisation, UMR S 707, Paris, France.
authors.forename: Nadège
authors.initials: N
authors.lastname: Bourvis
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Boelle
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Cesbron
authors.forename: Alain-Jacques
authors.initials: AJ
authors.lastname: Valleron
mesh_terms: D007562:Creutzfeldt-Jakob Syndrome / Q000453:epidemiology / Q000635:transmission*; D004708:Endodontics; D005060:Europe / Q000453:epidemiology; D006801:Humans; D008962:Models, Theoretical; D011328:Prions / Q000037:antagonists & inhibitors*; D018570:Risk Assessment; D035501:Uncertainty
chemical_list: D011328:Prions