Abstract
Morphological features of the craniofacial complex during orthopedic chin cup therapy were investigated in growing patients with mandibular prognathism. Lateral cephalograms of 30 subjects (15 boys and 15 girls, mean age: 9.04 ± 1.29 years), taken at four different stages during treatment, were analyzed for 14 measurements. These measured values were standardized by use of Japanese controls and then evaluated to investigate longitudinal changes in the craniofacial morphology at the four different stages. Further, factor analysis was used to compare factors describing the craniofacial morphology for the initial and final stages. Dimensional changes of the mandible were not easily produced even if orthopedic treatment was conducted, whereas the maxilla exhibited a tendency to approach the normal range of the controls. Positional changes of the complex, the backward and downward repositioning of the mandible in particular, played an important role in altering a profile from prognathic before treatment to orthognathic at the end of treatment. Craniofacial morphology was similar pretreatment and posttreatment, although the orthognathic factor became more prominent when associated with positional changes of the mandible at the end of treatment.
Author notes
Dr. Lu is Graduate Student in the Graduate Institute of Dental Sciences, Kaohsiung Medical College
Dr. Hirano is Clinical Associate in Osaka Medical Center and Research Institute for Maternal and Child Health
Dr. Tanne is Professor and Chairman, Department of Orthodontics, Hiroshima University School of Dentistry
Dr. Sakuda is Professor and Chairman of the Department of Orthodontics, Osaka University Faculty of Dentistry