The purpose of this study was to evaluate the skeletodental change by conventional comprehensive edgewise appliances in Class II treatments. Nonextraction group(22) and fast premolar extraction group(20) were examined in this study. Various measurements in pre-treatment and post-treatment lateral cephalograms were evaluated by superimposing the cephalograms in reference to the cranial base, the palatal plane or mandibular plane, respectively.
The results were as follows;
1. Both nonextraction group and extraction group showed the significant increase in Condylion-A point and mandibular body length.
2. Both nonextraction group and extraction group showed the significant increase in vertical dimension, such as anterior facial height, posterior facial height and lower facial height, and the significant steepening of the occlusal plane.
3. In nonextraction group, maxillary incisors were retracted and extruded. Maxillary molars were extruded and mandibular molars were uprighted, with no mesial movement.
4. In extraction group, both maxillary and mandibular incisors were retracted and extruded. And, maxillary molars were extruded and moved mesially, and mandibular molars were extruded and moved mesially, with no menial tilting.
|