Relationship between smoking status and periodontal conditions: findings from national databases in Japan

BACKGROUND AND OBJECTIVE: The association between cigarette smoking and periodontitis was examined employing two nationally representative samples of adults in Japan. MATERIAL AND METHODS: Data were derived from the Survey of Dental Diseases (SDD) and the National Nutrition Survey (NNS) in 1999. In the SDD, periodontal conditions were evaluated by calibrated dentists utilizing the Community Periodontal Index (CPI), whereas in the NNS, participants were interviewed on the basis of smoking status by enumerators. Among 6805 records electronically linked via a household identification code, 4828 records of individuals aged 20 yr or older were analyzed. RESULTS: The prevalence of periodontal disease varied significantly by smoking status (p < 0.0001): 39.3%, 49.5% and 47.3% (CPI > or = 3), and 7.9%, 11.7% and 12.4% (a more severe form of periodontitis, CPI = 4), for nonsmokers, former smokers and current smokers, respectively. In adults aged > or = 40 yr (n = 3493), logistic regression models revealed greater probabilities (approximately 1.4 times higher) of periodontitis [CPI > or = 3, odds ratio = 1.38 (1.12-1.71), p = 0.0024] and a more severe form of periodontitis [odds ratio = 1.40 (1.04-1.89), p = 0.0288] in current smokers compared with nonsmokers, following adjustment for possible confounding factors. CONCLUSION: Based on the findings of this study and other numerous reports, cigarette smoking leads to deterioration of periodontal conditions in Japanese adults.