Immunologic Aspect of Mice (Mus musculus) Dental Caries Induced by Streptococcus mutans

Abstract

Dental caries (tooth decay), cavities or caries is a breakdown of teeth due to activities of bacteria acid producing in the presence of fermentable carbohydrates. The most responsible bacteria for dental cavities are Streptococcus mutans. Dental shape, saliva pH, normal flora, diets were suggested as predisposition factors for dental plaque and caries. The aim of this research was to study immunologic response in dental caries induced by S. mutans. This research was experimental study, using post-test control and complete random design. Eighteen mice (Mus musculus) with 18 weeks age, 20-30 gr. body weight, were divided into 2 groups: Infected group and negative control. In the infected group, the mice were given cariogenic food (plus 5% sucrose) and infected by S. mutans (3×10⁵cfu/mL). S. mutans was inoculated onto the enamel and between the teeth. On the 4th day after infection, the mice were euthanized and parotid glands were removed for immunologic examinations (TNF-α, TLR3, TLR4, IL-10, IgA, IFN-γ) and measured by flow cytometry. The data were analysed using one-way ANOVA, α = 0.05. The results showed that infection of S. mutans caused dental caries marked by changes of the enamel teethcolour, turn to yellow and accompanied by the emergence of black dots.The TNF-α, TLR3, TLR4, IgA, IFN-γof parotid glands decreased, but the IL-10 increased significantly. Infection of S. mutans onto the enamel and between the teeth of mice caused dental caries and immunologically S. mutans suppress the mice immune system, both cellular and humoral, both innate and adaptive immunity.