The Clinical effectiveness of sequential treatment of skeletal class III malocclusion among patients with maxillary retrognathism at Jilin University Stomatological Hospital, China

Abstract

Aim: To assess the dentofacial changes induced by the sequential treatment in the skeletal class III malocclusion with maxillary retrognathism. Study design: Controlled clinical trial assessing the effectiveness of sequential treatment of skeletal class III malocclusion. Materials and Methods: The treated group consisted of 30 patients in pre or during pubertal growth with anterior crossbite, maxillary crowding and class III molar relationship treated with maxillary protraction therapy; Pendulum appliances to distalize molars followed by fixed appliances. The treated group was compared with a control group of 10 untreated Class III subjects. Cephalometric analysis and Paired sample t test and Independent sample t test were used to evaluate the changes and treatment effects. The significance level was set at p ≤ 0.05. Results: After the sequential treatment, the maxilla moved forward, the mandible rotated clockwise leading to improved maxillomandibular sagittal relationship. The upper incisors moved forward, the anteroposterior relationship improved, and the class III concave profile turned to straight. The cephalometric variables; SNA, MP/SN and U1/SN showed significant changes at p ≤ 0.001, p≤ 0.01 and p≤ 0.01 respectively. Conclusion: The sequential treatment approach is effective for skeletal class III malocclusion with maxillary retrognathism for low and average mandible angle young patients.