Clinical application of lower second molar extraction to correction of skeletal Class III malocclusion

Objective To study the clinical application of lower second molars extraction and treatment using MEAW in non-surgical patients with skeletal Class Ⅲ malocclusion. Methods Seven non-surgical patients of skeletal Class Ⅲ malocculsion( male 3,female 4,age ranging 13 ～16 years old,mean age 14.3)were included in the study. They were treated by MEAW technique after extraction of lower second molars;cephalometric films at the beginning and end of treatment were analyzed using cephalometric analysis. Results After treatment,all the patients reached normal occlusion relationship,the cross bite of anterior tooth was corrected,and reached the normal overbite and overjet. The lower first molars was moved 3.1 mm posteriorly ,the lower incisors were moved 2.8 mm lingually,and the angle of ANB were increased 1.2 degree. The difference was of statistical significance. Conclusions The treatment of MEAW technique after extraction of lower second molars is suitable for the non-surgical patients of skeletal Class Ⅲ malocclusion in the period of permanent teeth,whose dental germs of lower third molar are normal,and whose dentition is crowded in the mandible,and has a tendency of openbite.