Bacteremia due to periodontal probing: a clinical and microbiological investigation

Infective endocarditis can occur in susceptible individuals due to bacteremia of oral origin. The aim of this study was to investigate the occurrence of bacteremia caused by full mouth periodontal probing.

Forty patients, 20 with adult periodontitis (10 males, 10 females; mean age 43.0 years) and 20 with chronic gingivitis (11 males, 9 females; mean age 35.5 years) were investigated. Prior to and immediately following periodontal probing, 20 mL of venous blood were obtained from each patient and inoculated into aerobic and anaerobic blood culture bottles and incubated. Negative bottles were monitored continuously for 3 weeks before being discarded. Bottles which signalled positive were subcultured and isolates identified to genus level. Periodontal probing consisted of measuring pockets at 6 points around each tooth and recording the presence or absence of bleeding. A plaque index (PI) was assessed on the 6 Ramfjord teeth.

Probing caused bacteremia of oral origin in 8 (40%) of the periodontitis patients and 2 (10%) of the gingivitis patients. Streptococcus spp. were the most common isolates in both groups. Compared with the gingivitis group the odds ratio (OR) for bacteremia in the periodontitis group was 5.993 (95% CI 1.081 to 33.215). Bleeding on probing (OR 1.025, 95% CI 1.004 to 1.047) and mean probing depth per tooth (OR 1.444, 95% CI 1.055 to 1.977) were significantly associated with bacteremia. No significant correlations were found between bacteremia and age, number of teeth probed, smoking status, PI, or total probing depth.

Patients with untreated adult periodontitis are at greater risk of bacteremia due to periodontal probing than patients with chronic gingivitis. For individuals at risk of infective endocarditis, radiographic assessment prior to periodontal probing would be advisable to identify those with periodontitis so that appropriate antibiotic prophylaxis can be provided.