Objective To analyze the effect of bracketless invisible appliance on enamel demineralization in patients with orthodontics. Methods The clinical data of 48 patients with orthodontics admitted to Beijing No.6 Hospital from June 2022 to June 2024 were retrospectively analyzed. According to different treatment plans, they were divided into the control group and the observation group, with 24 patients in each group. The control group was treated with straight wire appliance with metal brackets, and the observation group was treated with bracketless invisible appliance. The enamel demineralization, clinical efficacy, pain degree and periodontal indexes were compared between the two groups. Results The incidence of enamel demineralization in the observation group (8.33%) was lower than that in the control group (33.33%) (P <0.05). The total effective rate of treatment in the observation group (95.83%) was higher than that in the control group (75.00%) (P <0.05). The VAS scores in the observation group at 6, 24 and 48 hours after wearing were lower than those in the control group (P <0.05). The PLI and SBI in the observation group after treatment were lower than those in the control group (P <0.05). Conclusion The application of bracketless invisible appliance in patients with orthodontics has a good effect. It can effectively reduce the incidence of enamel demineralization, and is beneficial to reducing the pain degree, improving periodontal indexes and maintaining oral health.