ObjectiveConsidering the rising prevalence of metabolic syndrome (MetS), this study aimed to investigate the relationship between MetS and its components with oral and dental health in the adult population of the Azar cohort.MethodsIn this cross-sectional study oral health care behaviors, DMFT (decayed, missing, and filled teeth) index, and demographic data related to 15,006 patients (5112 in the MetS group and 9894 in the healthy group) of the Azar Cohort population aging from 35 to 70 were collected using appropriate questionnaires. The definition of MetS was based on the National Cholesterol Education Program Adult Treatment Panel III (ATP III) criteria. Then, the risk factors of MetS related to oral health behaviors were determined by proper statistical analysis.ResultsThe majority of MetS patients were female (66%) and uneducated (23%) (P < 0.001). In the MetS group, the DMFT index (22.15 ± 8.89) was significantly (p< 0.001) higher (20.81 ± 8.94) than the no MetS group. Not brushing at all was associated with increased odds of MetS (unadjusted OR = 1.12, adjusted OR = 1.18). Flossing less than once a day was associated with increased odds of abdominal obesity (unadjusted OR = 1.17, 95%CI = 1.03–1.32) and hyperglycemia (unadjusted OR = 1.88, 95%CI = 1.61–2.20).ConclusionsThis study showed that in MetS patients of the Azar cohort study, oral hygiene was worse compared to that in the no MetS group. Further studies are suggested to encourage oral hygiene among the general population which has more beneficiary effects than has been known before.