Objective To explore the effect of resin cement on tooth aesthetics and sensitivity in patients with tooth defect. Methods A total of 70 patients with tooth defect admitted to our hospital from January 2020 to December 2022 were selected as the research subjects. They were divided into control group (n =34) and observation group (n =36) according to different treatment methods. The control group was treated with glass ionomer cement, and the observation group was treated with resin cement. The tooth aesthetics, sensitivity, repair effect, gingival sulcus inflammatory factors, complication rate and satisfaction were compared between the two groups. Results After treatment, the tooth aesthetics score in the observation group was higher than that in the control group, and the sensitivity score was lower than that in the control group (P <0.05). The total effective rate of repair in the observation group was 94.44%, which was higher than 73.53% in the control group (P <0.05). The levels of CRP, IL-6 and TNF-α in the observation group after repair were all lower than those in the control group (P <0.05). The incidence of complications in the observation group was 2.78%, which was lower than 20.59% in the control group (P <0.05). The satisfaction rate in the observation group was 94.44%, which was higher than 70.59% in the control group (P <0.05). Conclusion The application of resin cement repair in patients with tooth defect can effectively improve tooth aesthetics, reduce tooth sensitivity, achieve an ideal repair effect, reduce the inflammatory response of gingival sulcus, and the incidence of complications after repair is low, which is conducive to improving patient satisfaction.