(i) medical history of cancer, rheumatoid arthritis, diabetes mellitus, or cardiovascular disease and any other systemic disease affecting lipid metabolism(i.e. impaired glucose tolerance, metabolic syndrome); (ii) compromised immune system; (iii) pregnancy, menopause, or lactation; (iv) ongoing drug therapy that might affect the clinical characteristics of periodontitis and lipid metabolism; (v) use of systemic antimicrobials during the 6 weeks prior to data collection; and (vi) dental treatment during the 6 months prior to data collection.