Objective To explore the aesthetic effect of gingival retraction cord technique combined with resin filling in the treatment of senile tooth wedge-shaped defects. Methods A total of 60 elderly patients with tooth wedge-shaped defects admitted to the Department of Stomatology, Hedong District Xiangyanglou Street Community Health Service Center from March 2023 to March 2024 were selected, and they were divided into the control group and the observation group by the random number table method, with 30 patients in each group. The control group was treated with conventional resin filling restoration, and the observation group was treated with gingival retraction cord technique combined with resin filling restoration. The aesthetic effect, restoration appearance matching and adaptability, periodontal indexes, bleeding rate and satisfaction were compared between the two groups. Results The scores of color, shape and function in the observation group after treatment were higher than those in the control group (P <0.05). The scores of appearance matching and adaptability of the observation group after treatment were better than those of the control group (P <0.05). The GI and BI scores of the observation group after treatment were lower than those of the control group (P <0.05). The bleeding rate of the observation group was lower than that of the control group, and the satisfaction rate was higher than that of the control group (P <0.05). Conclusion The application of gingival retraction cord technique combined with resin filling in the treatment of senile tooth wedge-shaped defects has an ideal aesthetic effect. It can effectively improve the appearance matching and adaptability of the restoration, further optimize the periodontal indexes, help to reduce the postoperative bleeding rate and improve patient satisfaction.