There is only little evidence about the possible relationship between Metabolic Syndrome (MetS) and periodontitis. The contribution of systemic conditions and diseases in onset and exacerbation of periodontal disease is very well known. Because both periodontitis and metabolic syndrome are associated with systemic inflammation, these two diseases may be linked through common pathophysiological pathway. To prevent formation of metabolic syndrome, weight loss and physical activity is the initial step. In addition, to prevent inflammation, periodontal treatment is a high priority in patients with poor oral hygiene. More studies are needed to clarify possible link between metabolic syndrome and peri–implantitis which is inflammation of peri–implant mucosa and bone around dental implants.