Caries incidence in intact rats infected with Streptococcus sobrinus via transmission from desalivated cagemates.
The purpose of this study was to determine the influence of caging desalivated S. sobrinus-infected rats on the caries incidence in intact, previously uninfected cagemates. Weanlings were divided as follows: Stage I: Twenty desalivated animals paired with 20 intact animals (Group I); 20 intact animals paired with 20 intact animals (Group II). Animals were infected with S. sobrinus and fed diet 2000 and 10% sucrose water. After five weeks, ten paired animals from each group were killed. Desalivated animals had statistically higher (p less than 0.05) caries scores than did other animals. Stage II: The remaining Stage I infected animals from Groups I and II were paired with 40 new uninfected animals 15 days of age and fed cariogenic diets. After five weeks, new intact animals paired with Stage I desalivated animals had significantly higher smooth-surface enamel caries scores (38.0; SE 7.84) than new intact animals paired with Stage I intact animals (11.15; SE 3.69). Moreover, new intact animals caged for only five weeks with Stage I desalivated animals developed smooth-surface caries (38.0; SE 7.84) to a degree comparable with that in all Stage I intact animals in the experiment for ten weeks (36.6, SE 9.5; and 30.05, SE 4.1). The data suggest that desalivation may select a readily transmissible strain of S. sobrinus, which demonstrates enhanced virulence.
Madison
K M
KM
University of Rochester, Department of Dental Research, New York 14642.
Bowen
W H
WH
Pearson
S K
SK
Falany
J L
JL
D000818:Animals; D003731:Dental Caries / Q000382:microbiology*; D004037:Diet, Cariogenic; D005260:Female; D015994:Incidence; D007778:Lactobacillus / Q000302:isolation & purification; D051381:Rats; D011919:Rats, Inbred Strains; D012469:Salivary Glands / Q000601:surgery*; D013290:Streptococcal Infections / Q000635:transmission*; D013291:Streptococcus / Q000302:isolation & purification / Q000472:pathogenicity; D014774:Virulence