title: Dental and prosthodontic status of an over 40 year-old population in Shandong Province, China.
abstract: BACKGROUND
  This study aims to (1) describe the dental status using DMFT for the whole dentition and the anterior, premolar and molar regions; (2) determine associations of demographic variables and socio-economic status (SES) with DMFT and tooth replacement; (3) analyze to what extent the goal as proposed by the WHO -'the retention of not less than 20 teeth throughout life' is achieved.
  
  
  METHODS
  DMFT and tooth replacement data of 1588 subjects over 40 years from urban and rural sites in Qingdao (Shandong Province, China) were collected. Relative D, M, and F scores per dental region were calculated and compared by paired T-tests. Multivariable logistic regression was used to determine relationships with age, gender, place of residence, and SES.
  
  
  RESULTS
  Mean numbers of D and F were low (1.36 respectively 0.27) at all ages. Molars had highest chance for D and M. For the molar region every additional year of age gave significantly lower chance for D and higher chance for M (OR: 0.98 and 1.02 respectively; both p ≤ 0.01). Mean number of M was associated with age (approximately 1.5 in each jaw at 40 years and 6 at 80 years). Females had higher chance for D (OR: 1.34; p ≤ 0.05) and F (OR: 1.69; p ≤ 0.01), and lower chance for M (OR: 0.60; p ≤ 0.01). Urban and rural subjects had similar chance for D; urban subjects had approximately 5 times more chance for F (p ≤ 0.01). SES had no relationship with D and M, however SES low was associated with F (OR: 0.45; p ≤ 0.01). Replacements were significantly associated with age (all dental regions except anterior region), gender (all dental regions), place of residence (whole dentition and molar region), and SES (whole dentition and premolar and molar regions).
  
  
  CONCLUSIONS
  The majority of subjects presented a reduced dentition. Molars were most frequently affected by D and M. D, M, F and replaced teeth were associated with the background variables, however differently for different dental regions. Above the age of 70 years, only 64% of the subjects presented 'not less than 20 natural teeth'.
authors.affiliation: Department of Prosthetic Dentistry, Affiliated Hospital of Medical School, Qingdao University, Jiangsu Road 16#, Qingdao, P.R. China. q.zhang@dent.umcn.nl
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Witter
authors.forename: Ewald M
authors.initials: EM
authors.lastname: Bronkhorst
authors.forename: Nico H J
authors.initials: NH
authors.lastname: Creugers
mesh_terms: D000328:Adult; D000368:Aged; D002681:China; D003430:Cross-Sectional Studies; D003731:Dental Caries / Q000453:epidemiology / Q000628:therapy; D003753:Dental Health Surveys; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009909:Oral Health; D011476:Prosthodontics; D016388:Tooth Loss / Q000453:epidemiology / Q000628:therapy