Background and Objective: Vitamin D-binding protein (DBP) is a multifunctional and highly expressed plasma protein. Among its diverse roles, including those in the immune and inflammatory responses, it is the primary carrier of vitamin D,which has been implicated in periodontitis. We hypothesized that there is a correlation between systemic DBP levels and generalized aggressive periodontitis (GAgP).

Material and Methods: Forty-four patients with GAgP and 32 healthy controls were recruited. Clinical parameters were examined, including the mean bleeding index, probing depth, attachment loss and percentage of severely affected sites.Blood chemistry analyses were performed for each subject. Plasma levels of DBP,interleukin-6 (IL-6) and procalcitonin (PCT) were measured using ELISAs, and plasma levels of 25-hydroxy-vitamin D3 (25(OH)D3) were detected using aradioimmunoassay.

Results:Significantly higher levels of plasma DBP, IL-6, PCT and 25(OH)D3,as well as leukocyte counts, neutrophil counts and neutrophil percentages were found in patients with GAgP compared with healthy controls ( p < 0.05 for all). Multiple linear regression analysis showed that the plasma DBP levels were significantly correlated with GAgP, plasma PCT levels and smoking status ( p < 0.05 for all).In the GAgP group, the plasma DBP levels in smokers were significantly higherthan those in nonsmokers ( p < 0.001).

Conclusion: Elevated plasma vitamin DBP levels are associated with GAgP.