Preliminary research of cranio-maxillo-facial hard tissue structure feature of skeletal class III malocclusion orthognathic patients with Delaire cephalometric analysis

Objective To analyze the cranio-maxillo-facial hard tissue structure feature with skeletal class Ⅲ malocclusion with Delaire cephalometric analysis,which will guide the orthodontic treatment before orthognathic surgery and the model surgery.Methods Lateral cephalometric radiographs of 33 patients with skeletal class Ⅲ occlusion(18-39 years old,ANB-4°) were evaluated with the same standard.The cranio-maxillo-facial hard tissue marks of each radiograph were measured with computer assistant Delaire cephalometric analysis.The data got from corresponding measure index were dealed with Tukey's test and ANOVA analysis through SAS9.0 statistical software.Results The cranio-maxillo-facial hard tissue structure feature of skeletal class Ⅲ could be divided into four classifications through Delaire cephalometric analysis including hypodivergent,hyperdivergent,maxilla normal and glenoid fossa retrocession.Eleven parameteres of four groups had significant variability through ANOVA analysis(P0.05).Conclusion The Delaire cephalometric analysis can identify growth feature of skeletal class Ⅲ malocclusion and formulate treatment planning for orthognathic surgery,which is very helpful to stability and harmony after the orthognathic surgery,so it is worth using and popularizing in clinic.