We conducted a study to determine the frequency of bacteraemias following dental extraction and common oral procedures, namely tooth brushing and chewing, and the relationship between bacteraemia and oral health in black patients. Positive blood cultures were detected in 29.6% of patients after dental extraction, in 10.8% of patients after tooth brushing and in no patients after chewing. No relationship between the state of oral health, which was assessed using the plaque and gingival indices, and the incidence of bacteraemia was found. The duration of bacteraemia was less than 15 minutes. One patient had a positive blood culture prior to dental extraction; his oral health status was poor. Our study confirmed that bacteraemia occurs after tooth brushing.

We evaluated some of the regimens recommended for the antimicrobial prophylaxis of infective endocarditis prior to dental extraction in 160 patients. Group A patients served as the control group, group B subjects rinsed their mouths with chlorhexidene, group C subjects took 3 g amoxicillin orally and group D patients took 600 mg clindamycin orally. The proportion of patients who had post-extraction bacteraemia in groups A, B, C and D was 35, 40, 7.5 and 20%, respectively. The differences between the control and amoxicillin groups (p = 0.003) and between the chlorhexidine and amoxicillin groups (p = 0.0006) were statistically significant. Streptococci were not isolated in any patients in the amoxicillin and clindamycin groups. In our study, none of the regimens were effective in preventing post-extraction bacteraemia.

In order to determine whether adequate attention is paid to the maintenance of good oral health in patients at risk of developing infective endocarditis, we studied 44 black patients with severe rheumatic heart disease before they had cardiac surgery. Plaque and gingival index scores were calculated and panoramic radiographs were done in all patients. There were 17 males and 27 females (mean age: 30.6 years). The plaque and gingival index scores were classified as poor in 31.8 and 54.6% of patients, respectively. Panoramic radiographic findings included caries in 56.8% of patients, peri-apical pathology in 18.1% and retained roots in 22.7% of patients. This study demonstrates that inadequate attention is paid to the maintenance of good oral health in patients with severe rheumatic heart disease. The oral and dental care of patients at risk of developing infective endocarditis needs to be improved.