IL1B and periodontitis: An analysis of IL-1A−889 and IL-1B+3953 genotype frequencies revealed that the IL-1B+3953 C/T genotype was significantly more frequent in the group with periodontitis (p = 0.016), whereas the prevalence of the IL-1B+3953 C/C genotype was significantly lower (p = 0.029) (Figure 3).