title: Tooth loss in compliant and non-compliant periodontally treated patients: 7 years after active periodontal therapy.
abstract: OBJECTIVE
  To investigate the incidence and reasons for tooth loss during active periodontal therapy (APT) and periodontal maintenance (PM) in a specialist institution.
  
  
  METHODS
  Retrospective data were collected from 273 patients [all compliers (AC)] and cross-sectional data from 39 patients after discontinuation of PM [non-compliers (NC)] for at least 7 years after APT. Descriptive statistics and regression analysis were performed. A comparison was made between AC and NC. The prognostic factors associated with tooth loss during PM were identified.
  
  
  RESULTS
  AC lost 1.3 teeth/patient during APT and 0.9 teeth/patient during PM (mean 10.7 years). Tooth loss due to periodontitis was 0.03 teeth/patient/year. The age of 60 was a significant predictor of tooth loss during PM (odds ratio of 2.1). NC lost 1.1 teeth/patient during APT and 2.7 teeth/patient during discontinuation (mean 9.6 years). Tooth loss due to periodontitis was 0.22 teeth/patient/year, a sevenfold increase (p<0.05) compared with AC. Regression analysis failed to identify any significant predictors for tooth loss during the discontinuation of PM.
  
  
  CONCLUSIONS
  In this study, the provision of PM led to minimal tooth loss, especially due to periodontitis, for a mean period of 10 years after APT. The completion of APT without PM may predispose patients to lose more teeth compared with patients who undergo PM.
authors.affiliation: Department of Restorative Dentistry, National Dental Centre Singapore, Singapore. mervyn_ng@yahoo.com
authors.forename: Mervyn Cher-Hui
authors.initials: MC
authors.lastname: Ng
authors.forename: Marianne Meng-Ann
authors.initials: MM
authors.lastname: Ong
authors.forename: Lum Peng
authors.initials: LP
authors.lastname: Lim
authors.forename: Chu Guan
authors.initials: CG
authors.lastname: Koh
authors.forename: Yiong Huak
authors.initials: YH
authors.lastname: Chan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055113:Chronic Periodontitis / Q000150:complications* / Q000628:therapy; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009910:Oral Hygiene / Q000706:statistics & numerical data*; D010349:Patient Compliance; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D016388:Tooth Loss / Q000150:complications* / Q000517:prevention & control; D016896:Treatment Outcome; D055815:Young Adult