Influence of residual pockets on progression of periodontitis and tooth loss: results after 11 years of maintenance

J Clin Periodontol. 2008 Aug;35(8):685-95. doi: 10.1111/j.1600-051X.2008.01245.x. Epub 2008 Jul 23.


Background: Limited evidence exists on the significance of residual probing pocket depth (PPD) as a predictive parameter for periodontal disease progression and tooth loss.

Aim: The aim of this study was to investigate the influence of residual PPD >or=5 mm and bleeding on probing (BOP) after active periodontal therapy (APT) on the progression of periodontitis and tooth loss.

Material and methods: In this retrospective cohort, 172 patients were examined after APT and supportive periodontal therapy (SPT) for 3-27 years (mean 11.3 years). Analyses were conducted using information at site, tooth and patient levels. The association of risk factors with tooth loss and progression of periodontitis was investigated using multilevel logistic regression analysis.

Results: The number of residual PPD increased during SPT. Compared with PPD<or=3 mm, PPD=5 mm represented a risk factor for tooth loss with odds ratios of 5.8 and 7.7, respectively, at site and tooth levels. The corresponding odds ratios for PPD=6 mm were 9.3 and 11.0 and for PPD>or=7 mm 37.9 and 64.2, respectively. At patient level, heavy smoking, initial diagnosis, duration of SPT and PPD>or=6 mm were risk factors for disease progression, while PPD>or=6 mm and BOP>or=30% represented a risk for tooth loss.

Conclusion: Residual PPD>or=6 mm represent an incomplete periodontal treatment outcome and require further therapy.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Cohort Studies
  • Disease Progression
  • Female
  • Follow-Up Studies
  • Forecasting
  • Furcation Defects / physiopathology
  • Gingival Hemorrhage / physiopathology
  • Gingival Recession / physiopathology
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Periodontal Attachment Loss / physiopathology
  • Periodontal Pocket / physiopathology*
  • Periodontal Pocket / therapy
  • Periodontitis / physiopathology*
  • Retrospective Studies
  • Risk Factors
  • Smoking / physiopathology
  • Tooth Loss / physiopathology*
  • Tooth Mobility / physiopathology
  • Treatment Outcome