title: Severe Class II Division 1 malocclusion in an adolescent patient, treated with a novel sagittal-guidance Twin-block appliance.
abstract: Class II malocclusion is a challenging anomaly in orthodontic practice. Various types of functional appliances are used to correct Class II skeletal and occlusal disharmonies in growing patients, including the Twin-block. We used a modified sagittal-guidance Twin-block appliance combined with a fixed appliance and microimplant anchorage to treat a 13-year-old Chinese boy with a severe skeletal Class II malocclusion and mandibular retrognathia. Normal overjet and a Class I molar relationship were achieved because of the advancement of mandibular development, the restriction of maxillary growth, and dentoalveolar modifications in both the maxilla and the mandible. Favorable skeletal, dental, and soft tissue relationships were accomplished after 24 months of treatment. After 2 years of retention, the results remained stable.
authors.affiliation: Postgraduate student, Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Peilun
authors.initials: P
authors.lastname: Li
authors.affiliation: Assistant professor, Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department chair, Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Shen
authors.affiliation: Assistant professor, Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, Shanghai, China. Electronic address: zhaon1995@126.com.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000628:therapy*; D017289:Orthodontic Appliances, Functional; D012720:Severity of Illness Index