Circulating undercarboxylated osteocalcin and gingival crevicular fluid tumour necrosis factor-α in children.

ABSTRACT

BACKGROUND: Osteocalcin, a protein secreted by osteoblasts during bone formation, is negatively associated with adult periodontal disease. Little is known about this association in children. AIM: To examine the extent to which plasma undercarboxylated osteocalcin (ucOC) is associated with gingival crevicular fluid tumour necrosis factor-alpha (GCF TNF-α) - a potential marker of gingival inflammation - in children. METHODS: We used data from the Quebec Adipose and Lifestyle InvesTigation in Youth cohort, an ongoing longitudinal study on the natural history of obesity among Caucasian children with a family history of obesity in Quebec, Canada. This cross-sectional analysis from the baseline visit includes 120 children aged 8-10 years. Plasma ucOC and GCF TNF-α levels were determined by enzyme-linked immunosorbent assay. Linear regression analyses, adjusting for age, gender, family income, sexual maturity stage, daily physical activity, obesity, and fasting glucose were conducted, with TNF-α level as the dependent variable. RESULTS: A 1-ng/ml increase in ucOC was associated with a 0.96% decrease (95% confidence interval (CI) -1.69, -0.23) in GCF TNF-α level. CONCLUSION: A negative association between a marker of bone formation and a marker of gingival inflammation was observed as early as childhood among Caucasian children with a family history of obesity.