Influence of the consumption of sugary drinks and sleep duration on the association of Internet use and dental caries among 12–19 years old adolescents in Xiamen city, China

Background : This study investigated the prevalence of dental caries among adolescents aged 12–19 years in Xiamen, China and evaluated its association with Internet usage time. The mediation effect of sugary drinks consumption and sleep duration on the association between dental caries and Internet usage time was also examined. Methods : We recruited 11,361 adolescents using multistage stratified random sampling method in Xiamen. Dental caries assessment was conducted by professional dentists under natural light using disposable mouth mirrors and dental probes, following the World Health Organization (WHO) guidelines. Dental caries was evaluated with the sum of decayed, missing, and filled permanent teeth (DMFT) index. The information about demographic characteristics and lifestyle behaviors was collected by self-administered questionnaire. The association between Internet usage time and dental caries was analyzed using binary logistic regression. The mediation effect of sugary drinks consumption and sleep duration on the association was assessed using mediation analysis. Results : The overall prevalence of dental caries among adolescents aged 12–19 years in Xiamen was 56.9%, which varied among sex, age, residence, and body mass index (BMI) ( p < 0.001). Longer Internet usage time (adjusted odds ratios (AOR): 1.16; 95% confidence interval (95% CI): 1.02–1.32) was associated with a higher risk of dental caries. Moreover, higher sugary drinks consumption and insufficient sleep increased the risk of dental caries (sugary drinks: AOR: 1.54; 95% CI: 1.28–1.82; sleep duration: AOR: 1.23; 95% CI: 1.10–1.37). The frequency of sugary drinks consumption and sleep duration mediated the association between Internet usage time and dental caries by 13.89% and 5.56%, respectively. Conclusions : Adolescents aged 12–19 years-old in Xiamen had a high prevalence of dental caries, which was significantly associated with Internet usage time. The association between dental caries and Interne usage time was mediated by the frequency of sugary drink consumption and sleep duration.