Associations of duration of smoking cessation and cumulative smoking exposure with periodontitis.

This cross-sectional study investigated associations of cumulative smoking exposure and duration of smoking cessation with periodontitis and evaluated the effects of biological, behavioral, and social risk variables on these associations. The sample comprised 705 adults of both sexes (age, 35-65 years) who underwent a full-mouth periodontal examination. Subjects were classified according to smoking status as nonsmokers, former smokers, and current smokers, and univariate and multivariate analysis was used to evaluate associations between periodontitis prevalence and potential risk variables. The rates of periodontitis among nonsmokers, former smokers, and current smokers were 25.6%, 29.3%, and 45.1% respectively. After adjusting for other periodontal risk variables the odds ratio (95% confidence interval) for periodontitis was 3.09 (1.98-4.92) for former smokers and 5.24 (2.61-8.97) for current smokers. A significant dose-response relationship between pack-years of smoking and periodontitis prevalence was observed, as was a significant decrease in the risk of periodontitis as years of smoking cessation increased. Cumulative smoking exposure and duration of smoking cessation were significantly associated with periodontitis.