Associations of interleukin (IL)-1β, IL-1 receptor antagonist, and IL-10 with dental caries

Streptococcus mutans is important in dental caries. Although the role of cytokines in the pathogenesis of dental caries is not clear, components of S. mutans were found to stimulate production of pro-inflammatory cytokines. We examined the associations of interleukin (IL)-1β, IL-1 receptor antagonist (IL-1ra), and IL-10 with dental caries. Unstimulated whole saliva and blood samples were obtained from 108 children aged 6-12 years with high caries (decayed, missing, or filled teeth [dmft/DMFT] index >4, n = 37), moderate caries (dmft/DMFT = 1-4, n = 37), or caries-free (dmft/DMFT = 0, n = 34). S. mutans level was classified as low (<10(5) colony-forming units [CFU]/mL) or high (≥10(5) CFU/mL). Saliva and serum concentrations of IL-1β, IL-1ra, and IL-10 were determined by ELISA. IL-1β, IL-1ra, and IL-10 gene polymorphisms were genotyped using PCR and restriction fragment length polymorphism analysis. The chi-square, Mann-Whitney U, one-way ANOVA, posthoc, Fisher's exact, and t tests were used in statistical analysis. Dental caries was not correlated with salivary or serum concentrations of the studied cytokines. S. mutans level positively correlated with saliva IL-1β concentration and inversely correlated with saliva IL-1ra concentration. There was no correlation of IL-1β, IL-1ra, or IL-10 gene polymorphisms with dental caries. S. mutans is important in stimulating saliva IL-1β and inhibiting IL-1ra. Future studies of associations between cytokines and dental caries should investigate additional cytokines and enroll a larger number of participants.