title: Changing oral health status of 6- and 12-year-old schoolchildren in Portugal.
abstract: OBJECTIVE
  To assess the actual oral health status of Portuguese schoolchildren aged 6 and 12 years according to gender and urbanisation, to highlight the trend over time in dental caries prevalence of children, to assess the dental care habits and the provision of preventive services to children, and to analyse the effect of dental care habits on caries experience.
  
  
  METHODS
  Clinical examinations of oral health status were carried out in 1999 according to WHO criteria and included dental caries, enamel lesions, oral hygiene status (OHI-S) and Community Periodontal Index (CPI). Structured questionnaires for interviewing children on dental care habits and participation in preventive programmes at school were used. The study comprised 799 6 year olds and 800 12 year olds.
  
  
  RESULTS
  In 1999, the prevalence proportion rates of dental caries were 46.9% in 6 year olds and 52.9% in 12 year olds. Dental caries experience was 2.1 dmf-t and 1.5 DMF-T, respectively. Significant reductions in caries prevalence rates took place over time; in 1984 the mean dmf-t of 6 year olds was 5.2 and for 12 year olds it was 3.7 DMF-T. Enamel opacities were found for 7.2% of children and 2.1% had moderate dental fluorosis. At age 12, 90% of children had poor oral hygiene, i.e. CPI Score 2 (bleeding and calculus). Toothbrushing twice a day was reported for 31% of 6-year-olds and 55.6% of 12-year-olds; 17.8% of children aged 6 had seen a dentist during the past year and this was found to be 58.3% at age 12. Substantial proportions of the children received preventive dental services in school. Multivariate analysis of dental caries experience showed that gender, location, nationality, dental visits and frequency of toothbrushing were significant independent variables.
  
  
  CONCLUSIONS
  Further implementation of school based oral health promotion and application of population-directed preventive strategies are needed in Portugal.
authors.affiliation: Department for Community Dental Health, Faculty of Dental Medicine, University of Lisbon, Portugal.
authors.forename: César Mexia
authors.initials: CM
authors.lastname: de Almeida
authors.forename: Poul Erik
authors.initials: PE
authors.lastname: Petersen
authors.forename: Sónia Jesus
authors.initials: SJ
authors.lastname: André
authors.forename: António
authors.initials: A
authors.lastname: Toscano
mesh_terms: D000704:Analysis of Variance; D002648:Child; D004245:DMF Index; D003729:Dental Care / Q000706:statistics & numerical data; D003731:Dental Caries / Q000453:epidemiology* / Q000517:prevention & control*; D003744:Dental Enamel Hypoplasia / Q000453:epidemiology; D005260:Female; D009050:Fluorosis, Dental / Q000453:epidemiology; D005891:Gingivitis / Q000453:epidemiology; D006801:Humans; D016014:Linear Models; D008297:Male; D009909:Oral Health; D009910:Oral Hygiene / Q000706:statistics & numerical data*; D009911:Oral Hygiene Index; D011174:Portugal / Q000453:epidemiology; D015995:Prevalence; D015397:Program Evaluation; D012571:School Dentistry; D014504:Urban Health