Bacteraemia due to dental flossing

J Clin Periodontol. 2009 Apr;36(4):323-32. doi: 10.1111/j.1600-051X.2008.01372.x. Epub 2009 Mar 11.


Aims: The aims of this study were to (1) investigate the incidence of bacteraemia following flossing in subjects with chronic periodontitis or periodontal health; (2) identify the micro-organisms in detected bacteraemias; and (3) identify any patient or clinical factors associated with such bacteraemia.

Material and methods: Baseline blood samples were obtained from 30 individuals with chronic periodontitis (17 M:13 F, 29-75 years) and 30 with periodontal health (17 M:13 F, 28-71 years) following a non-invasive examination. Each subject's teeth were then flossed in a standardized manner and blood samples obtained 30 s and 10 min. after flossing cessation. Blood samples were cultured in a BACTEC system and positive samples subcultured for identification.

Results: Forty per cent of periodontitis subjects and 41% of periodontally healthy subjects tested positive for bacteraemia following flossing. Viridans streptococci, which are commonly implicated in infective endocarditis (IE), were isolated from 19% of positive subjects and accounted for 35% of microbial isolates. Twenty per cent of subjects had a detectable bacteraemia at 10 min. post-flossing. No patient or clinical factors were significantly associated with post-flossing bacteraemia.

Conclusions: Dental flossing can produce bacteraemia in periodontally healthy and periodontally diseased individuals at a rate comparable with that caused by some dental treatments for which antibiotic prophylaxis is given to prevent IE.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibiotic Prophylaxis / statistics & numerical data
  • Bacteremia / etiology*
  • Bacteremia / microbiology
  • Case-Control Studies
  • Chronic Periodontitis / therapy*
  • Dental Devices, Home Care / adverse effects*
  • Dental Plaque Index
  • Dental Prophylaxis / adverse effects*
  • Dental Prophylaxis / instrumentation
  • Female
  • Humans
  • Male
  • Middle Aged
  • Periodontal Index
  • Periodontitis / prevention & control
  • Reproducibility of Results
  • Viridans Streptococci / isolation & purification