Objective To explore the effect of straight wire appliance combined with functional appliance on periodontal health indexes, occlusion and masticatory function in adolescent patients with Angle class Ⅱ malocclusion. Methods A total of 40 adolescent patients with Angle class Ⅱ malocclusion admitted to Beihai People's Hospital from January 2022 to December 2024 were selected as the research subjects, and they were divided into the control group and the study group by the random number table method, with 20 patients in each group. The control group was treated with straight wire appliance technique, and the study group was treated with straight wire appliance combined with TB twin-block appliance. The periodontal health indexes, occlusion and masticatory function and bad oral habits improvement were compared between the two groups. Results After treatment, the GI, SBI and PLI in the study group were lower than those in the control group (P <0.05). The occlusion opening time in the study group was shorter than that in the control group, and the masticatory efficiency after treatment was higher than that in the control group (P <0.05). The total effective rate of bad oral habits improvement in the study group (95.00%) was higher than that in the control group (60.00%) (P <0.05). Conclusion The application of straight wire appliance combined with functional appliance in the treatment of Angle class Ⅱ malocclusion in adolescent patients can effectively correct their bad oral habits, promote occlusion recovery, improve periodontal health and masticatory function, which is worthy of clinical application.