Examples of such mechanisms include: causing a decrease in the effectiveness of the host's immune response, facilitating colonization by periodontal pathogenic bacteria, creating antibodies against neutrophils causing secondary infections,16or causing tissue damage and altering inflammatory mediators.12Both HSV, EBV and CMV cause latent infections, whose periodic reactivation aligns with the most common course pattern of periodontal disease.17CMV viruses and EBV lead to an increased expression of IL-1β (interleukin-1β) and TNFα (tissue necrosis factor) by macrophages and monocytes. This evidence concerns the gene TNF and periodontal disorder.