ABSTRACT We investigated the association between ambient air pollutant exposure and periodontal health using data from 17,271 adults in the Korea National Health and Nutrition Examination Survey (2012–2015). Participants’ periodontal status was categorized based on their community periodontal index (CPI) scores. Using multiple logistic regression models, we examined the relationship between air pollutant levels and poor periodontal status at various lag periods. After adjusting for potential confounders, PM10 exposure was associated with a poor periodontal status (short-term: 0–1 and 0–2 lag days; medium-term: 0–1 and 0–2 lag months). SO2 exposure showed similar associations (short-term, 0–2 to 0–7 lag days; medium-term, 0–4 to 0–6 lag months). Only increased medium-term O3 exposure (0–2 to 0–6 lag months) was associated with a poor periodontal status. NO2 exposure was inversely associated with poor periodontal status for both short- and medium-term durations.