title: Reasons for extraction of permanent teeth in general dental practices in Tehran, Iran.
abstract: OBJECTIVE
  The aim of this survey was to investigate the primary reason for extraction of permanent teeth, its correlations with age, gender and education level, as well as identify the important predictors for dental caries in general dental centers in Tehran, Iran.
  
  
  METHODS
  The study was conducted over a period of 6 months; its population consisted of 1,382 patients, aged 9-95 years, who underwent tooth extraction. There were 673 (47.8%) male and 709 (51.3%) female patients. The frequency distribution was calculated using the χ(2) test, ANOVA and t test for differences in mean number of extracted teeth and the logistic regression model to evaluate the variables associated with reasons for tooth extraction.
  
  
  RESULTS
  A total of 2,620 teeth were extracted from the 1,382 patients. The highest rate (36.9%) of extraction occurred for those 41-60 years old. Males comprised 48.7% of patients but had more teeth (1,470, 55.3%) extracted than females (1,150, 43.9%). Nine hundred and thirty-six (67.7%) patients had incomplete secondary education or less. Tooth loss due to caries was 51%; periodontal disease was 14.4%; supernumerary and tooth impaction 13.9%. There was a significant association between patient characteristics (age, gender and education level) and number of teeth extracted.
  
  
  CONCLUSIONS
  Dental caries and periodontal disease were the main reasons for tooth extraction in Tehran, Iran.
authors.affiliation: Dental Research Center, Research Institute of Dental Sciences of Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Jafarian
authors.forename: A
authors.initials: A
authors.lastname: Etebarian
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002648:Child; D003731:Dental Caries / Q000453:epidemiology / Q000601:surgery; D019229:Dentition, Permanent; D004522:Educational Status; D005260:Female; D005792:General Practice, Dental / Q000706:statistics & numerical data*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010510:Periodontal Diseases / Q000453:epidemiology / Q000601:surgery; D012737:Sex Factors; D014081:Tooth Extraction / Q000706:statistics & numerical data*; D014095:Tooth, Impacted / Q000453:epidemiology / Q000601:surgery; D055815:Young Adult