title: Trends of periodontal conditions in two different randomly selected Swiss (Bernese) cohorts 25 years apart.
abstract: OBJECTIVE
  To assess the periodontal conditions of two randomly selected Swiss cohorts 25 years apart.
  
  
  METHODS
  Standardized examinations were performed to assess the periodontal conditions of two randomly selected populations of the Canton of Bern; oral cleanliness was evaluated using the plaque index (PlI) and the retention index (RI). Gingival health was scored according to the gingival index (GI). Periodontal conditions were evaluated by pocket probing depth (PPD) and loss of attachment (LA).
  
  
  RESULTS
  At the first examination in 1985, 206 out of 350 subjects were evaluated, while in the second examination in 2010, 134 out of 490 subjects attended the examinations. In 1985, subjects showed a mean PlI of 1.16, and 0.77 in 2010. RI was 0.81 and 0.36 in 1985 and 2010 respectively. Mean GI was 1.34 and 0.6. The mean proportion of PPD ≤3 mm was 72% in 1985 and 97.3% in 2010. PPD ≥ 6 mm affected 2.0% in 1985 and 0.3% in 2010. In 1985, subjects had an average of 20.7 teeth, while in 2010, the average was 24.6. In 1985, 7.3% of the subjects were edentulous, while in 2010, 4.5% had no teeth.
  
  
  CONCLUSIONS
  Trends to improvements resulting in more teeth in function and better periodontal conditions were recognized.
authors.affiliation: School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Ernst
authors.initials: E
authors.lastname: Schürch
authors.affiliation: School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Joëlle A
authors.initials: JA
authors.lastname: Dulla
authors.affiliation: School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Walter
authors.initials: W
authors.lastname: Bürgin
authors.affiliation: School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Adrian
authors.initials: A
authors.lastname: Lussi
authors.affiliation: School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Niklaus P
authors.initials: NP
authors.lastname: Lang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003774:Dental Plaque Index; D005260:Female; D005881:Gingiva; D006801:Humans; D008297:Male; D008875:Middle Aged; D010510:Periodontal Diseases; D010512:Periodontal Index; D010514:Periodontal Pocket; D055815:Young Adult
keywords: Switzerland; epidemiology; oral hygiene status; periodontitis; probing depth; tooth loss