title: Prevalence and extent of lifetime cumulative attachment loss (LCAL) at different thresholds and associations with clinical variables: changes in a population of young male military recruits over 3 years.
abstract: OBJECTIVE
  The aims of this study were to monitor the prevalence and progression of lifetime cumulative attachment loss (LCAL) in a group of young British male military recruits over a 3-year period, and to determine the relationship between signs of LCAL and selected periodontal variables.
  
  
  METHODS
  100 subjects, aged 16-20 years (mean 17 years) at baseline, were examined at 0 (baseline), 12 and 30 months. LCAL, probing depth, plaque, bleeding on probing, gingival colour and supra- and subgingival calculus were assessed on the mesio-buccal, disto-buccal, mesio-lingual and disto-lingual surfaces of all teeth present, excluding third molars. Data were analysed cross-sectionally at each examination.
  
  
  RESULTS
  Over the period of the study, the prevalence of LCAL > or =1 and 2 mm ranged from 95-100%, whereas LCAL > or =3 mm ranged from 40-47%. The extent of LCAL > or =1 mm ranged from 76-86%. However, the extent of LCAL > or =2 mm was dramatically lower (10.5-12.7%), and LCAL > or =3 mm was uncommon (0.5-0.9%). Examining the number of subjects according to the number of sites affected above a threshold, showed that a small number of subjects have a large number of sites above threshold. Using Pearson's rank correlation coefficient a significant correlation (p<0.05) was found between LCAL and the periodontal variables of gingival bleeding and supra- and subgingival calculus.
  
  
  CONCLUSIONS
  These data suggest that the onset and progression of chronic periodontitis can be seen in young adults, and in this group gingival bleeding and supra- and subgingival calculus are the variables most strongly associated with early periodontitis.
authors.affiliation: Department of Periodontology, Eastman Dental Institute and Hospital for Oral Health Care Sciences, University College London, London, UK. g.griffiths@eastman.ucl.ac.uk
authors.forename: G S
authors.initials: GS
authors.lastname: Griffiths
authors.forename: S
authors.initials: S
authors.lastname: Duffy
authors.forename: K A
authors.initials: KA
authors.lastname: Eaton
authors.forename: M S
authors.initials: MS
authors.lastname: Gilthorpe
authors.forename: N W
authors.initials: NW
authors.lastname: Johnson
mesh_terms: D000206:Actuarial Analysis; D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D003430:Cross-Sectional Studies; D003728:Dental Calculus / Q000473:pathology; D003774:Dental Plaque Index; D006285:Health Planning; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008889:Military Personnel; D017622:Periodontal Attachment Loss / Q000453:epidemiology* / Q000473:pathology*; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000473:pathology; D010518:Periodontitis / Q000453:epidemiology; D015995:Prevalence; D015203:Reproducibility of Results; D012307:Risk Factors; D018709:Statistics, Nonparametric