title: Relationship between the prognosis of periodontitis and occlusal force during the maintenance phase--a cohort study.
abstract: OBJECTIVE
  Few studies have longitudinally investigated the relationship between periodontal disease progression and occlusal factors in individual subjects during the maintenance phase of periodontal therapy. The aim of this cohort study was to investigate the relationship between biting ability and the progression of periodontal disease in the maintenance phase.
  
  
  METHODS
  A total of 194 patients were monitored for 3 years during the maintenance phase of periodontal therapy. The subjects with disease progression (Progress group) were defined based on the presence of >or= 2 teeth demonstrating a longitudinal loss of proximal attachment of >or= 3 mm or tooth-loss experience as a result of periodontal disease during the study period. The subjects with high occlusal force were diagnosed as men who showed an occlusal force of more than 500 N and women who showed an occlusal force of more than 370 N. The association between biting ability and the progression of periodontitis was investigated using logistic regression analysis.
  
  
  RESULTS
  There were 83 subjects in the Progress group and 111 subjects in the Non-progress group. A backward, stepwise logistic regression model showed that the progression of periodontal disease was significantly associated with the presence of one or more teeth with a high clinical attachment level (CAL) of >or= 7 mm (odds ratio: 2.397; 95% confidence interval: 1.306-4.399) ( p = 0.005) and low occlusal force (odds ratio: 2.352; 95% confidence interval: 1.273-4.346) ( p = 0.006).
  
  
  CONCLUSIONS
  The presence of one or more teeth with a high CAL of >or= 7 mm and low occlusal force might be possible risk factors for periodontal progression in the maintenance phase of periodontal therapy.
authors.affiliation: Department of Preventive Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Shikata-cho, Kita-ku, Okayama, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Takeuchi
authors.forename: D
authors.initials: D
authors.lastname: Ekuni
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: M
authors.initials: M
authors.lastname: Morita
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001732:Bite Force; D055113:Chronic Periodontitis / Q000503:physiopathology* / Q000628:therapy; D015331:Cohort Studies; D003777:Dental Prophylaxis; D018450:Disease Progression; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D017622:Periodontal Attachment Loss / Q000503:physiopathology; D010512:Periodontal Index; D011379:Prognosis; D012307:Risk Factors; D018709:Statistics, Nonparametric