Objective To analyze the effect of polishing with silicon points on marginal sealing in patients with dental caries after composite resin fflling of carious cavities. Methods A total of 86 patients with dental caries admitted to the Department of Stomatology, Nanjing Lishui District Hospital of Traditional Chinese Medicine from January 2024 to June 2025 were selected as the research subjects. According to the random number table method, they were divided into the control group and the observation group, with 43 patients in each group. The control group received composite resin fflling of carious cavities, and the observation group received polishing with silicon points after composite resin filling of carious cavities. The restoration effect, marginal sealing, inffammatory factor indexes and complication rate were compared between the two groups. Results The total effective rate of the observation group (97.67%) was higher than that of the control group (81.40%) (P<0.05). After treatment, the scores of all indexes related to marginal sealing in the observation group were higher than those in the control group (P<0.05). The levels of all inffammatory factor indexes in the observation group were lower than those in the control group after treatment (P<0.05). The incidence of complications in the observation group (4.65%) was lower than that in the control group (23.26%) (P<0.05). Conclusion The application of polishing with silicon points during composite resin filling of carious cavities can improve the treatment effect. This operation can not only enhance the marginal sealing of the filling, reduce the risk of postoperative complications, but also help to decrease the levels of local inffammatory factors and promote tissue recovery.