Abstract: PURPOSE: To explore the effect of fluoride iontophoresis in preventing dental caries in children, characteristics of saliva fluoride metabolism and influencing factors. METHODS: A total of 500 children who underwent oral examinations from April 2022 to October 2023 were selected and divided into experimental group and control group according to the random number table method, with 250 children in each group. The control group received routine prevention, while the experimental group received fluoride iontophoresis prevention. The caries prevention effects, salivary fluoride concentrations and caries prevalence after 12 months of intervention were compared between the two groups before intervention and 12 months after intervention, according to whether they had caries or not, they were divided into caries group (n=258) and non-caries group (n=242). The general data of the two groups were compared, and the influencing factors of caries in children were analyzed by multivariate logistic regression. RESULTS: Twelve months after intervention, the decayed, missing and filled teeth (DMFT) index and significant caries index (SiC) in the experimental group were significantly lower than those in the control group (P<0.05). At 30 minutes, 2 hours, 4 hours, 6 hours, and 2 days after intervention, the salivary fluoride concentration in the experimental group was significantly higher than that in the control group (P<0.05). Twelve months after intervention, the caries incidence rate in the experimental group was significantly lower than that in the control group (P<0.05). The results of univariate analysis showed that age, weaning age, frequency of sweet food consumption, frequency of night eating, age of starting to brush teeth, brushing frequency, toothpaste with or without fluoride, regular check-ups and the concentration of free fluoride after intervention were the influencing factors of dental caries in children (P<0.05). The results of multivariate logistic regression analysis showed that older age and older weaning age were independent risk factors for dental caries in children (P<0.05), while the frequency of sweet food consumption<3 times per week, the frequency of nocturnal eating<5 times per week, fluoride content in toothpaste and regular oral examinations were independent protective factors for dental caries in children (P<0.05). CONCLUSIONS: Fluoride iontophoresis can significantly reduce the incidence of dental caries in children, increasing the fluoride concentration in saliva, affected by multiple factors.

Key words: Fluoride iontophoresis, Dental caries, Salivary fluoride concentration, Decayed, missing and filled teeth index, DMFT, Influencing factors