A family–school–community–hospital closed-loop intervention for childhood caries management: a cluster-randomized controlled trial

Childhood dental caries remains common, and children identified through school screening may not subsequently receive dental care. This study evaluated a digitally enabled family–school–community–hospital (FSCH) intervention designed to link school-based screening with referral, follow-up, and family support. This cluster-randomized controlled trial was conducted in four primary schools in Shanghai, China. Schools were randomized before participant recruitment. Of 610 children assessed for eligibility, 576 were enrolled and 528 were included in the complete-case analysis at 12 months. Children in the intervention group received routine school screening together with structured referral, community follow-up, appointment support, verification of dental attendance and treatment, feedback to schools and families, oral health education, and WeChat-supported home-care supervision. The control group received routine school-based screening. The primary outcome was dental service utilization during the 12-month follow-up. Secondary outcomes included oral health behaviors, dietary habits, clinical indicators, and parental oral health knowledge and attitudes. Outcomes were analyzed using generalized linear or linear mixed-effects models with school included as a random intercept. Dental service utilization increased from 61.7% to 90.2% in the intervention group, compared with a decrease from 63.3% to 59.8% in the control group. The group × time interaction was significant ( OR = 6.39; 95% CI : 3.55–11.52; P < 0.001). Effects on secondary outcomes were less consistent. Significant group × time interactions were observed for five of eight oral health behaviors and two of five dietary indicators. The intervention group also showed a greater reduction in decayed-teeth count ( β = -1.40; 95% CI : -1.72 to -1.08; P < 0.001) and a greater increase in filled-teeth count ( β = 1.14; 95% CI : 0.76–1.53; P < 0.001), whereas the group × time interaction was not significant for the combined caries-experience count. Parental oral health knowledge and attitudes improved, with a significant interaction for the total score ( β = 3.56; 95% CI : 3.17–3.95; P < 0.001). The FSCH intervention was associated with substantially greater dental service utilization over 12 months, together with improvements in selected behavioral, parental, and clinical outcomes. The reduction in decayed teeth accompanied by an increase in filled teeth, without a significant change in the combined caries-experience count, suggests improved management of existing caries rather than prevention of new disease. Chinese Clinical Trial Registry, ChiCTR2600116048 registered January 5, 2026. Retrospectively registered.