BACKGROUNDRoot caries is a common oral disease among the elderly, and its prevalence increases year by year with the deepening of population aging. Existing caries risk assessment models do not fully consider the specific risk factors for root caries in the elderly population. This study aims to develop a predictive model for root caries risk in the elderly to facilitate early identification and personalized intervention.METHODSThis study included 310 individuals over the age of 60. Data on oral health status, frailty level, cognitive function, and sociodemographic factors were collected through oral examinations and six questionnaires, including the Fried Frailty Phenotype, MMSE, Barthel Index, SXI, OHIP-14, and a demographic questionnaire. A root caries prediction model was constructed using multivariate logistic regression analysis, and the model's performance was evaluated using the Hosmer-Lemeshow test, ROC curves, and Decision Curve Analysis (DCA).RESULTSKey risk factors for root caries included age, history of coronal caries, secondary caries, use of removable partial dentures, and the number of exposed root surfaces. The nomogram model demonstrated good predictive accuracy and clinical utility in both the training cohort (AUC=0.840) and the validation cohort (AUC=0.834).CONCLUSIONThe nomogram developed in this study provides an effective tool for the early assessment of root caries risk in the elderly. Future studies should conduct larger sample and multicenter validation research. The study was retrospectively registered in the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) with the registration number ChiCTR2500099297.CLINICAL SIGNIFICANCEThis nomogram prediction model can help clinicians identify high-risk elderly patients and take early preventive measures, enhancing personalized oral health management and improving the oral health of the elderly population.