title: Prevalence of bleeding on probing: a cohort study in a specialist periodontal clinic.
abstract: OBJECTIVE
  to assess the prevalence and distribution of bleeding on probing (BoP) in a cohort of periodontally diseased patients, evaluate the influence of patient-related predictors on BoP variability, and characterize two subgroups of patients with a significantly different BoP score.
  
  
  METHODS
  six hundred and one patients were retrospectively included. The percentage of BoP-positive sites was calculated for the entire dentition (%BoPtotal) and within different areas of the dentition. The influence of patient-related predictors on intersubject variability in %BoPtotal was evaluated. Two subgroups of patients, belonging to the lowest (LB, low bleeding) and highest (high bleeding, HB) quartile of patient distribution according to %BoPtotal, were identified.
  
  
  RESULTS
  median %BoPtotal was 26.4%, with 99% of the population showing at least one BoP-positive site. %BoPtotal was positively correlated with patient age and number of sites with pocket probing depth (PPD) ⋝ 5 mm, and significantly more prevalent in mandibular vs maxillary sites, posterior vs anterior sites, interproximal vs oral/buccal sites, and sites with PPD ⋝ 5 mm vs PPD ⋜ 4 mm. LB and HB patients were significantly different for %BoPtotal, as well as in sites with PPD ⋜ 4 mm and PPD ⋝ 5 mm, but not for sex, age, smoking status, daily cigarette consumption, diabetic status, and number of sites with PPD ⋝ 5 mm.
  
  
  CONCLUSIONS
  BoP was highly prevalent and variable in both patients and different areas of the dentition; patient-related factors and site-specific characteristics (such as age, number of periodontal pockets, probing depth, tooth type, and aspects) seem to be partly responsible for the individual variation in BoP; and HB and LB were not significantly different with respect to the investigated predictors.
authors.affiliation: Research Center for the Study of periodontal and Peri-Implant Diseases, University of Ferrara, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Farina
authors.forename: Chiara
authors.initials: C
authors.lastname: Scapoli
authors.forename: Alberto
authors.initials: A
authors.lastname: Carrieri
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Guarnelli
authors.forename: Leonardo
authors.initials: L
authors.lastname: Trombelli
mesh_terms: D000328:Adult; D000367:Age Factors; D016009:Chi-Square Distribution; D015331:Cohort Studies; D003740:Dental Clinics; D003920:Diabetes Mellitus; D005260:Female; D005891:Gingivitis / Q000453:epidemiology* / Q000473:pathology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000473:pathology*; D010517:Periodontics / Q000295:instrumentation; D010518:Periodontitis / Q000175:diagnosis; D011237:Predictive Value of Tests; D015995:Prevalence; D012189:Retrospective Studies; D015983:Selection Bias; D012737:Sex Factors; D012907:Smoking; D018709:Statistics, Nonparametric; D055815:Young Adult