title: Severe skeletal Class III malocclusion treated with 2-stage orthognathic surgery with a mandibular step osteotomy.
abstract: To reduce a large amount of mandibular setback and to prevent pharyngeal airway space narrowing when correcting a severe anteroposterior skeletal discrepancy, a mandibular step osteotomy is often combined with 2-stage orthognathic surgery. This case report describes a successful 2-stage orthognathic treatment combined with a mandibular step osteotomy. A 20-year-old man had severe mandibular protrusion, facial asymmetry, and macroglossia. Phase 1 surgery included the mandibular step osteotomy and a partial glossectomy; then we performed phase 2 surgery with a 2-piece LeFort I segmental osteotomy and a bilateral intraoral vertical ramus osteotomy to correct the patient's mandibular protrusion and facial asymmetry. The total treatment period was 30 months, and the final result was improvement of the patient's facial appearance.
authors.affiliation: Postgraduate student, Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea.
authors.forename: Sung-Hwan
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Fellow, Department of Dentistry, Yongin Severance Hospital, Gyeonggi-do, Korea.
authors.forename: Da-Young
authors.initials: DY
authors.lastname: Kang
authors.affiliation: Resident, Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea.
authors.forename: Young-Hoon
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Professor, Department of Orthodontics, Institute of Craniofacial Deformity Center, College of Dentistry, Yonsei University, Seoul, Korea. Electronic address: hwang@yuhs.ac.
authors.forename: Chung-Ju
authors.initials: CJ
authors.lastname: Hwang
mesh_terms: D005927:Glossectomy / Q000379:methods; D006801:Humans; D008297:Male; D008313:Malocclusion, Angle Class III / Q000000981:diagnostic imaging / Q000601:surgery*; D063168:Mandibular Osteotomy / Q000379:methods*; D019340:Osteotomy, Le Fort / Q000379:methods*; D059229:Osteotomy, Sagittal Split Ramus / Q000379:methods*; D011859:Radiography; D055815:Young Adult