Objective To analyze the effect of super-ceramic resin inlay restoration on restoration effect and periodontal indicators in patients with large-area molar defect. Methods A total of 72 patients with large-area molar defect admitted to Nanjing Xuanwu Dental Hospital from December 2024 to May 2025 were selected, and they were divided into the control group and the observation group by the random number table method, with 36 patients in each group. The control group was treated with composite resin filling restoration, and the observation group was treated with super-ceramic resin inlay restoration. The restoration effect, periodontal indicators, masticatory function and adverse reaction rate were compared between the two groups. Results The restoration success rate of the observation group (97.22%) was higher than that of the control group (50.00%) (P <0.05). The PLI score and PPD of the observation group after treatment were better than those of the control group (P <0.05). The scores of clinical examination, drinking water test and normal eating in the observation group after treatment were lower than those in the control group (P <0.05). The incidence of adverse reactions in the observation group (2.78%) was lower than that in the control group (50.00%) (P <0.05). Conclusion Super-ceramic resin inlay restoration has an ideal restoration effect in patients with large-area molar defect. It can effectively improve periodontal indicators and masticatory function, and reduce the incidence of adverse reactions.