CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 6, July 2012
340
AFRICA
An investigation of the frequency of bacteraemia
following dental extraction, tooth brushing and chewing
BREMINAND MAHARAJ, YACOOB COOVADIA, AHMED C VAYEJ
Abstract
We conducted a study to determine the frequency of bacte-
raemias following dental extraction and common oral proce-
dures, namely tooth brushing and chewing, and the relation-
ship 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 bacte-
raemia 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.
Keywords:
bacteraemia following dental procedures
Submitted 30/11/11, accepted 24/2/12
Cardiovasc J Afr
2012;
23
: 340–344
DOI: 10.5830/CVJA-2012-016
Dental treatment has been regarded as a major cause of
infective endocarditis, mainly because of the high frequency of
bacteraemia after various oral procedures and the high recovery
rate of viridans streptococci from the blood of patients with
infective endocarditis.
1-3
Awareness of the relationship between
infective endocarditis and dental extraction dates back to 1909,
when Horder noted the association between
Streptococcus
viridans
in the oral cavity and infective endocarditis in patients
with heart disease.
4
Bacteria may invade the bloodstream after a wide variety of
clinical procedures.
5
Lewis and Grant postulated that healthy
persons frequently have innocuous, transient bacteraemia
and that the defective heart valve may trap and retain these
organisms, resulting in infective endocarditis.
6
Okell and Elliot
noted streptococcal bacteraemia following dental extraction in
61% of their patients.
7
Many investigators have assessed the incidence of transient
bacteraemia following various oral procedures. The frequency
of positive blood cultures has ranged from zero to 85% (mean:
40%) for dental extraction, from eight to 79% (mean: 35%) for
dental scaling, from 36 to 88% (mean: 58%) for periodontal
surgery, from seven to 50% (mean: 25%) for tooth brushing or
irrigation, and from zero to 51% (mean: 38%) for chewing.
5,8
Bacteraemia has been detected following flossing,
9
procedures
used for conservative dentistry,
2
intra-oral suture removal,
10
and
endodontic treatment.
11
Although viridans streptococci are the micro-organisms most
frequently isolated in these studies, considerable differences in
frequency, type and magnitude (colony counts per millimetre
of blood) of post-procedure bacteraemia have been reported.
This is mainly the result of diversities in the type of surgical
procedures (e.g. single vs multiple dental extraction), time of
blood sampling, volume of blood cultured, and the methods used
to isolate and identify the micro-organisms, which hinder the
interpretation and comparison of results. The reports published
before the 1960s may also have underestimated the incidence
of transient bacteraemia, since no refined anaerobic culture
techniques were available.
12
Because some of the earlier investigations on antibiotic
prophylaxis had failed to show eradication of bacteria, and the
state of oral health had not been controlled in these studies,
13,14
we decided that it would be important to rule out the possible
influence of oral health on post-extraction bacteraemia. Also,
the frequency of bacteraemia following other common oral
procedures, which have been recorded to produce bacteraemia,
had not been evaluated in black patients.
This study was designed to determine:
•
the relative frequency of bacteraemia following tooth extrac-
tion, tooth brushing and chewing in black patients
•
whether the state of oral health influenced the occurrence of
bacteraemia after these procedures
•
the duration of bacteraemia after these procedures.
Methods
Adult black patients attending the Dassenhoek Dental Clinic
in Marianhill near Durban were included in the study, after
informed consent had been obtained. They were healthy, had no
history of cardiovascular disease and had not received antibiotics
in the previous two weeks.
Any patient found to have a dental abscess was excluded.
In addition, in the extraction part of the study, any patient
who needed more than one tooth extracted or required general
anaesthesia was excluded.
The age and gender of each patient was recorded. The
oral health status was evaluated by clinical examination and
calculation of the plaque and gingival index scores, and rated as
excellent, good, average and poor in each patient.
15,16
One dental
surgeon performed the oral health status evaluation throughout
the study.
This study was approved by the Ethics Committee of the
Nelson R Mandela School of Medicine, University of Natal.
Department of Therapeutics and Medicines Management,
University of KwaZulu-Natal, Durban, South Africa
BREMINAND MAHARAJ, MB ChB, FCP (SA), MD, PhD, FRCP
(London),
Department of Medical Microbiology, University of KwaZulu-
Natal, Durban, South Africa
YACOOB COOVADIA, MB ChB, FCPath (Micro)
Programme: Oral Health, Department of Health, KwaZulu-
Natal, Durban, South Africa
AHMED C VAYEJ, BDS
