ABSTRACT
Objective:This study was aimed to explore the associations between the risk of dental fluorosis and the serum biomarkers of bone metabolism in children.Methods:A total of 502 children aged 7 - 12 years were selected by cluster sampling from 4 primary schools in Tongxu County, Kaifeng City, Henan Province from April to May 2017. Morning urine and fasting peripheral blood samples were collected from each participant. Urinary fluoride concentration was determined by fluoride ion selective electrode method. Serum calcium, phosphorus, alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP), osteocalcin (OC), calcitonin (CT) and parathyroid hormone (PTH) levels were measured using an automatic biochemical analyzer. Dean method was used to evaluate the prevalence of dental fluorosis in children, and the participants were divided into dental fluorosis group ( n = 173) and control group ( n = 329) after being diagnosed by trained physicians for their dental fluorosis. The associations between the risk of dental fluorosis and the serum biomarkers of bone metabolism in children were analyzed by logistic regression. Results:The levels of serum phosphorus (mmol/L: 1.54 ± 0.19 vs 1.58 ± 0.21) and OC (ng/ml: 11.59 ± 5.22 vs 12.78 ± 5.88) in children in dental fluorosis group were significantly lower than those in children in control group ( P < 0.05). Logistic regression analysis showed that serum OC level affected the risk of dental fluorosis [odds ratio ( OR) = 0.96, 95% confidence interval ( CI): 0.92 - 0.99, P < 0.05]. The relative contribution of the biomarkers of bone metabolism to the risk of dental fluorosis in descending order were serum OC (36.34%), phosphorus (25.89%), BALP (13.16%), PTH (9.73%), calcium (9.44%), CT (3.72%) and ALP (1.72%). Conclusions:The prevalence of dental fluorosis in children is related to the changes of serum biomarkers of bone metabolism. Serum OC plays an important role in the occurrence of dental fluorosis.