title: 2-year observation of attachment loss in a rural Chinese population.
abstract: BACKGROUND
  Risk indicators for periodontitis seem to vary with study population. The purpose of this study was to determine whether risk indicators of additional attachment loss differ between generations of Chinese villagers in a rural area of China over a 2-year period.
  
  
  METHODS
  The study population consisted of 310 subjects aged 15 to 44. In each subject, 2 quadrants from either the upper or lower jaw were randomly selected and 6 sites on each tooth were examined. Clinical parameters included plaque scoring system (PSS), calculus index (CI), probing depth (PD), attachment level (AL), and sulcus bleeding index (SBI). The second examination was done 2 years after the first.
  
  
  RESULTS
  In the 15- to 24-year-old age group, mean PSS, CI, and SBI were significantly higher in subjects with additional attachment loss > or =3 mm (AL+) than in those without attachment loss (AL-). In the 25- to 34-year-old age group, mean PD was significantly higher in AL+ than in AL-, and mean PD and AL were significantly higher in AL+ than in AL- in the 35- to 44-year-old age group. Although the number of subjects with AL+ increased with age, the mean number of sites with AL+ per subject did not differ by generation. In addition, smokers tended to exhibit attachment loss more often than non-smokers.
  
  
  CONCLUSIONS
  The present results suggest that the clinical parameters associated with attachment loss differ between generations and that gingival inflammation is likely associated with the onset of periodontitis more strongly than progression of periodontitis, whereas PD and/or AL are associated with the progression of periodontitis.
authors.affiliation: Department of Periodontics, Showa University Dental School, Tokyo, Japan. okiers@aol.com
authors.forename: R
authors.initials: R
authors.lastname: Suda
authors.forename: C
authors.initials: C
authors.lastname: Cao
authors.forename: K
authors.initials: K
authors.lastname: Hasegawa
authors.forename: S
authors.initials: S
authors.lastname: Yang
authors.forename: R
authors.initials: R
authors.lastname: Sasa
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002681:China / Q000453:epidemiology; D015988:Cohort Effect; D015331:Cohort Studies; D003774:Dental Plaque Index; D018450:Disease Progression; D006801:Humans; D015994:Incidence; D009911:Oral Hygiene Index; D017622:Periodontal Attachment Loss / Q000453:epidemiology* / Q000209:etiology*; D010512:Periodontal Index; D012307:Risk Factors; D012423:Rural Health / Q000706:statistics & numerical data*; D012907:Smoking / Q000009:adverse effects; D012959:Socioeconomic Factors; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires