title: Poor oral health as a risk factor for esophageal squamous dysplasia in northeastern Iran.
abstract: BACKGROUND
  Northeastern Iran has one of the highest rates of esophageal squamous cell carcinoma (ESCC) in the world. The reasons for observing such high rates of ESCC in this area are not fully clear. The current study evaluates the association between some potential risk factors and squamous dysplasia, a precursor lesion of ESCC, in northeastern Iran.
  
  
  METHODS
  Using logistic regression, we compared potential risk factors of ESCC in 124 individuals with dysplasia and 50 normal individuals from northeastern Iran. Case/control status was histologically proven in all 174 study participants.
  
  
  RESULTS
  Poor oral health showed a dose-response association with ESCC risk (p for trend < 0.01). Edentulous individuals had 5-fold higher risk of dysplasia compared to participants with good oral health (p-value < 0.01).
  
  
  CONCLUSIONS
  Our results are consistent with two other published studies that have shown oral health as a risk factor for ESCC. The high incidence of ESCC in northeastern Iran may be partly attributable to poor oral health.
authors.affiliation: Cancer Prevention Studies Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 21218, USA.
authors.forename: Alireza
authors.initials: A
authors.lastname: Sepehr
authors.forename: Farin
authors.initials: F
authors.lastname: Kamangar
authors.forename: Saman
authors.initials: S
authors.lastname: Fahimi
authors.forename: Farrokh
authors.initials: F
authors.lastname: Saidi
authors.forename: Christian C
authors.initials: CC
authors.lastname: Abnet
authors.forename: Sanford M
authors.initials: SM
authors.lastname: Dawsey
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000209:etiology; D016022:Case-Control Studies; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006801:Humans; D007492:Iran; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000209:etiology; D016017:Odds Ratio; D009909:Oral Health; D011230:Precancerous Conditions / Q000175:diagnosis* / Q000209:etiology; D012307:Risk Factors