Distribution of Streptococcus mutans and Streptococcus sobrinus at sub-sites in human approximal dental plaque.
The distribution and prevalence of Streptococcus mutans and Streptococcus sobrinus were determined at three sub-sites in human approximal plaque: away from (A), to the side of (S) and below (B) the contact area. Small plaque samples were taken from all three sub-sites on clinically sound approximal surfaces of a single premolar from each of 21 schoolchildren. S. mutans was detected significantly more often and in higher proportions than S. sobrinus from sub-sites A (p = 0.019), S (p = 0.034) and B (p = 0.004). S. mutans was detected in highest proportions from the B site compared to the A site (p = 0.025); there were no significant differences in the isolation frequency or prevalence of S. sobrinus from any of the sub-sites. S. mutans and S. sobrinus were never isolated together from the A sub-sites and were recovered together most commonly from the B sub-sites (p < 0.01). It is concluded that S. mutans and S. sobrinus preferentially colonise the most caries-prone site apical to the contact area.
Ahmady
K
K
Department of Periodontology, University of London, UK.
Marsh
P D
PD
Newman
H N
HN
Bulman
J S
JS
D001421:Bacteria, Anaerobic / Q000302:isolation & purification; D001641:Bicuspid / Q000382:microbiology; D002648:Child; D015169:Colony Count, Microbial; D003773:Dental Plaque / Q000382:microbiology*; D004463:Ecology; D005260:Female; D006801:Humans; D008297:Male; D013295:Streptococcus mutans / Q000302:isolation & purification*; D016986:Streptococcus sobrinus / Q000302:isolation & purification*