Surgical-orthodontic treatment in a skeletal class III patient. A case report

Resumen

A 24-year-old patient attended the Orthodontics Clinic of the Division of Postgraduate Studies and Research, Faculty of Dentistry, UNAM, with a previous orthodontic treatment and absence of lower 1st premolars. The chief complaint was an unattractive facial appearance due to a forward position of the mandible and anterior open bite. Upon facial examination, in the frontal view, a leptoprosopic face, collapsed paranasal areas and incompetent lips were observed. In the vertical facial proportions, the lower third was increased. The lateral and oblique view showed a greater projection of the chin, a concave profile and an increased mentocervical length. Intraorally, the molar relationship was class III; a 2
mm anterior open bite and complete anterior cross bite of 1 mm were also observed. The patient presented a mild discrepancy of the dental midline as well. Orthodontic treatment was carried out in three phases: presurgical, surgical and postsurgical. In the presurgical phase dental decompensation was performed and the patient was prepared for surgery. In the surgical phase a segmental maxillary surgery from lateral incisor to lateral incisor was performed
in order to produce a movement of sagittal rotation thus projecting the nasogenian area and improving incisor inclination. A mandibular setback via bilateral sagittal osteotomy was also performed. In the postsurgical phase ideal occlusal relationships were achieved in terms of canine class, molar class, overjet, overbite, centered dental midlines as well as a more harmonious profile.