title: Bleeding on probing as it relates to smoking status in patients enrolled in supportive periodontal therapy for at least 5 years.
abstract: OBJECTIVE
  To relate the mean percentage of bleeding on probing (BOP) to smoking status in patients enrolled in supportive periodontal therapy (SPT).
  
  
  METHODS
  Retrospective data on BOP from 8'741 SPT visits were related to smoking status among categories of both periodontal disease severity and progression (instability) in patients undergoing dental hygiene treatment at the Medi School of Dental Hygiene (MSDH), Bern, Switzerland 1985-2011.
  
  
  RESULTS
  A total of 445 patients were identified with 27.2% (n = 121) being smokers, 27.6% (n = 123) former smokers and 45.2% (n = 201) non-smokers. Mean BOP statistically significantly increased with disease severity (p = 0.0001) and periodontal instability (p = 0.0115) irrespective of the smoking status. Periodontally stable smokers (n = 30) categorized with advanced periodontal disease demonstrated a mean BOP of 16.2% compared to unstable smokers (n = 15) with a mean BOP of 22.4% (p = 0.0291). Assessments of BOP in relation to the percentage of sites with periodontal probing depths (PPD) ≥ 4 mm at patient-level yielded a statistically significantly decreased proportion of BOP in smokers compared to non-smokers and former smokers (p = 0.0137).
  
  
  CONCLUSIONS
  Irrespective of the smoking status, increased mean BOP in SPT patients relates to disease severity and periodontal instability while smokers demonstrate lower mean BOP concomitantly with an increased prevalence of residual PPDs.
authors.affiliation: Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Ramseier
authors.forename: Damiano
authors.initials: D
authors.lastname: Mirra
authors.forename: Christian
authors.initials: C
authors.lastname: Schütz
authors.forename: Anton
authors.initials: A
authors.lastname: Sculean
authors.forename: Niklaus P
authors.initials: NP
authors.lastname: Lang
authors.forename: Clemens
authors.initials: C
authors.lastname: Walter
authors.forename: Giovanni E
authors.initials: GE
authors.lastname: Salvi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D057747:Periodontal Debridement / Q000379:methods; D010510:Periodontal Diseases / Q000145:classification / Q000517:prevention & control*; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000145:classification / Q000517:prevention & control; D012008:Recurrence; D012189:Retrospective Studies; D012907:Smoking; D013997:Time Factors; D055815:Young Adult
keywords: bleeding on probing; cigarette smoking; supportive periodontal therapy