Recent studies [1, 2, 7] have shown that raised salivary levels of inflammatory proteins including matrix metalloproteinases-9 (MMP-9), tumor necrosis factor-alpha (TNF-α) and nod-like receptor family pyrin domain-containing protein-3 (NLRP3) complex inflammasome contribute towards the occurrence of periodontitis. Here, MMP9 is linked to periodontitis.