Objective To investigate the effect of crown lengthening combined with glass fiber post repair in patients with residual root and crown of anterior teeth. Methods Sixty patients with residual roots and crown of anterior teeth admitted to the Department of Stomatology, Affiliated Hospital of Xiangnan University from January to December 2023 were selected as the research objects. They were randomly divided into control group (30 patients, 35 teeth) and observation group (30 patients, 36 teeth). The control group was treated with glass fiber post repair, and the observation group was treated with crown lengthening combined with glass fiber post repair. The repair success rate, aesthetic effect, chewing function and inflammatory factor levels were compared between the two groups. Results The success rate of repair in the observation group was 97.22%, which was higher than 82.86% in the control group (P<0.05). After treatment, the PES score and WES score of the two groups were higher than those before treatment, and those of the observation group were higher than those of the control group (P<0.05). The masticatory efficiency and bite force of the two groups after treatment were higher than those before treatment, and those of the observation group were higher than those of the control group (P<0.05). After treatment, PGE2, MMP2 and CAM1 in the two groups were lower than those before treatment, and those in the observation group were lower than those in the control group (P<0.05). Conclusion Crown lengthening combined with glass fiber post repair is effective in patients with residual roots and crown of anterior teeth, which can improve the success rate of repair and aesthetic effect, reduce the level of inflammatory factors, and improve the masticatory function and occlusal degree of patients.