title: Trends over 30 years in the prevalence and severity of alveolar bone loss and the influence of smoking and socio-economic factors--based on epidemiological surveys in Sweden 1983-2013.
abstract: OBJECTIVE
  Epidemiological studies of the prevalence of periodontitis over an extended time using the same methodology to investigate and classify periodontitis are sparse in the literature. Smoking and socio-economic factors have been proven to increase the risk for periodontal disease. The objective of this study was to investigate 30-year time trends, using the same methodology to classify the prevalence and severity in alveolar bone loss (ABL) and to investigate the influence of tobacco and socio-economic factors.
  
  
  METHODS
  Four cross-sectional epidemiological studies in an adult population were performed in the county of Dalarna, Sweden, in 1983, 2003, 2008 and 2013. Random samples of 787-1133 individuals aged 35-85 who answered a questionnaire about tobacco use and socio-economic factors were radiographically and clinically examined. A number of teeth, ABL and calculus visible on radiographs were registered. The severity of ABL as detected on radiographs was classified into no bone loss, moderate or severe.
  
  
  RESULTS
  The prevalence of moderate ABL decreased from 45% in 1983 to 16% in 2008, but increased to 33% in 2013 (P < 0.05). The prevalence of severe ABL remained the same from 1983 (7%) to 2013 (6%). Calculus visible on radiographs increased from 22% in 2008 to 32% in 2013 (P < 0.05). Socio-economic factors had limited impact on the severity of ABL.
  
  
  CONCLUSIONS
  Moderate ABL and calculus visible on radiographs significantly increased between 2008 and 2013. Smoking was the strongest factor associated with ABL overall.
authors.affiliation: Center for Oral Rehabilitation, Falun, Sweden.|Oral and Maxillofacial Surgery, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Edman
authors.affiliation: School of Health and Social Studies, Dalarna University, Falun, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Öhrn
authors.affiliation: Administrative Center for Public Dental Services, Falun, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Nordström
authors.affiliation: National Dental Service Gävleborg, Center for Clinical Research, Uppsala University/Region Gävleborg, Gävle, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Holmlund
authors.affiliation: Center for Clinical Research, Falun, Sweden.|Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden.
authors.forename: D
authors.initials: D
authors.lastname: Hellberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016301:Alveolar Bone Loss / Q000453:epidemiology* / Q000209:etiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects*; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors
keywords: epidemiology; periodontal disease; smoking