Plaque mediated cytokine degradation is a potential mechanism to explain the reduced levels of pro-inflammatory cytokines (IL-6) and chemokines (IL-8) found in the GCF of patients with periodontitis [31-35], as well as the GCF from sites with active periodontal disease or unresolved defects following treatment [33,36]. This evidence concerns the gene IL6 and periodontal disorder.