Cephalometric evaluation of craniofacial pattern of Syrian children with Class III malocclusion.

摘要

The purpose of this study was to investigate the morphologic characteristics of the craniofacial complex of Syrian children with Class III malocclusion. Lateral cephalometric radiographs of 69 patients with Class III malocclusion (23 male and 46 female; ages 5 to 12 years) were selected on the basis of molar relationship. Cases were analyzed and compared with a Class I control group that was matched for age, sex, and ethnic origin. The children with Class III malocclusion exhibited a distinct craniofacial morphologic characteristic that was manifest in a combination of alterations in angular and linear measurements on the lateral cephalogram. Both the anterior cranial base (SN) and posterior cranial base (SAr) were significantly shorter than normal in the Class III group, and the cranial base angle (NSAr) was slightly smaller than normal. Maxillary length (Co-A) was significantly smaller, and the maxilla was more posteriorly positioned in the patients with Class III malocclusion. The mandible was within the neutral range of protrusion, and there was a slight increase in total mandibular length (Co-Gn), accompanied by a more forward positioning of the glenoid fossa in patients with Class III malocclusion. Dental aberrations in the patients with Class III malocclusion were manifested essentially by a significant decrease in the angulation and protrusion of the maxillary incisors relative to the A-Pog line, whereas the mandibular incisors showed only a slight amount of linguoversion. Patients with Class III malocclusion also tended to have a significantly smaller vertical face dimension and shorter lower anterior facial height (ANS-Me). Because of these distinct morphologic features, early orthopedic intervention with protraction face mask therapy may be the method of choice for most of the patients with Class III malocclusion included in this study.