Incipient periodontitis and salivary molecules among Korean adults: association and screening ability.

AIM: This study aims to evaluate the association of salivary matrix metalloproteinase-9 (MMP-9) and interleukin-8 (IL-8) with periodontitis and its screening ability on periodontitis. MATERIAL AND METHODS: We selected 693 participants from the Yanypyeong Cohort: 577 participants with periodontitis and 116 participants without periodontitis. Periodontitis was assessed by dentists using a panoramic radiograph. Salivary MMP-9 and IL-8 were assayed using multiplexed bead immunoassay (Luminex). MMP-9 and IL-8 were categorized into low, medium and high. Age, sex, income, smoking, drinking, exercise, obesity and metabolic syndrome were confounders. Logistic regression analysis was applied to evaluate the association between MMP-9, IL-8 and periodontitis. Receiver operating characteristic curve was applied for sensitivity, specificity and c-statistics. RESULTS: High MMP-9 and medium IL-8 were associated with periodontitis: adjusted odds ratio were 2.2 [95% confidence interval (CI): 1.3-3.7] for MMP-9 and 1.9 (95% CI: 1.1-3.4) for IL-8. The final screening model using salivary MMP-9 for periodontitis had a sensitivity of 0.46, specificity of 0.77 and c-statistic of 0.63 (p < 0.001). CONCLUSIONS: Our data show that salivary MMP-9 and IL-8 could be potential markers for periodontitis. The screening model for periodontitis could be useful in clinics and home. A future prospective study is indicated for predicting the occurrence of periodontitis.