CLINICAL-RESULTS OF THE MAXILLARY PROTRACTION IN KOREAN CHILDREN

Sixty subjects with ages ranging from 8 to 13 years were divided into two groups according to the intraoral appliances used. Group I consist ed of 47 subjects with rapid palatal expansion (RPE) appliances End gr oup II consisted of 13 subjects with labiolingual appliances (La/Li). Group I was subdivided into three subgroups by age and two subgroups b y the timing of the protraction. The cephalometric radiographs of all subjects were analyzed before and after correction of anterior crossbi te. The following results were obtained: (1) After maxillary protracti on, the maxilla and maxillary dentitions moved forward and downward, a nd the mandible and mandibular dentitions moved backward and downward. (2) The maxilla moved more forward in the RPE group, compared with La /Li group. (3) The palatal plane angle decreased more in the protracti on-during-palatal expansion group than protraction-after-palatal-expan sion group. (4) Age did not show any statistically significant differe nce.