Estimation of midkine levels in serum and gingival crevicular fluid in smokers and non-smokers of chronic gingivitis patients – A clinico-biochemical study.

Objectives: To detect the presence of Midkine in serum and gingival crevicular fluid (GCF) of healthy non-smokers, chronic gingivitis smokers, and non-smoker individuals and to evaluate the role of Midkine in the progression of gingival inflammation. Materials and Methods: Periodontal clinical parameters examination including gingival index, pocket probing depth, clinical attachment level, and collection of GCF and serum was performed on 60 subjects, categorized into three groups with 20 subjects in each group: Group I (healthy non-smokers); Group II (chronic gingivitis non-smokers), and Group III (chronic gingivitis smokers). GCF and serum were collected from 20 patients of each group. Midkine levels were estimated using the enzyme-linked immunosorbent assay. Results: Midkine was detected in all samples. The results of this study suggest that mean GCF and serum Midkine levels were the highest in Group III and varied significantly from those of Groups I and II. Furthermore, GCF and serum Midkine levels increased proportionally with the progression of inflammation. Conclusion: As the gingival disease progresses, there is a substantial increase of Midkine concentrations in serum and GCF. Since, Midkine levels in the GCF and serum correlated positively with clinical parameters, Midkine may be considered as a "novel biomarker" in disease progression. However, controlled longitudinal studies are required to confirm this possibility. [ABSTRACT FROM AUTHOR]