Abstract
In many animal models for the study of dental caries, caries is induced by exogenous inoculation with cariogenic bacteria such as Streptococcus mutans. However, it is important to establish a caries model without inoculation, because dental caries is an endogenous infectious disease. Previously we showed that ICR, C57BL/6N, C3H/HeN, and BALB/cA mice fed on a caries-promoting diet, Diet-2000, for 3 months developed fissure caries without prior inoculation. This study was to determine the details of the formation of these carious lesions in C57BL/6N mice. The results were as follows.
1) All experimental groups (Diet-2000 containing 56%, 30%, 10%, and 0% sucrose) developed fissure caries. Sucrose in the diet influenced the progress of caries rather than the caries incidence.
2) Fissure caries developed after only 4 weeks in mice fed on Diet-2000 containing 30% sucrose. The extent of the caries increased with the experimental period.
3) Three- to 4-week-old mice developed the fissure caries effectively. Older mice showed less susceptibility to caries.
This experimental system is suitable model for the study of dental caries as an endogenous infectious disease, and can be used for gaining knowledge of caries etiology, immunology, genetics, and prevention.
