Several studies (for example Lee et al. [6], Romanelli et al. [7], Kiili et al. [8], Sorsa et al. [9], and Alassiri et al. [10]) have demonstrated how elevated levels of active matrix metalloproteinase-8 (aMMP-8), but not total or latent MMP-8, differentiate periodontitis from gingivitis, and precede periodontal attachment loss. Here, MMP8 is linked to periodontitis.