title: Dental treatment and risk of variant CJD--a case control study.
abstract: OBJECTIVE
  Knowledge of risk factors for variant CJD (vCJD) remains limited, but transmission of prion proteins via re-useable medical devices, including dental instruments, or enhanced susceptibility following trauma to the oral cavity is a concern. This study aimed to identify whether previous dental treatment is a risk factor for development of vCJD.
  
  
  METHODS
  Case control study.
  
  
  METHODS
  Risk factor questionnaires completed by interview with relatives of 130 vCJD patients and with relatives of 66 community and 53 hospital controls were examined by a dental surgeon. Responses regarding dental treatments were analysed.
  
  
  RESULTS
  We did not find a statistically significant excess of risk of vCJD associated with dental treatments with the exception of extractions in an unmatched analysis of vCJD cases with community controls (p = 0.02). However, this result may be explained by multiple testing.
  
  
  CONCLUSIONS
  This is the first published study to date to examine potential links between vCJD and dental treatment. There was no convincing evidence found of an increased risk of variant CJD associated with reported dental treatment. However, the power of the study is restricted by the number of vCJD cases to date and does not preclude the possibility that some cases have resulted from secondary transmission via dental procedures. Due to the limitations of the data available, more detailed analyses of dental records are required to fully exclude the possibility of transmission via dental treatment.
authors.affiliation: National Creutzfeldt-Jakob Disease Surveillance Unit, The University of Edinburgh, Western General Hospital, Edinburgh, UK.
authors.forename: D
authors.initials: D
authors.lastname: Everington
authors.forename: A J
authors.initials: AJ
authors.lastname: Smith
authors.forename: H J T
authors.initials: HJ
authors.lastname: Ward
authors.forename: S
authors.initials: S
authors.lastname: Letters
authors.forename: R G
authors.initials: RG
authors.lastname: Will
authors.forename: J
authors.initials: J
authors.lastname: Bagg
mesh_terms: D016022:Case-Control Studies; D007562:Creutzfeldt-Jakob Syndrome / Q000209:etiology / Q000635:transmission*; D003729:Dental Care / Q000009:adverse effects*; D003762:Dental Instruments / Q000009:adverse effects*; D017266:Dental Prosthesis / Q000009:adverse effects; D004866:Equipment Contamination; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D012306:Risk; D012390:Root Canal Therapy / Q000009:adverse effects; D011795:Surveys and Questionnaires; D014081:Tooth Extraction / Q000009:adverse effects