Objective To investigate the effect of all-ceramic onlay restoration on periodontal indicators and aesthetic effect in patients with anterior tooth defect. Methods A total of 88 patients with anterior tooth defect admitted to Liuwei Hospital of Liuzhou from January 2023 to April 2025 were selected as the research subjects. According to the random number table method, they were divided into the reference group and the experimental group, with 44 patients in each group. The reference group received all-ceramic crown restoration, and the experimental group received all-ceramic onlay restoration. The periodontal indicators, aesthetic effect, restoration effect, satisfaction and complication rate were compared between the two groups. Results At 6 months after treatment, the scores of gingival index and bleeding on probing index in the experimental group were lower than those in the reference group (P<0.05). At 6 months after treatment, the scores of all aesthetic effect indicators in the experimental group were higher than those in the reference group (P<0.05). The excellent and good rate of restoration in the experimental group (97.73%) was higher than that in the reference group (84.09%) (P<0.05). The restoration satisfaction in the experimental group (97.73%) was higher than that in the reference group (84.09%) (P<0.05). The incidence of complications in the experimental group (4.55%) was lower than that in the reference group (20.45%) (P<0.05). Conclusion All-ceramic onlay restoration for patients with anterior tooth defect can effectively improve periodontal indicators, enhance aesthetic restoration effect, elevate restoration efffcacy and satisfaction, and reduce the risk of complications.