Components of adult class III malocclusion in an Iranian population

Background and aims. Class III malocclusions are considered complex and difficult orthodontic problems to diagnose and treat. The purpose of this study was to investigate the morphologic characteristics of the craniofacial complex of adults with Class III malocclusion in an Iranian population. Materials and methods. Lateral cephalometric radiographs of 50 patients with Class III malocclusion (20 males and 30 females; age range of 18-27 years) were selected on the basis of molar relationship, concave profile and an overjet of ≤ 0 mm. The standard values of 19 soft tissue measurements were determined using McNamara, Burstone and Viazis methods. Results. Adults with Class III malocclusion exhibited distinct craniofacial morphologic characteristics manifested by a combination of retrusion of maxilla and protrusion of mandible. Conclusion. The most prevalent component was mandibular prognathism, normal maxilla and LAFH on the basis of the component analysis.