Cariogenic Bacteria in a Longitudinal Study of Approximal Caries

Abstract

Two hundred and seventeen approximal spaces, initially caries free, in 58 patients were studied clinically and radiographically, at intervals of 6 months, for 3 years. Samples of approximal dental plaque were removed for culture of Streptococcus mutans, Streptococcus sobrinus, and lactobacilli. During the study approximal caries developed in 16 subjects (27.6%) at 30 sites (13.8%), involving 42 teeth. 56 of 58 (96.7%) subjects harboured S. mutans at some time during the study, 62.1% lactobacilli, and 29.3% had S. sobrinus. The counts of S. mutans were significantly higher in those subjects that also carried S. sobrinus than in the remaining subjects. A persisting high count of S. mutans > 105 colony-forming units per millilitre (CFU/ml) or a count that rose by ≥ 1 × log10 CFU/ml during the study was seen in 25 of 30 sites that subsequently became carious (p < 0.001). Similarly, counts of lactobacilli that were consistently > 103 CFU/ml or rising by ≥l×logo CFU/ml were seen in 17 of 30 sites that became carious (p < 0.001). Although there were strong statistical associations between approximal caries and high or rising counts of these cariogenic bacteria, the bacterial counts were not good predictors of future approximal caries at that particular site.

Studies on strains ofStreptococcus mutansisolated from caries-active and caries-free individuals in Iceland

“…Strains of S. mutans were collected regularly from subjects of different ages from 4 years up to adulthood as part of one of a number of research projects aimed at assessing caries risk (15, 16, 18, 20). Ethical permission for each study was obtained from the relevant authority in Iceland as appropriate.…”

“…The prevalence of caries was higher than in other Nordic countries (11) and the decline in caries recorded in N. America, Europe and elsewhere in the latter part of the 20th century did not occur in Iceland until later and, according to the latest surveys, caries prevalence seems to have risen again (12). A number of studies of mutans streptococci have been carried out in Iceland that have served to confirm a number of conclusions that fit with the specific plaque hypothesis (13–16). Interestingly, one longitudinal study of the development of approximal caries on originally healthy approximal tooth surfaces showed that S. mutans sometimes only appeared on the particular approximal tooth surface after the development of caries as detected radiographically.…”

“…Interestingly, one longitudinal study of the development of approximal caries on originally healthy approximal tooth surfaces showed that S. mutans sometimes only appeared on the particular approximal tooth surface after the development of caries as detected radiographically. In all cases the count of S. mutans increased following the onset of caries (16). …”

Ecological Study of Streptococcus mutans, Streptococcus sobrinus and Lactobacillus spp. at Sub-Sites from Approximal Dental Plaque from Children

“…They found 100-fold differences in the concentration of S. mutans in samples taken from a single white spot lesion compared to those from adjacent healthy enamel. Many studies have shown a correlation between plaque counts of MS and both caries prevalence and incidence [Loesche, 1986;Lang et al, 1987;Crossner et al, 1989;Beighton et al, 1989;Sigurjons et al, 1995]. However, there have also been investigations that found no correlation between the MS count and the presence of caries [Hardie et al, 1977;Carlsson et al, 1985;Marsh et al, 1989b;Macpherson et al, 1992].…”

Die Bedeutung der Ernährung für die orale Gesundheit

“…In der kariösen Plaque spielen besonders Streptococcus mutans und Streptococcus sobrinus, aber auch Laktobazillen und Aktinomyzeten eine entscheidende Rolle [26]. Wichtige protektive Faktoren sind der Speichel (Spülfunktion, Neutralisierung des pH-Wertes), die Zahnreinigung und die Aufnahme von Fluorid.…”