title: Dental functional status in a southern vietnamese adult population-a combined quantitative and qualitative classification system analysis.
abstract: OBJECTIVE
  The aim of this study was to explore the dental functional status of a Southern Vietnamese adult population using a new quantitative- and qualitative-based classification system.
  
  
  METHODS
  The sample consisted of 2,809 dentate subjects aged ⋝ 20 years from urban and rural areas of Southern Vietnam. Dentitions were classified by a dichotomized five-level step-by-step branching hierarchy reflecting functionality. Cut-offs were as follows: level I (dentition level) = 1 tooth present in each arch, level II (arch level) = 10 teeth in each arch, level III (anterior region) = all 12 anterior teeth present, level IV (premolar region) = ⋝ 3 premolar posterior opposing pairs (POPs) present, and level V (molar region) = 1 molar POP bilaterally.
  
  
  RESULTS
  Of the 2,809 subjects, 44% met all criteria for a functional dentition and 16% met none. Of subjects meeting level II, 81% had a complete anterior region, 74% had a sufficient premolar region, and 66% had a sufficient molar region. For subjects not meeting level II, these figures were 9%, 15%, and 8%, respectively. For patients meeting level II who were between 20 and 35 years of age, a mean 29.2 ± 2.4 teeth and 7.9 ± 2.1 POPs were present; subjects 65 years of age and older had a mean 25.6 ± 3.2 teeth and 5.9 ± 2.1 POPs. For patients not meeting level II, these numbers were 18.6 ± 2.9 teeth and 3.1 ± 1.8 POPs and 12.8 ± 5.4 teeth and 0.9 ± 1.4 POPs for 20- to 35-year-olds and those 65 years of age and older, respectively. Intraclass correlation coefficients for number of teeth and POPs showed fair to good group homogeneities.
  
  
  CONCLUSIONS
  The World Health Organization goal of retaining at least 20 teeth throughout life is not achieved in Southern Vietnam; above the age of 44, less than 75% of subjects presented with 20 or more teeth. The presented classification system is a useful framework for mapping the functionality of dentitions by applying additional criteria for dental regions.
authors.affiliation: Department of Prosthodontics, Can Tho University of Medicine and Pharmcay, Can Tho, Vietnam.
authors.forename: Thoa C
authors.initials: TC
authors.lastname: Nguyen
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Witter
authors.forename: Ewald M
authors.initials: EM
authors.lastname: Bronkhorst
authors.forename: Luc H
authors.initials: LH
authors.lastname: Pham
authors.forename: Nico H J
authors.initials: NH
authors.lastname: Creugers
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001641:Bicuspid / Q000473:pathology; D003430:Cross-Sectional Studies; D003481:Cuspid / Q000473:pathology; D003817:Dentition; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D007180:Incisor / Q000473:pathology; D007576:Jaw, Edentulous, Partially / Q000145:classification / Q000453:epidemiology*; D008297:Male; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D008875:Middle Aged; D008963:Molar / Q000473:pathology; D012423:Rural Health / Q000706:statistics & numerical data; D016388:Tooth Loss / Q000145:classification / Q000453:epidemiology; D014504:Urban Health / Q000706:statistics & numerical data; D014744:Vietnam / Q000453:epidemiology; D055815:Young Adult