This study aimed to investigate the new development of caries among preschoolers in northern Guangdong and to assess caries-related factors to distinguish groups with different caries risk levels. Methods: Baseline data were recorded for participants from September to November 2019, and participants were reexamined from September to November 2020. A longitudinal observation of 11,973 preschoolers was conducted. The simplified debris index (DI-S) and decayed-missing-filled tooth (dmft) index values were obtained for each participant. Results: Factors associated with whether caries would occur in the future and one-year increase in dmft (Δdmft) included baseline dmft, baseline DI-S, and baseline age. The risk ratio (RR) of caries occurrence and the number of teeth with new-onset caries were 4.482 (95% confidence interval, 4.056-4.957) and 2.945 (2.742-3.165) in the participants with baseline dmft ≥3, which were higher than those with baseline dmft =1 or 2. In the baseline caries-free group, whether caries would occur in the future was related to the baseline DI-S (95% confidence interval, 0.022-0.062). The caries incidence of maxillary central incisors (27.9%) was the highest among teeth of preschoolers without caries at baseline, whereas the caries incidence of mandibular first deciduous molars (42.7%) was the highest among teeth of preschoolers with caries at baseline. Conclusion: Baseline dmft is a good predictor of future caries. Children with baseline caries-free status, baseline dmft >0, and baseline dmft ≥3 should be treated with preventive interventions of different intensities and frequencies. The occurrence of future caries in baseline caries-free participants is related to oral hygiene status. Measures to prevent caries on smooth surfaces, such as topical fluoridation, should be applied to all preschoolers. Preschoolers with caries at baseline may be given priority for pit and fissure sealing.

PurposeTo construct an online caries management platform and evaluate its efficacy in children's caries prevention based on caries risk.MethodsThe study participants were second-grade pupils. The caries risk assessment tool (CAT) was used to grade caries risk for all participants, who were randomly divided into the experimental (114 pupils) and control (111 pupils) groups. The experimental group used the Internet for caries management, while the control group was managed by traditional lecturing in classroom. The caries status of each surface of the first permanent molars was recorded. The basic information and oral health knowledge, attitude, and behaviors of participants were collected by questionnaire. One year later, outcome data were collected. Pearson's chi-squared test was used to analyze the caries risk assessment items and oral health behaviors. The Mann-Whitney U-test was used to analyze the decayed-missing-filled surfaces (DMFS) index, plaque index, and scores of oral health knowledge and attitude. P < 0.05 was considered statistically significant. This study was available on the website of Chinese Clinical Trials Register (No: MR-44-22-012947).ResultsAfter 1 year, the oral health knowledge score was improved by 20.58% (P < 0.001) in the experimental group and 6.02% in the control group. The plaque index was improved by 49.60% (P < 0.001) in the experimental group and 21.01% in the control group. The DMFS index increased in both groups but there were no significant differences (P = 0.608). The experimental group had a better improvement effect in caries risk assessment items than the control group, including “whether the frequency of eating sugary snacks or drinks between meals is more than 3 times/day” (P = 0.033) and the use of fluoridated toothpaste (P = 0.020). The experimental group was better than the control group in reported oral health behaviors, including frequency of eating sweets before sleep (P = 0.032), brushing time (P = 0.001), and the filled rate (proportion of FS in DMFS) of first permanent molars (P = 0.003).ConclusionsThe online caries management platform showed more advantages than traditional lecturing in improving oral health knowledge and behaviors (oral hygiene practice, sugar consumption behavior, and medical treatment behavior). This platform provides a reliable implementation path for the occurrence and continuous improvement of oral health-related behaviors.