IL6 and chronic periodontitis: The third study [31] found no significant difference in IL-6 level between the antibiotic group (SDD) and placebo group in 128 post-menopausal women with chronic periodontitis after two years (40% SDD versus 46% placebo; odds ratio [OR] 0.72, 95%CI: 0.30 to 1.69, p = 0.4).