A key characteristic of active periodontal diseases is the pathological elevation and activation of MMP-8 to active MMP-8 (aMMP-8) in periodontal tissues, which are reflected in oral fluids (e.g., saliva, mouth rinse, gingival crevicular fluid, and peri-implant sulcular fluid) [6,7,8]. This evidence concerns the gene MMP8 and periodontal disorder.